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sciq-10409
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multiple_choice
|
What is it called when your joints start to wear out and they become stiff and painful?
|
[
"endometriosis",
"tendonitis",
"arthritis",
"adenitis"
] |
C
|
Relavent Documents:
Document 0:::
Arthritis of the knee is typically a particularly debilitating form of arthritis. The knee may become affected by almost any form of arthritis.
The word arthritis refers to inflammation of the joints. Types of arthritis include those related to wear and tear of cartilage, such as osteoarthritis, to those associated with inflammation resulting from an overactive immune system (such as rheumatoid arthritis).
Causes
It is not always certain why arthritis of the knee develops. The knee may become affected by almost any form of arthritis, including those related to mechanical damage of the structures of the knee (osteoarthritis, and post-traumatic arthritis), various autoimmune forms of arthritis (including; rheumatoid arthritis, juvenile arthritis, and SLE-related arthritis, psoriatic arthritis, and ankylosing spondylitis), arthritis due to infectious causes (including Lyme disease-related arthritis), gouty arthritis, or reactive arthritis.
Osteoarthritis of the knee
The knee is one of the joints most commonly affected by osteoarthritis. Cartilage in the knee may begin to break down after sustained stress, leaving the bones of the knee rubbing against each other and resulting in osteoarthritis. Nearly a third of US citizens are affected by osteoarthritis of the knee by age 70.
Obesity is a known and very significant risk factor for the development of osteoarthritis. Risk increases proportionally to body weight. Obesity contributes to OA development, not only by increasing the mechanical stress exerted upon the knees when standing, but also leads to increased production of compounds that may cause joint inflammation.
Parity is associated with an increased risk of knee OA and likelihood of knee replacement. The risk increases in proportion to the number of children the woman has birthed. This may be due to weight gain after pregnancy, or increased body weight and consequent joint stress during pregnancy.
Flat feet are a significant risk factor for the development
Document 1:::
Epicondylitis is the inflammation of an epicondyle or of adjacent tissues. Epicondyles are on the medial and lateral aspects of the elbow, consisting of the two bony prominences at the distal end of the humerus. These bony projections serve as the attachment point for the forearm musculature. Inflammation to the tendons and muscles at these attachment points can lead to medial and/or lateral epicondylitis. This can occur through a range of factors that overuse the muscles that attach to the epicondyles, such as sports or job-related duties that increase the workload of the forearm musculature and place stress on the elbow. Lateral epicondylitis is also known as “Tennis Elbow” due to its sports related association to tennis athletes, while medial epicondylitis is often referred to as “golfer's elbow.”
Risk factors
In a cross-sectional population-based study among the working population, it was found that psychological distress and bending and straightening of the elbow joint for >1hr per day were associated risk factors to epicondylitis.
Another study revealed the following potential risk factors among the working population:
Force and repetitive motions (handling tools > 1 kg, handling loads >20 kg at least 10 times/day, repetitive movements > 2 h/day) were found to be associated with the occurrence of lateral epicondylitis.
Low job control and low social support were also found to be associated with lateral epicondylitis.
Exposures of force (handling loads >5 kg, handling loads >20 kg at least 10 times/day, high hand grip forces >1 h/day), repetitiveness (repetitive movements for >2 h/day) and vibration (working with vibrating tools > 2 h/day) were associated with medial epicondylitis.
In addition to repetitive activities, obesity and smoking have been implicated as independent risk factors.
Symptoms
Tender to palpation at the medial or lateral epicondyle
Pain or difficulty with wrist flexion or extension
Diminished grip strength
Pain or burning se
Document 2:::
Arthritis is a term often used to mean any disorder that affects joints. Symptoms generally include joint pain and stiffness. Other symptoms may include redness, warmth, swelling, and decreased range of motion of the affected joints. In some types of arthritis, other organs are also affected. Onset can be gradual or sudden.
There are over 100 types of arthritis. The most common forms are osteoarthritis (degenerative joint disease) and rheumatoid arthritis. Osteoarthritis usually occurs with age and affects the fingers, knees, and hips. Rheumatoid arthritis is an autoimmune disorder that often affects the hands and feet. Other types include gout, lupus, fibromyalgia, and septic arthritis. They are all types of rheumatic disease.
Treatment may include resting the joint and alternating between applying ice and heat. Weight loss and exercise may also be useful. Recommended medications may depend on the form of arthritis. These may include pain medications such as ibuprofen and paracetamol (acetaminophen). In some circumstances, a joint replacement may be useful.
Osteoarthritis affects more than 3.8% of people, while rheumatoid arthritis affects about 0.24% of people. Gout affects about 1–2% of the Western population at some point in their lives. In Australia about 15% of people are affected by arthritis, while in the United States more than 20% have a type of arthritis. Overall the disease becomes more common with age. Arthritis is a common reason that people miss work and can result in a decreased quality of life. The term is derived from arthr- (meaning 'joint') and -itis (meaning 'inflammation').
Classification
There are several diseases where joint pain is primary, and is considered the main feature. Generally when a person has "arthritis" it means that they have one of these diseases, which include:
Hemarthrosis
Osteoarthritis
Rheumatoid arthritis
Gout and pseudo-gout
Septic arthritis
Ankylosing spondylitis
Juvenile idiopathic arthritis
Still's disease
Document 3:::
Musculoskeletal injury refers to damage of muscular or skeletal systems, which is usually due to a strenuous activity and includes damage to skeletal muscles, bones, tendons, joints, ligaments, and other affected soft tissues. In one study, roughly 25% of approximately 6300 adults received a musculoskeletal injury of some sort within 12 months—of which 83% were activity-related. Musculoskeletal injury spans into a large variety of medical specialties including orthopedic surgery (with diseases such as arthritis requiring surgery), sports medicine, emergency medicine (acute presentations of joint and muscular pain) and rheumatology (in rheumatological diseases that affect joints such as rheumatoid arthritis).
Musculoskeletal injuries can affect any part of the human body including; bones, joints, cartilages, ligaments, tendons, muscles, and other soft tissues. Symptoms include mild to severe aches, low back pain, numbness, tingling, atrophy and weakness. These injuries are a result of repetitive motions and actions over a period of time. Tendons connect muscle to bone whereas ligaments connect bone to bone. Tendons and ligaments play an active role in maintain joint stability and controls the limits of joint movements, once injured tendons and ligaments detrimentally impact motor functions. Continuous exercise or movement of a musculoskeletal injury can result in chronic inflammation with progression to permanent damage or disability.
In many cases, during the healing period after a musculoskeletal injury, a period in which the healing area will be completely immobile, a cast-induced muscle atrophy can occur. Routine sessions of physiotherapy after the cast is removed can help return strength in limp muscles or tendons. Alternately, there exist different methods of electrical stimulation of the immobile muscles which can be induced by a device placed underneath a cast, helping prevent atrophies Preventative measures include correcting or modifying one's postures a
Document 4:::
Tennis elbow, also known as lateral epicondylitis or enthesopathy of the extensor carpi radialis origin, is an enthesopathy (attachment point disease) of the origin of the extensor carpi radialis brevis on the lateral epicondyle. The outer part of the elbow becomes painful and tender. The pain may also extend into the back of the forearm. Onset of symptoms is generally gradual although they can seem sudden and be misinterpreted as an injury. Golfer's elbow is a similar condition that affects the inside of the elbow.
Enthesopathies are idiopathic, meaning science has not yet determined the cause. Enthesopathies are most common in middle age (ages 35 to 60).
It is often stated that the condition is caused by excessive use of the muscles of the back of the forearm, but this is not supported by experimental evidence and is a common misinterpretation or unhelpful thought about symptoms. It may be associated with work or sports, classically racquet sports (including paddle sports), but most people with the condition are not exposed to these activities. The diagnosis is based on the symptoms and examination. Medical imaging is not particularly useful. Signs consistent with the diagnosis include pain when a subject tries to bend back the wrist against resistance.
The natural history of untreated enthesopathy is resolution over a period of 1–2 years. Palliative (symptoms alleviating) treatment may include pain medications such as NSAIDS or acetaminophen (paracetamol), a wrist brace, or a strap over the upper forearm. The role of corticosteroid injections is debated. Recent evidence suggests corticosteroid injections may delay symptom resolution.
Signs and symptoms
Pain on the outer part of the elbow (lateral epicondyle)
Point tenderness over the lateral epicondyle—a prominent part of the bone on the outside of the elbow
Pain with resisted wrist extension or passive wrist flexion
Symptoms associated with tennis elbow include, but are not limited to, pain from the out
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
What is it called when your joints start to wear out and they become stiff and painful?
A. endometriosis
B. tendonitis
C. arthritis
D. adenitis
Answer:
|
|
sciq-5763
|
multiple_choice
|
How are the number of moles of carbon dioxide gas calculated?
|
[
"phytochemistry",
"relativistic",
"stoichiometry",
"casuistry"
] |
C
|
Relavent Documents:
Document 0:::
In chemistry, the mole map is a graphical representation of an algorithm that compares molar mass, number of particles per mole, and factors from balanced equations or other formulae.
Stoichiometry
Document 1:::
The Force Concept Inventory is a test measuring mastery of concepts commonly taught in a first semester of physics developed by Hestenes, Halloun, Wells, and Swackhamer (1985). It was the first such "concept inventory" and several others have been developed since for a variety of topics. The FCI was designed to assess student understanding of the Newtonian concepts of force. Hestenes (1998) found that while "nearly 80% of the [students completing introductory college physics courses] could state Newton's Third Law at the beginning of the course, FCI data showed that less than 15% of them fully understood it at the end". These results have been replicated in a number of studies involving students at a range of institutions (see sources section below), and have led to greater recognition in the physics education research community of the importance of students' "active engagement" with the materials to be mastered.
The 1995 version has 30 five-way multiple choice questions.
Example question (question 4):
Gender differences
The FCI shows a gender difference in favor of males that has been the subject of some research in regard to gender equity in education. Men score on average about 10% higher.
Document 2:::
The CRC Handbook of Chemistry and Physics is a comprehensive one-volume reference resource for science research. First published in 1914, it is currently () in its 103rd edition, published in 2022. It is sometimes nicknamed the "Rubber Bible" or the "Rubber Book", as CRC originally stood for "Chemical Rubber Company".
As late as the 1962–1963 edition (3604 pages) the Handbook contained myriad information for every branch of science and engineering. Sections in that edition include: Mathematics, Properties and Physical Constants, Chemical Tables, Properties of Matter, Heat, Hygrometric and Barometric Tables, Sound, Quantities and Units, and Miscellaneous. Earlier editions included sections such as "Antidotes of Poisons", "Rules for Naming Organic Compounds", "Surface Tension of Fused Salts", "Percent Composition of Anti-Freeze Solutions", "Spark-gap Voltages", "Greek Alphabet", "Musical Scales", "Pigments and Dyes", "Comparison of Tons and Pounds", "Twist Drill and Steel Wire Gauges" and "Properties of the Earth's Atmosphere at Elevations up to 160 Kilometers". Later editions focus almost exclusively on chemistry and physics topics and eliminated much of the more "common" information.
Contents by edition
22nd–44th Editions
Section A: Mathematical Tables
Section B: Properties and Physical Constants
Section C: General Chemical Tables/Specific Gravity and Properties of Matter
Section D: Heat and Hygrometry/Sound/Electricity and Magnetism/Light
Section E: Quantities and Units/Miscellaneous
Index
45th–70th Editions
Section A: Mathematical Tables
Section B: Elements and Inorganic Compounds
Section C: Organic Compounds
Section D: General Chemical
Section E: General Physical Constants
Section F: Miscellaneous
Index
71st–102nd Editions
Section 1: Basic Constants, Units, and Conversion Factors
Section 2: Symbols, Terminology, and Nomenclature
Section 3: Physical Constants of Organic Compounds
Section 4: Properties of the Elements and Inorganic Com
Document 3:::
The Gas composition of any gas can be characterised by listing the pure substances it contains, and stating for each substance its proportion of the gas mixture's molecule count.Nitrogen 78.084
Oxygen 20.9476
Argon Ar 0.934
Carbon Dioxide 0.0314
Gas composition of air
To give a familiar example, air has a composition of:
Standard Dry Air is the agreed-upon gas composition for air from which all water vapour has been removed. There are various standards bodies which publish documents that define a dry air gas composition. Each standard provides a list of constituent concentrations, a gas density at standard conditions and a molar mass.
It is extremely unlikely that the actual composition of any specific sample of air will completely agree with any definition for standard dry air. While the various definitions for standard dry air all attempt to provide realistic information about the constituents of air, the definitions are important in and of themselves because they establish a standard which can be cited in legal contracts and publications documenting measurement calculation methodologies or equations of state.
The standards below are two examples of commonly used and cited publications that provide a composition for standard dry air:
ISO TR 29922-2017 provides a definition for standard dry air which specifies an air molar mass of 28,965 46 ± 0,000 17 kg·kmol-1.
GPA 2145:2009 is published by the Gas Processors Association. It provides a molar mass for air of 28.9625 g/mol, and provides a composition for standard dry air as a footnote.
Document 4:::
GRE Subject Biochemistry, Cell and Molecular Biology was a standardized exam provided by ETS (Educational Testing Service) that was discontinued in December 2016. It is a paper-based exam and there are no computer-based versions of it. ETS places this exam three times per year: once in April, once in October and once in November. Some graduate programs in the United States recommend taking this exam, while others require this exam score as a part of the application to their graduate programs. ETS sends a bulletin with a sample practice test to each candidate after registration for the exam. There are 180 questions within the biochemistry subject test.
Scores are scaled and then reported as a number between 200 and 990; however, in recent versions of the test, the maximum and minimum reported scores have been 760 (corresponding to the 99 percentile) and 320 (1 percentile) respectively. The mean score for all test takers from July, 2009, to July, 2012, was 526 with a standard deviation of 95.
After learning that test content from editions of the GRE® Biochemistry, Cell and Molecular Biology (BCM) Test has been compromised in Israel, ETS made the decision not to administer this test worldwide in 2016–17.
Content specification
Since many students who apply to graduate programs in biochemistry do so during the first half of their fourth year, the scope of most questions is largely that of the first three years of a standard American undergraduate biochemistry curriculum. A sampling of test item content is given below:
Biochemistry (36%)
A Chemical and Physical Foundations
Thermodynamics and kinetics
Redox states
Water, pH, acid-base reactions and buffers
Solutions and equilibria
Solute-solvent interactions
Chemical interactions and bonding
Chemical reaction mechanisms
B Structural Biology: Structure, Assembly, Organization and Dynamics
Small molecules
Macromolecules (e.g., nucleic acids, polysaccharides, proteins and complex lipids)
Supramolecular complexes (e.g.
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
How are the number of moles of carbon dioxide gas calculated?
A. phytochemistry
B. relativistic
C. stoichiometry
D. casuistry
Answer:
|
|
sciq-1882
|
multiple_choice
|
What is the science that describes the ancestral and descendant connections between organisms?
|
[
"experimentally",
"phylogeny",
"organic science",
"polygamy"
] |
B
|
Relavent Documents:
Document 0:::
Merriam-Webster defines chemotaxonomy as the method of biological classification based on similarities and dissimilarity in the structure of certain compounds among the organisms being classified. Advocates argue that, as proteins are more closely controlled by genes and less subjected to natural selection than the anatomical features, they are more reliable indicators of genetic relationships. The compounds studied most are proteins, amino acids, nucleic acids, peptides etc.
Physiology is the study of working of organs in a living being. Since working of the organs involves chemicals of the body, these compounds are called biochemical evidences. The study of morphological change has shown that there are changes in the structure of animals which result in evolution. When changes take place in the structure of a living organism, they will naturally be accompanied by changes in the physiological or biochemical processes.
John Griffith Vaughan was one of the pioneers of chemotaxonomy.
Biochemical products
The body of any animal in the animal kingdom is made up of a number of chemicals. Of these, only a few biochemical products have been taken into consideration to derive evidence for evolution.
Protoplasm: Every living cell, from a bacterium to an elephant, from grasses to the blue whale, has protoplasm. Though the complexity and constituents of the protoplasm increases from lower to higher living organism, the basic compound is always the protoplasm. Evolutionary significance: From this evidence, it is clear that all living things have a common origin point or a common ancestor, which in turn had protoplasm. Its complexity increased due to changes in the mode of life and habitat.
Nucleic acids: DNA and RNA are the two types of nucleic acids present in all living organisms. They are present in the chromosomes. The structure of these acids has been found to be similar in all animals. DNA always has two chains forming a double helix, and each chain is made up of nuc
Document 1:::
The branches of science known informally as omics are various disciplines in biology whose names end in the suffix -omics, such as genomics, proteomics, metabolomics, metagenomics, phenomics and transcriptomics. Omics aims at the collective characterization and quantification of pools of biological molecules that translate into the structure, function, and dynamics of an organism or organisms.
The related suffix -ome is used to address the objects of study of such fields, such as the genome, proteome or metabolome respectively. The suffix -ome as used in molecular biology refers to a totality of some sort; it is an example of a "neo-suffix" formed by abstraction from various Greek terms in , a sequence that does not form an identifiable suffix in Greek.
Functional genomics aims at identifying the functions of as many genes as possible of a given organism. It combines
different -omics techniques such as transcriptomics and proteomics with saturated mutant collections.
Origin
The Oxford English Dictionary (OED) distinguishes three different fields of application for the -ome suffix:
in medicine, forming nouns with the sense "swelling, tumour"
in botany or zoology, forming nouns in the sense "a part of an animal or plant with a specified structure"
in cellular and molecular biology, forming nouns with the sense "all constituents considered collectively"
The -ome suffix originated as a variant of -oma, and became productive in the last quarter of the 19th century. It originally appeared in terms like sclerome or rhizome. All of these terms derive from Greek words in , a sequence that is not a single suffix, but analyzable as , the belonging to the word stem (usually a verb) and the being a genuine Greek suffix forming abstract nouns.
The OED suggests that its third definition originated as a back-formation from mitome, Early attestations include biome (1916) and genome (first coined as German Genom in 1920).
The association with chromosome in molecular bio
Document 2:::
Phylogeny in psychoanalysis is the study of the whole family or species of an organism in order to better understand the pre-history of it. It might have an unconscious influence on a patient, according to Sigmund Freud. After the possibilities of ontogeny, which is the development of the whole organism viewed from the light of occurrences during the course of its life, have been exhausted, phylogeny might shed more light on the pre-history of an organism.
The term phylogeny derives from the Greek terms phyle (φυλή) and phylon (φῦλον), denoting “tribe” and “race”; and the term genetikos (γενετικός), denoting “relative to birth”, from genesis (γένεσις) “origin” and “birth”. Phylogenetics () is the study of evolutionary relatedness among groups of organisms (e.g. species, populations), In biology this is discovered through molecular sequencing data and morphological data matrices (phylogenetics), while in psychoanalysis this is discovered by analysis of the memories of a patient and the relatives.
Document 3:::
Comparative biology uses natural variation and disparity to understand the patterns of life at all levels—from genes to communities—and the critical role of organisms in ecosystems. Comparative biology is a cross-lineage approach to understanding the phylogenetic history of individuals or higher taxa and the mechanisms and patterns that drives it. Comparative biology encompasses Evolutionary Biology, Systematics, Neontology, Paleontology, Ethology, Anthropology, and Biogeography as well as historical approaches to Developmental biology, Genomics, Physiology, Ecology and many other areas of the biological sciences. The comparative approach also has numerous applications in human health, genetics, biomedicine, and conservation biology. The biological relationships (phylogenies, pedigree) are important for comparative analyses and usually represented by a phylogenetic tree or cladogram to differentiate those features with single origins (Homology) from those with multiple origins (Homoplasy).
See also
Cladistics
Comparative Anatomy
Evolution
Evolutionary Biology
Systematics
Bioinformatics
Neontology
Paleontology
Phylogenetics
Genomics
Evolutionary biology
Comparisons
Document 4:::
A biologist is a scientist who conducts research in biology. Biologists are interested in studying life on Earth, whether it is an individual cell, a multicellular organism, or a community of interacting populations. They usually specialize in a particular branch (e.g., molecular biology, zoology, and evolutionary biology) of biology and have a specific research focus (e.g., studying malaria or cancer).
Biologists who are involved in basic research have the aim of advancing knowledge about the natural world. They conduct their research using the scientific method, which is an empirical method for testing hypotheses. Their discoveries may have applications for some specific purpose such as in biotechnology, which has the goal of developing medically useful products for humans.
In modern times, most biologists have one or more academic degrees such as a bachelor's degree plus an advanced degree like a master's degree or a doctorate. Like other scientists, biologists can be found working in different sectors of the economy such as in academia, nonprofits, private industry, or government.
History
Francesco Redi, the founder of biology, is recognized to be one of the greatest biologists of all time. Robert Hooke, an English natural philosopher, coined the term cell, suggesting plant structure's resemblance to honeycomb cells.
Charles Darwin and Alfred Wallace independently formulated the theory of evolution by natural selection, which was described in detail in Darwin's book On the Origin of Species, which was published in 1859. In it, Darwin proposed that the features of all living things, including humans, were shaped by natural processes of descent with accumulated modification leading to divergence over long periods of time. The theory of evolution in its current form affects almost all areas of biology. Separately, Gregor Mendel formulated in the principles of inheritance in 1866, which became the basis of modern genetics.
In 1953, James D. Watson and Francis
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
What is the science that describes the ancestral and descendant connections between organisms?
A. experimentally
B. phylogeny
C. organic science
D. polygamy
Answer:
|
|
sciq-2856
|
multiple_choice
|
Proper kidney function is essential for homeostasis of what level, which in turn helps ensure the functioning of enzymes?
|
[
"ions",
"ph",
"calcium",
"oxygen"
] |
B
|
Relavent Documents:
Document 0:::
Assessment of kidney function occurs in different ways, using the presence of symptoms and signs, as well as measurements using urine tests, blood tests, and medical imaging.
Functions of a healthy kidney include maintaining a person's fluid balance, maintaining an acid-base balance; regulating electrolytes including sodium, potassium, and other electrolytes; clearing toxins; regulating blood pressure; and regulating hormones, such as erythropoietin; and activation of vitamin D.
Description
The functions of the kidney include maintenance of acid-base balance; regulation of fluid balance; regulation of sodium, potassium, and other electrolytes; clearance of toxins; absorption of glucose, amino acids, and other small molecules; regulation of blood pressure; production of various hormones, such as erythropoietin; and activation of vitamin D.
The GFR is regarded as the best overall measure of the kidney's ability to carry out these numerous functions. An estimate of the GFR is used clinically to determine the degree of kidney impairment and to track the progression of the disease. The GFR, however, does not reveal the source of the kidney disease. This is accomplished by urinalysis, measurement of urine protein excretion, kidney imaging, and, if necessary, kidney biopsy.
Much of renal physiology is studied at the level of the nephron the smallest functional unit of the kidney. Each nephron begins with a filtration component that filters the blood entering the kidney. This filtrate then flows along the length of the nephron, which is a tubular structure lined by a single layer of specialized cells and surrounded by capillaries. The major functions of these lining cells are the reabsorption of water and small molecules from the filtrate into the blood, and the secretion of wastes from the blood into the urine.
Proper function of the kidney requires that it receives and adequately filters blood. This is performed at the microscopic level by many hundreds of thousa
Document 1:::
This is a table of permselectivity for different substances in the glomerulus of the kidney in renal filtration.
Document 2:::
Cystatin C or cystatin 3 (formerly gamma trace, post-gamma-globulin, or neuroendocrine basic polypeptide), a protein encoded by the CST3 gene, is mainly used as a biomarker of kidney function. Recently, it has been studied for its role in predicting new-onset or deteriorating cardiovascular disease. It also seems to play a role in brain disorders involving amyloid (a specific type of protein deposition), such as Alzheimer's disease.
In humans, all cells with a nucleus (cell core containing the DNA) produce cystatin C as a chain of 120 amino acids. It is found in virtually all tissues and body fluids. It is a potent inhibitor of lysosomal proteinases (enzymes from a special subunit of the cell that break down proteins) and probably one of the most important extracellular inhibitors of cysteine proteases (it prevents the breakdown of proteins outside the cell by a specific type of protein degrading enzymes). Cystatin C belongs to the type 2 cystatin gene family.
Role in medicine
Kidney function
Glomerular filtration rate (GFR), a marker of kidney health, is most accurately measured by injecting compounds such as inulin, radioisotopes such as 51chromium-EDTA, 125I-iothalamate, 99mTc-DTPA or radiocontrast agents such as iohexol, but these techniques are complicated, costly, time-consuming and have potential side-effects.
Creatinine is the most widely used biomarker of kidney function. It is inaccurate at detecting mild renal impairment, and levels can vary with muscle mass but not with protein intake. Urea levels might change with protein intake.
Formulas such as the Cockcroft and Gault formula and the MDRD formula (see Renal function) try to adjust for these variables.
Cystatin C has a low molecular weight (approximately 13.3 kilodaltons), and it is removed from the bloodstream by glomerular filtration in the kidneys. If kidney function and glomerular filtration rate decline, the blood levels of cystatin C rise. Cross-sectional studies (based on a single point in t
Document 3:::
The rock dove, Columbia livia, has a number of special adaptations for regulating water uptake and loss.
Challenges
C. livia pigeons drink directly by water source or indirectly from the food they ingest. They drink water through a process called double-suction mechanism. The daily diet of the pigeon places many physiological challenges that it must overcome through osmoregulation. Protein intake, for example, causes an excess of toxins of amine groups when it is broken down for energy. To regulate this excess and secrete these unwanted toxins, C. livia must remove the amine groups as uric acid. Nitrogen excretion through uric acid can be considered an advantage because it does not require a lot of water, but producing it takes more energy because of its complex molecular composition.
Pigeons adjust their drinking rates and food intake in parallel, and when adequate water is unavailable for excretion, food intake is limited to maintain water balance. As this species inhabits arid environments, research attributes this to their strong flying capabilities to reach the available water sources, not because of exceptional potential for water conservation. C. livia kidneys, like mammalian kidneys, are capable of producing urine hyperosmotic to the plasma using the processes of filtration, reabsorption, and secretion. The medullary cones function as countercurrent units that achieve the production of hyperosmotic urine. Hyperosmotic urine can be understood in light of the law of diffusion and osmolarity.
Organ of osmoregulation
Unlike a number of other bird species which have the salt gland as the primary osmoregulatory organ, C. livia does not use its salt gland. It uses the function of the kidneys to maintain homeostatic balance of ions such as sodium and potassium while preserving water quantity in the body. Filtration of the blood, reabsorption of ions and water, and secretion of uric acid are all components of the kidney's process. Columba livia has two kidneys th
Document 4:::
Chloride is an anion in the human body needed for metabolism (the process of turning food into energy). It also helps keep the body's acid-base balance. The amount of serum chloride is carefully controlled by the kidneys.
Chloride ions have important physiological roles. For instance, in the central nervous system, the inhibitory action of glycine and some of the action of GABA relies on the entry of Cl− into specific neurons. Also, the chloride-bicarbonate exchanger biological transport protein relies on the chloride ion to increase the blood's capacity of carbon dioxide, in the form of the bicarbonate ion; this is the mechanism underpinning the chloride shift occurring as the blood passes through oxygen-consuming capillary beds.
The normal blood reference range of chloride for adults in most labs is 96 to 106 milliequivalents (mEq) per liter. The normal range may vary slightly from lab to lab. Normal ranges are usually shown next to results in the lab report. A diagnostic test may use a chloridometer to determine the serum chloride level.
The North American Dietary Reference Intake recommends a daily intake of between 2300 and 3600 mg/day for 25-year-old males.
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
Proper kidney function is essential for homeostasis of what level, which in turn helps ensure the functioning of enzymes?
A. ions
B. ph
C. calcium
D. oxygen
Answer:
|
|
sciq-6681
|
multiple_choice
|
At a convergent plate boundary, when one plate is oceanic, there are large what?
|
[
"earthquakes",
"lakes",
"plateaus",
"volcanoes"
] |
D
|
Relavent Documents:
Document 0:::
Maui Nui is a modern geologists' name given to a prehistoric Hawaiian island and the corresponding modern biogeographic region. Maui Nui is composed of four modern islands: Maui, Molokaʻi, Lānaʻi, and Kahoʻolawe. Administratively, the four modern islands comprise Maui County (and a tiny part of Molokaʻi called Kalawao County). Long after the breakup of Maui Nui, the four modern islands retained plant and animal life similar to each other. Thus, Maui Nui is not only a prehistoric island but also a modern biogeographic region.
Geology
Maui Nui formed and broke up during the Pleistocene Epoch, which lasted from about 2.58 million to 11,700 years ago.
Maui Nui is built from seven shield volcanoes. The three oldest are Penguin Bank, West Molokaʻi, and East Molokaʻi, which probably range from slightly over to slightly less than 2 million years old. The four younger volcanoes are Lāna‘i, West Maui, Kaho‘olawe, and Haleakalā, which probably formed between 1.5 and 2 million years ago.
At its prime 1.2 million years ago, Maui Nui was , 50% larger than today's Hawaiʻi Island. The island of Maui Nui included four modern islands (Maui, Molokaʻi, Lānaʻi, and Kahoʻolawe) and landmass west of Molokaʻi called Penguin Bank, which is now completely submerged.
Maui Nui broke up as rising sea levels flooded the connections between the volcanoes. The breakup was complex because global sea levels rose and fell intermittently during the Quaternary glaciation. About 600,000 years ago, the connection between Molokaʻi and the island of Lāna‘i/Maui/Kahoʻolawe became intermittent. About 400,000 years ago, the connection between Lāna‘i and Maui/Kahoʻolawe also became intermittent. The connection between Maui and Kahoʻolawe was permanently broken between 200,000 and 150,000 years ago. Maui, Lāna‘i, and Molokaʻi were connected intermittently thereafter, most recently about 18,000 years ago during the Last Glacial Maximum.
Today, the sea floor between these four islands is relatively shallow
Document 1:::
The core–mantle boundary (CMB) of Earth lies between the planet's silicate mantle and its liquid iron–nickel outer core, at a depth of below Earth's surface. The boundary is observed via the discontinuity in seismic wave velocities at that depth due to the differences between the acoustic impedances of the solid mantle and the molten outer core. P-wave velocities are much slower in the outer core than in the deep mantle while S-waves do not exist at all in the liquid portion of the core. Recent evidence suggests a distinct boundary layer directly above the CMB possibly made of a novel phase of the basic perovskite mineralogy of the deep mantle named post-perovskite. Seismic tomography studies have shown significant irregularities within the boundary zone and appear to be dominated by the African and Pacific Large Low-Shear-Velocity Provinces (LLSVP).
The uppermost section of the outer core is thought to be about 500–1,800 K hotter than the overlying mantle, creating a thermal boundary layer. The boundary is thought to harbor topography, much like Earth's surface, that is supported by solid-state convection within the overlying mantle. Variations in the thermal properties of the core-mantle boundary may affect how the outer core's iron-rich fluids flow, which are ultimately responsible for Earth's magnetic field.
The D″ region
The approx. 200 km thick layer of the lower mantle directly above the boundary is referred to as the D″ region ("D double-prime" or "D prime prime") and is sometimes included in discussions regarding the core–mantle boundary zone. The D″ name originates from geophysicist Keith Bullen's designations for the Earth's layers. His system was to label each layer alphabetically, A through G, with the crust as 'A' and the inner core as 'G'. In his 1942 publication of his model, the entire lower mantle was the D layer. In 1949, Bullen found his 'D' layer to actually be two different layers. The upper part of the D layer, about 1800 km thick, was r
Document 2:::
In structural geology, a suture is a joining together along a major fault zone, of separate terranes, tectonic units that have different plate tectonic, metamorphic and paleogeographic histories. The suture is often represented on the surface by an orogen or mountain range.
Overview
In plate tectonics, sutures are the remains of subduction zones, and the terranes that are joined together are interpreted as fragments of different palaeocontinents or tectonic plates.
Outcrops of sutures can vary in width from a few hundred meters to a couple of kilometers. They can be networks of mylonitic shear zones or brittle fault zones, but are usually both. Sutures are usually associated with igneous intrusions and tectonic lenses with varying kinds of lithologies from plutonic rocks to ophiolitic fragments.
An example from Great Britain is the Iapetus Suture which, though now concealed beneath younger rocks, has been determined by geophysical means to run along a line roughly parallel with the Anglo-Scottish border and represents the joint between the former continent of Laurentia to the north and the former micro-continent of Avalonia to the south. Avalonia is in fact a plain which dips steeply northwestwards through the crust, underthrusting Laurentia.
Paleontological use
When used in paleontology, suture can also refer to fossil exoskeletons, as in the suture line, a division on a trilobite between the free cheek and the fixed cheek; this suture line allowed the trilobite to perform ecdysis (the shedding of its skin).
Document 3:::
Slab pull is a geophysical mechanism whereby the cooling and subsequent densifying of a subducting tectonic plate produces a downward force along the rest of the plate. In 1975 Forsyth and Uyeda used the inverse theory method to show that, of the many forces likely to be driving plate motion, slab pull was the strongest. Plate motion is partly driven by the weight of cold, dense plates sinking into the mantle at oceanic trenches. This force and slab suction account for almost all of the force driving plate tectonics. The ridge push at rifts contributes only 5 to 10%.
Carlson et al. (1983) in Lallemandet al. (2005) defined the slab pull force as:
Where:
K is (gravitational acceleration = 9.81 m/s2) according to McNutt (1984);
Δρ = 80 kg/m3 is the mean density difference between the slab and the surrounding asthenosphere;
L is the slab length calculated only for the part above 670 km (the upper/lower mantle boundary);
A is the slab age in Ma at the trench.
The slab pull force manifests itself between two extreme forms:
The aseismic back-arc extension as in the Izu–Bonin–Mariana Arc.
And as the Aleutian and Chile tectonics with strong earthquakes and back-arc thrusting.
Between these two examples there is the evolution of the Farallon Plate: from the huge slab width with the Nevada, the Sevier and Laramide orogenies; the Mid-Tertiary ignimbrite flare-up and later left as Juan de Fuca and Cocos plates, the Basin and Range Province under extension, with slab break off, smaller slab width, more edges and mantle return flow.
Some early models of plate tectonics envisioned the plates riding on top of convection cells like conveyor belts. However, most scientists working today believe that the asthenosphere does not directly cause motion by the friction of such basal forces. The North American Plate is nowhere being subducted, yet it is in motion. Likewise the African, Eurasian and Antarctic Plates. Ridge push is thought responsible for the motion of these plates
Document 4:::
Plume tectonics is a geoscientific theory that finds its roots in the mantle doming concept which was especially popular during the 1930s and initially did not accept major plate movements and continental drifting. It has survived from the 1970s until today in various forms and presentations. It has slowly evolved into a concept that recognises and accepts large-scale plate motions such as envisaged by plate tectonics, but placing them in a framework where large mantle plumes are the major driving force of the system. The initial followers of the concept during the first half of the 20th century are scientists like Beloussov and van Bemmelen, and recently the concept has gained interest especially in Japan, through new compiled work on palaeomagnetism, and is still advocated by the group of scientists elaboration upon Earth expansion. It is nowadays generally not accepted as the main theory to explain the driving forces of tectonic plate movements, although numerous modulations on the concept have been proposed.
The theory focuses on the movements of mantle plumes under tectonic plates, viewing them as the major driving force of movements of (parts of) the Earth's crust. In its more modern form, conceived in the 1970s, it tries to reconcile in one single geodynamic model the horizontalistic concept of plate tectonics, and the verticalistic concepts of mantle plumes, by the gravitational movement of plates away from major domes of the Earth's crust. The existence of various supercontinents in Earth history and their break-up has been associated recently with major upwellings of the mantle.
It is classified together with mantle convection as one of the mechanism that are used to explain the movements of tectonic plates. It also shows affinity with the concept of hot spots which is used in modern-day plate tectonics to generate a framework of specific mantle upwelling points that are relatively stable throughout time and are used to calibrate the plate movements usin
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
At a convergent plate boundary, when one plate is oceanic, there are large what?
A. earthquakes
B. lakes
C. plateaus
D. volcanoes
Answer:
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|
sciq-3524
|
multiple_choice
|
All the genes in all the members of a population make up its what?
|
[
"diversity",
"longevity",
"phenotype",
"gene pool"
] |
D
|
Relavent Documents:
Document 0:::
Genetics (from Ancient Greek , “genite” and that from , “origin”), a discipline of biology, is the science of heredity and variation in living organisms.
Articles (arranged alphabetically) related to genetics include:
#
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
Document 1:::
The following outline is provided as an overview of and topical guide to genetics:
Genetics – science of genes, heredity, and variation in living organisms. Genetics deals with the molecular structure and function of genes, and gene behavior in context of a cell or organism (e.g. dominance and epigenetics), patterns of inheritance from parent to offspring, and gene distribution, variation and change in populations.
Introduction to genetics
Introduction to genetics
Genetics
Chromosome
DNA
Genetic diversity
Genetic drift
Genetic variation
Genome
Heredity
Mutation
Nucleotide
RNA
Introduction to evolution
Evolution
Modern evolutionary synthesis
Transmutation of species
Natural selection
Extinction
Adaptation
Polymorphism (biology)
Gene flow
Biodiversity
Biogeography
Phylogenetic tree
Taxonomy (biology)
Mendelian inheritance
Molecular evolution
Branches of genetics
Classical genetics
Developmental genetics
Conservation genetics
Ecological genetics
Evolutionary genetics
Genetic engineering
Metagenics
Genetic epidemiology
Archaeogenetics
Archaeogenetics of the Near East
Genetics of intelligence
Genetic testing
Genomics
Human genetics
Human evolutionary genetics
Human mitochondrial genetics
Medical genetics
Microbial genetics
Molecular genetics
Neurogenetics
Population genetics
Plant genetics
Psychiatric genetics
Quantitative genetics
Statistical genetics
Multi-disciplinary fields that include genetics
Evolutionary anthropology
History of genetics
History of genetics
Natural history of genetics
History of molecular evolution
Cladistics
Transitional fossil
Extinction event
Timeline of the evolutionary history of life
History of the science of genetics
History of genetics
Ancient Concepts of Heredity
Experiments on Plant Hybridization
History of evolutionary thought
History of genetic engineering
History of genomics
History of paleontology
History of plant systematics
Neanderthal genome pro
Document 2:::
Genome-wide complex trait analysis (GCTA) Genome-based restricted maximum likelihood (GREML) is a statistical method for heritability estimation in genetics, which quantifies the total additive contribution of a set of genetic variants to a trait. GCTA is typically applied to common single nucleotide polymorphisms (SNPs) on a genotyping array (or "chip") and thus termed "chip" or "SNP" heritability.
GCTA operates by directly quantifying the chance genetic similarity of unrelated individuals and comparing it to their measured similarity on a trait; if two unrelated individuals are relatively similar genetically and also have similar trait measurements, then the measured genetics are likely to causally influence that trait, and the correlation can to some degree tell how much. This can be illustrated by plotting the squared pairwise trait differences between individuals against their estimated degree of relatedness. GCTA makes a number of modeling assumptions and whether/when these assumptions are satisfied continues to be debated.
The GCTA framework has also been extended in a number of ways: quantifying the contribution from multiple SNP categories (i.e. functional partitioning); quantifying the contribution of Gene-Environment interactions; quantifying the contribution of non-additive/non-linear effects of SNPs; and bivariate analyses of multiple phenotypes to quantify their genetic covariance (co-heritability or genetic correlation).
GCTA estimates have implications for the potential for discovery from Genome-wide Association Studies (GWAS) as well as the design and accuracy of polygenic scores. GCTA estimates from common variants are typically substantially lower than other estimates of total or narrow-sense heritability (such as from twin or kinship studies), which has contributed to the debate over the Missing heritability problem.
History
Estimation in biology/animal breeding using standard ANOVA/REML methods of variance components such as heritability,
Document 3:::
A diversity panel is a collection of genetic material or individual samples taken from a diverse population of a certain species. The idea is to illustrate the genetic and phenotypic diversity of the species.
Diversity panels exist for human populations, mouse and other organisms.
Researchers in the area of genetics often use diversity panels in order to reveal genotypes that are linked to certain traits, such as in QTL mapping with Genome-wide association study.
Those study analyze the Gene–environment interaction underneath simple and complex traits.
Examples
Human Genome Diversity Project
The Hybrid Mouse Diversity Panel
Maize NAM population (Nested association mapping)
Arabidopsis thaliana 1001 Genome project
See also
Genetics
Biodiversity
Evolution
Document 4:::
Genetics is the study of genes and tries to explain what they are and how they work. Genes are how living organisms inherit features or traits from their ancestors; for example, children usually look like their parents because they have inherited their parents' genes. Genetics tries to identify which traits are inherited and to explain how these traits are passed from generation to generation.
Some traits are part of an organism's physical appearance, such as eye color, height or weight. Other sorts of traits are not easily seen and include blood types or resistance to diseases. Some traits are inherited through genes, which is the reason why tall and thin people tend to have tall and thin children. Other traits come from interactions between genes and the environment, so a child who inherited the tendency of being tall will still be short if poorly nourished. The way our genes and environment interact to produce a trait can be complicated. For example, the chances of somebody dying of cancer or heart disease seems to depend on both their genes and their lifestyle.
Genes are made from a long molecule called DNA, which is copied and inherited across generations. DNA is made of simple units that line up in a particular order within it, carrying genetic information. The language used by DNA is called genetic code, which lets organisms read the information in the genes. This information is the instructions for the construction and operation of a living organism.
The information within a particular gene is not always exactly the same between one organism and another, so different copies of a gene do not always give exactly the same instructions. Each unique form of a single gene is called an allele. As an example, one allele for the gene for hair color could instruct the body to produce much pigment, producing black hair, while a different allele of the same gene might give garbled instructions that fail to produce any pigment, giving white hair. Mutations are random
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
All the genes in all the members of a population make up its what?
A. diversity
B. longevity
C. phenotype
D. gene pool
Answer:
|
|
ai2_arc-659
|
multiple_choice
|
Which list gives the correct order of substances from the lowest melting point to the highest?
|
[
"oxygen, water, iron",
"water, iron, oxygen",
"oxygen, iron, water",
"iron, oxygen, water"
] |
A
|
Relavent Documents:
Document 0:::
Conceptual questions or conceptual problems in science, technology, engineering, and mathematics (STEM) education are questions that can be answered based only on the knowledge of relevant concepts, rather than performing extensive calculations. They contrast with most homework and exam problems in science and engineering that typically require plugging in numerical values into previously discussed formulas. Such "plug-and-chug" numerical problems can often be solved correctly by just matching the pattern of the problem to a previously discussed problem and changing the numerical inputs, which requires significant amounts of time to perform the calculations but does not test or deepen the understanding of how the concepts and formulas should work together. Conceptual questions, therefore, provide a good complement to conventional numerical problems because they need minimal or no calculations and instead encourage the students to engage more deeply with the underlying concepts and how they relate to formulas.
Conceptual problems are often formulated as multiple-choice questions, making them easy to use during in-class discussions, particularly when utilizing active learning, peer instruction, and audience response. An example of a conceptual question in undergraduate thermodynamics is provided below:
During adiabatic expansion of an ideal gas, its temperatureincreases
decreases
stays the same
Impossible to tell/need more information
The use of conceptual questions in physics was popularized by Eric Mazur, particularly in the form of multiple-choice tests that he called ConcepTests. In recent years, multiple websites that maintain lists of conceptual questions have been created by instructors for various disciplines. Some books on physics provide many examples of conceptual questions as well.
Multiple conceptual questions can be assembled into a concept inventory to test the working knowledge of students at the beginning of a course or to track the improvement in
Document 1:::
Material is a substance or mixture of substances that constitutes an object. Materials can be pure or impure, living or non-living matter. Materials can be classified on the basis of their physical and chemical properties, or on their geological origin or biological function. Materials science is the study of materials, their properties and their applications.
Raw materials can be processed in different ways to influence their properties, by purification, shaping or the introduction of other materials. New materials can be produced from raw materials by synthesis.
In industry, materials are inputs to manufacturing processes to produce products or more complex materials.
Historical elements
Materials chart the history of humanity. The system of the three prehistoric ages (Stone Age, Bronze Age, Iron Age) were succeeded by historical ages: steel age in the 19th century, polymer age in the middle of the following century (plastic age) and silicon age in the second half of the 20th century.
Classification by use
Materials can be broadly categorized in terms of their use, for example:
Building materials are used for construction
Building insulation materials are used to retain heat within buildings
Refractory materials are used for high-temperature applications
Nuclear materials are used for nuclear power and weapons
Aerospace materials are used in aircraft and other aerospace applications
Biomaterials are used for applications interacting with living systems
Material selection is a process to determine which material should be used for a given application.
Classification by structure
The relevant structure of materials has a different length scale depending on the material. The structure and composition of a material can be determined by microscopy or spectroscopy.
Microstructure
In engineering, materials can be categorised according to their microscopic structure:
Plastics: a wide range of synthetic or semi-synthetic materials that use polymers as a main ingred
Document 2:::
This is a list of gases at standard conditions, which means substances that boil or sublime at or below and 1 atm pressure and are reasonably stable.
List
This list is sorted by boiling point of gases in ascending order, but can be sorted on different values. "sub" and "triple" refer to the sublimation point and the triple point, which are given in the case of a substance that sublimes at 1 atm; "dec" refers to decomposition. "~" means approximately.
Known as gas
The following list has substances known to be gases, but with an unknown boiling point.
Fluoroamine
Trifluoromethyl trifluoroethyl trioxide CF3OOOCF2CF3 boils between 10 and 20°
Bis-trifluoromethyl carbonate boils between −10 and +10° possibly +12, freezing −60°
Difluorodioxirane boils between −80 and −90°.
Difluoroaminosulfinyl fluoride F2NS(O)F is a gas but decomposes over several hours
Trifluoromethylsulfinyl chloride CF3S(O)Cl
Nitrosyl cyanide ?−20° blue-green gas 4343-68-4
Thiazyl chloride NSCl greenish yellow gas; trimerises.
Document 3:::
This is a list of analysis methods used in materials science. Analysis methods are listed by their acronym, if one exists.
Symbols
μSR – see muon spin spectroscopy
χ – see magnetic susceptibility
A
AAS – Atomic absorption spectroscopy
AED – Auger electron diffraction
AES – Auger electron spectroscopy
AFM – Atomic force microscopy
AFS – Atomic fluorescence spectroscopy
Analytical ultracentrifugation
APFIM – Atom probe field ion microscopy
APS – Appearance potential spectroscopy
ARPES – Angle resolved photoemission spectroscopy
ARUPS – Angle resolved ultraviolet photoemission spectroscopy
ATR – Attenuated total reflectance
B
BET – BET surface area measurement (BET from Brunauer, Emmett, Teller)
BiFC – Bimolecular fluorescence complementation
BKD – Backscatter Kikuchi diffraction, see EBSD
BRET – Bioluminescence resonance energy transfer
BSED – Back scattered electron diffraction, see EBSD
C
CAICISS – Coaxial impact collision ion scattering spectroscopy
CARS – Coherent anti-Stokes Raman spectroscopy
CBED – Convergent beam electron diffraction
CCM – Charge collection microscopy
CDI – Coherent diffraction imaging
CE – Capillary electrophoresis
CET – Cryo-electron tomography
CL – Cathodoluminescence
CLSM – Confocal laser scanning microscopy
COSY – Correlation spectroscopy
Cryo-EM – Cryo-electron microscopy
Cryo-SEM – Cryo-scanning electron microscopy
CV – Cyclic voltammetry
D
DE(T)A – Dielectric thermal analysis
dHvA – De Haas–van Alphen effect
DIC – Differential interference contrast microscopy
Dielectric spectroscopy
DLS – Dynamic light scattering
DLTS – Deep-level transient spectroscopy
DMA – Dynamic mechanical analysis
DPI – Dual polarisation interferometry
DRS – Diffuse reflection spectroscopy
DSC – Differential scanning calorimetry
DTA – Differential thermal analysis
DVS – Dynamic vapour sorption
E
EBIC – Electron beam induced current (see IBIC: ion beam induced charge)
EBS – Elastic (non-Rutherford) backscatterin
Document 4:::
While chemically pure materials have a single melting point, chemical mixtures often partially melt at the solidus temperature (TS or Tsol), and fully melt at the higher liquidus temperature (TL or Tliq). The solidus is always less than or equal to the liquidus, but they need not coincide. If a gap exists between the solidus and liquidus it is called the freezing range, and within that gap, the substance consists of a mixture of solid and liquid phases (like a slurry). Such is the case, for example, with the olivine (forsterite-fayalite) system, which is common in earth's mantle.
Definitions
In chemistry, materials science, and physics, the liquidus temperature specifies the temperature above which a material is completely liquid, and the maximum temperature at which crystals can co-exist with the melt in thermodynamic equilibrium. The solidus is the locus of temperatures (a curve on a phase diagram) below which a given substance is completely solid (crystallized). The solidus temperature, specifies the temperature below which a material is completely solid, and the minimum temperature at which a melt can co-exist with crystals in thermodynamic equilibrium.
Liquidus and solidus are mostly used for impure substances (mixtures) such as glasses, metal alloys, ceramics, rocks, and minerals. Lines of liquidus and solidus appear in the phase diagrams of binary solid solutions, as well as in eutectic systems away from the invariant point.
When distinction is irrelevant
For pure elements or compounds, e.g. pure copper, pure water, etc. the liquidus and solidus are at the same temperature, and the term melting point may be used.
There are also some mixtures which melt at a particular temperature, known as congruent melting. One example is eutectic mixture. In a eutectic system, there is particular mixing ratio where the solidus and liquidus temperatures coincide at a point known as the invariant point. At the invariant point, the mixture undergoes a eutectic reaction wh
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
Which list gives the correct order of substances from the lowest melting point to the highest?
A. oxygen, water, iron
B. water, iron, oxygen
C. oxygen, iron, water
D. iron, oxygen, water
Answer:
|
|
sciq-2126
|
multiple_choice
|
Intrusive igneous rocks cool from magma slowly in the crust and have large what?
|
[
"atoms",
"crystals",
"pores",
"coal deposits"
] |
B
|
Relavent Documents:
Document 0:::
In geology, rock (or stone) is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its chemical composition, and the way in which it is formed. Rocks form the Earth's outer solid layer, the crust, and most of its interior, except for the liquid outer core and pockets of magma in the asthenosphere. The study of rocks involves multiple subdisciplines of geology, including petrology and mineralogy. It may be limited to rocks found on Earth, or it may include planetary geology that studies the rocks of other celestial objects.
Rocks are usually grouped into three main groups: igneous rocks, sedimentary rocks and metamorphic rocks. Igneous rocks are formed when magma cools in the Earth's crust, or lava cools on the ground surface or the seabed. Sedimentary rocks are formed by diagenesis and lithification of sediments, which in turn are formed by the weathering, transport, and deposition of existing rocks. Metamorphic rocks are formed when existing rocks are subjected to such high pressures and temperatures that they are transformed without significant melting.
Humanity has made use of rocks since the earliest humans. This early period, called the Stone Age, saw the development of many stone tools. Stone was then used as a major component in the construction of buildings and early infrastructure. Mining developed to extract rocks from the Earth and obtain the minerals within them, including metals. Modern technology has allowed the development of new man-made rocks and rock-like substances, such as concrete.
Study
Geology is the study of Earth and its components, including the study of rock formations. Petrology is the study of the character and origin of rocks. Mineralogy is the study of the mineral components that create rocks. The study of rocks and their components has contributed to the geological understanding of Earth's history, the archaeological understanding of human history, and the
Document 1:::
In science and engineering the study of high pressure examines its effects on materials and the design and construction of devices, such as a diamond anvil cell, which can create high pressure. By high pressure is usually meant pressures of thousands (kilobars) or millions (megabars) of times atmospheric pressure (about 1 bar or 100,000 Pa).
History and overview
Percy Williams Bridgman received a Nobel Prize in 1946 for advancing this area of physics by two magnitudes of pressure (400 MPa to 40 GPa). The list of founding fathers of this field includes also the names of Harry George Drickamer, Tracy Hall, Francis P. Bundy, , and .
It was by applying high pressure as well as high temperature to carbon that man-made diamonds were first produced alongside many other interesting discoveries. Almost any material when subjected to high pressure will compact itself into a denser form, for example, quartz (also called silica or silicon dioxide) will first adopt a denser form known as coesite, then upon application of even higher pressure, form stishovite. These two forms of silica were first discovered by high-pressure experimenters, but then found in nature at the site of a meteor impact.
Chemical bonding is likely to change under high pressure, when the P*V term in the free energy becomes comparable to the energies of typical chemical bonds – i.e. at around 100 GPa. Among the most striking changes are metallization of oxygen at 96 GPa (rendering oxygen a superconductor), and transition of sodium from a nearly-free-electron metal to a transparent insulator at ~200 GPa. At ultimately high compression, however, all materials will metallize.
High-pressure experimentation has led to the discovery of the types of minerals which are believed to exist in the deep mantle of the Earth, such as silicate perovskite, which is thought to make up half of the Earth's bulk, and post-perovskite, which occurs at the core-mantle boundary and explains many anomalies inferred for that regio
Document 2:::
The rock cycle is a basic concept in geology that describes transitions through geologic time among the three main rock types: sedimentary, metamorphic, and igneous. Each rock type is altered when it is forced out of its equilibrium conditions. For example, an igneous rock such as basalt may break down and dissolve when exposed to the atmosphere, or melt as it is subducted under a continent. Due to the driving forces of the rock cycle, plate tectonics and the water cycle, rocks do not remain in equilibrium and change as they encounter new environments. The rock cycle explains how the three rock types are related to each other, and how processes change from one type to another over time. This cyclical aspect makes rock change a geologic cycle and, on planets containing life, a biogeochemical cycle.
Transition to igneous rock
When rocks are pushed deep under the Earth's surface, they may melt into magma. If the conditions no longer exist for the magma to stay in its liquid state, it cools and solidifies into an igneous rock. A rock that cools within the Earth is called intrusive or plutonic and cools very slowly, producing a coarse-grained texture such as the rock granite. As a result of volcanic activity, magma (which is called lava when it reaches Earth's surface) may cool very rapidly on the Earth's surface exposed to the atmosphere and are called extrusive or volcanic rocks. These rocks are fine-grained and sometimes cool so rapidly that no crystals can form and result in a natural glass, such as obsidian, however the most common fine-grained rock would be known as basalt. Any of the three main types of rocks (igneous, sedimentary, and metamorphic rocks) can melt into magma and cool into igneous rocks.
Secondary changes
Epigenetic change (secondary processes occurring at low temperatures and low pressures) may be arranged under a number of headings, each of which is typical of a group of rocks or rock-forming minerals, though usually more than one of these alt
Document 3:::
The geologic record in stratigraphy, paleontology and other natural sciences refers to the entirety of the layers of rock strata. That is, deposits laid down by volcanism or by deposition of sediment derived from weathering detritus (clays, sands etc.). This includes all its fossil content and the information it yields about the history of the Earth: its past climate, geography, geology and the evolution of life on its surface. According to the law of superposition, sedimentary and volcanic rock layers are deposited on top of each other. They harden over time to become a solidified (competent) rock column, that may be intruded by igneous rocks and disrupted by tectonic events.
Correlating the rock record
At a certain locality on the Earth's surface, the rock column provides a cross section of the natural history in the area during the time covered by the age of the rocks. This is sometimes called the rock history and gives a window into the natural history of the location that spans many geological time units such as ages, epochs, or in some cases even multiple major geologic periods—for the particular geographic region or regions. The geologic record is in no one place entirely complete for where geologic forces one age provide a low-lying region accumulating deposits much like a layer cake, in the next may have uplifted the region, and the same area is instead one that is weathering and being torn down by chemistry, wind, temperature, and water. This is to say that in a given location, the geologic record can be and is quite often interrupted as the ancient local environment was converted by geological forces into new landforms and features. Sediment core data at the mouths of large riverine drainage basins, some of which go deep thoroughly support the law of superposition.
However using broadly occurring deposited layers trapped within differently located rock columns, geologists have pieced together a system of units covering most of the geologic time scale
Document 4:::
Blood Falls is an outflow of an iron oxide–tainted plume of saltwater, flowing from the tongue of Taylor Glacier onto the ice-covered surface of West Lake Bonney in the Taylor Valley of the McMurdo Dry Valleys in Victoria Land, East Antarctica.
Iron-rich hypersaline water sporadically emerges from small fissures in the ice cascades. The saltwater source is a subglacial pool of unknown size overlain by about of ice several kilometers from its tiny outlet at Blood Falls.
The reddish deposit was found in 1911 by the Australian geologist Thomas Griffith Taylor, who first explored the valley that bears his name. The Antarctica pioneers first attributed the red color to red algae, but later it was proven to be due to iron oxides.
Geochemistry
Poorly soluble hydrous ferric oxides are deposited at the surface of ice after the ferrous ions present in the unfrozen saltwater are oxidized in contact with atmospheric oxygen. The more soluble ferrous ions initially are dissolved in old seawater trapped in an ancient pocket remaining from the Antarctic Ocean when a fjord was isolated by the glacier in its progression during the Miocene period, some 5 million years ago, when the sea level was higher than today.
Unlike most Antarctic glaciers, the Taylor Glacier is not frozen to the bedrock, probably because of the presence of salts concentrated by the crystallization of the ancient seawater imprisoned below it. Salt cryo-concentration occurred in the deep relict seawater when pure ice crystallized and expelled its dissolved salts as it cooled down because of the heat exchange of the captive liquid seawater with the enormous ice mass of the glacier. As a consequence, the trapped seawater was concentrated in brines with a salinity two to three times that of the mean ocean water. A second mechanism sometimes also explaining the formation of hypersaline brines is the water evaporation of surface lakes directly exposed to the very dry polar atmosphere in the McMurdo Dry Valleys. Th
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
Intrusive igneous rocks cool from magma slowly in the crust and have large what?
A. atoms
B. crystals
C. pores
D. coal deposits
Answer:
|
|
sciq-6932
|
multiple_choice
|
The decay rate is measured in a unit called the what?
|
[
"decay rate",
"half-life",
"radioactive decay",
"exponential decay"
] |
B
|
Relavent Documents:
Document 0:::
Decay correction is a method of estimating the amount of radioactive decay at some set time before it was actually measured.
Example of use
Researchers often want to measure, say, medical compounds in the bodies of animals. It's hard to measure them directly, so it can be chemically joined to a radionuclide - by measuring the radioactivity, you can get a good idea of how the original medical compound is being processed.
Samples may be collected and counted at short time intervals (ex: 1 and 4 hours). But they might be tested for radioactivity all at once. Decay correction is one way of working out what the radioactivity would have been at the time it was taken, rather than at the time it was tested.
For example, the isotope copper-64, commonly used in medical research, has a half-life of 12.7 hours. If you inject a large group of animals at "time zero", but measure the radioactivity in their organs at two later times, the later groups must be "decay corrected" to adjust for the decay that has occurred between the two time points.
Mathematics
The formula for decay correcting is:
where is the original activity count at time zero, is the activity at time "t", "λ" is the decay constant, and "t" is the elapsed time.
The decay constant is where "" is the half-life of the radioactive material of interest.
Example
The decay correct might be used this way: a group of 20 animals is injected with a compound of interest on a Monday at 10:00 a.m. The compound is chemically joined to the isotope copper-64, which has a known half-life of 12.7 hours, or 764 minutes. After one hour, the 5 animals in the "one hour" group are killed, dissected, and organs of interest are placed in sealed containers to await measurement. This is repeated for another 5 animals, at 2 hours, and again at 4 hours. At this point, (say, 4:00 p.m., Monday) all the organs collected so far are measured for radioactivity (a proxy of the distribution of the compound of interest). The next day
Document 1:::
In the context of radioactivity, activity or total activity (symbol A) is a physical quantity defined as the number of radioactive transformations per second that occur in a particular radionuclide. The unit of activity is the becquerel (symbol Bq), which is defined equivalent to reciprocal seconds (symbol s-1). The older, non-SI unit of activity is the curie (Ci), which is radioactive decay per second. Another unit of activity is the rutherford, which is defined as radioactive decay per second.
Specific activity (symbol a) is the activity per unit mass of a radionuclide and is a physical property of that radionuclide.
It is usually given in units of becquerel per kilogram (Bq/kg), but another commonly used unit of specific activity is the curie per gram (Ci/g).
The specific activity should not be confused with level of exposure to ionizing radiation and thus the exposure or absorbed dose, which is the quantity important in assessing the effects of ionizing radiation on humans.
Since the probability of radioactive decay for a given radionuclide within a set time interval is fixed (with some slight exceptions, see changing decay rates), the number of decays that occur in a given time of a given mass (and hence a specific number of atoms) of that radionuclide is also a fixed (ignoring statistical fluctuations).
Formulation
Relationship between λ and T1/2
Radioactivity is expressed as the decay rate of a particular radionuclide with decay constant λ and the number of atoms N:
The integral solution is described by exponential decay:
where N0 is the initial quantity of atoms at time t = 0.
Half-life T1/2 is defined as the length of time for half of a given quantity of radioactive atoms to undergo radioactive decay:
Taking the natural logarithm of both sides, the half-life is given by
Conversely, the decay constant λ can be derived from the half-life T1/2 as
Calculation of specific activity
The mass of the radionuclide is given by
where M i
Document 2:::
The decay energy is the energy change of a nucleus having undergone a radioactive decay. Radioactive decay is the process in which an unstable atomic nucleus loses energy by emitting ionizing particles and radiation. This decay, or loss of energy, results in an atom of one type (called the parent nuclide) transforming to an atom of a different type (called the daughter nuclide).
Decay calculation
The energy difference of the reactants is often written as Q:
Decay energy is usually quoted in terms of the energy units MeV (million electronvolts) or keV (thousand electronvolts):
Types of radioactive decay include
gamma ray
beta decay (decay energy is divided between the emitted electron and the neutrino which is emitted at the same time)
alpha decay
The decay energy is the mass difference Δm between the parent and the daughter atom and particles. It is equal to the energy of radiation E. If A is the radioactive activity, i.e. the number of transforming atoms per time, M the molar mass, then the radiation power P is:
or
or
Example: 60Co decays into 60Ni. The mass difference Δm is 0.003u. The radiated energy is approximately 2.8MeV. The molar weight is 59.93. The half life T of 5.27 year corresponds to the activity , where N is the number of atoms per mol, and T is the half-life. Taking care of the units the radiation power for 60Co is 17.9W/g
Radiation power in W/g for several isotopes:
60Co: 17.9
238Pu: 0.57
137Cs: 0.6
241Am: 0.1
210Po: 140 (T = 136d)
90Sr: 0.9
226Ra: 0.02
For use in radioisotope thermoelectric generators (RTGs) high decay energy combined with a long half life is desirable. To reduce the cost and weight of radiation shielding, sources that do not emit strong gamma radiation are preferred. This table gives an indication why - despite its enormous cost - with its roughly eighty year half life and low gamma emissions has become the RTG nuclide of choice. performs worse than on almost all measures, being shorter lived, a beta emitt
Document 3:::
ISO 31-10 is the part of international standard ISO 31 that defines names and symbols for quantities and units related to nuclear reactions and ionizing radiations. It gives names and symbols for 70 quantities and units. Where appropriate, conversion factors are also given.
Its definitions include:
00031-10
Radioactivity quantities
Document 4:::
In nuclear science, the decay chain refers to a series of radioactive decays of different radioactive decay products as a sequential series of transformations. It is also known as a "radioactive cascade". The typical radioisotope does not decay directly to a stable state, but rather it decays to another radioisotope. Thus there is usually a series of decays until the atom has become a stable isotope, meaning that the nucleus of the atom has reached a stable state.
Decay stages are referred to by their relationship to previous or subsequent stages. A parent isotope is one that undergoes decay to form a daughter isotope. One example of this is uranium (atomic number 92) decaying into thorium (atomic number 90). The daughter isotope may be stable or it may decay to form a daughter isotope of its own. The daughter of a daughter isotope is sometimes called a granddaughter isotope. Note that the parent isotope becomes the daughter isotope, unlike in the case of a biological parent and daughter.
The time it takes for a single parent atom to decay to an atom of its daughter isotope can vary widely, not only between different parent-daughter pairs, but also randomly between identical pairings of parent and daughter isotopes. The decay of each single atom occurs spontaneously, and the decay of an initial population of identical atoms over time t, follows a decaying exponential distribution, e−λt, where λ is called a decay constant. One of the properties of an isotope is its half-life, the time by which half of an initial number of identical parent radioisotopes can be expected statistically to have decayed to their daughters, which is inversely related to λ. Half-lives have been determined in laboratories for many radioisotopes (or radionuclides). These can range from nearly instantaneous (less than 10−21 seconds) to more than 1019 years.
The intermediate stages each emit the same amount of radioactivity as the original radioisotope (i.e., there is a one-to-one relationsh
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
The decay rate is measured in a unit called the what?
A. decay rate
B. half-life
C. radioactive decay
D. exponential decay
Answer:
|
|
sciq-5778
|
multiple_choice
|
What bone forms the upper jaw and supports the upper teeth?
|
[
"orbital bone",
"tibular bone",
"subaerial bone",
"maxillary bone"
] |
D
|
Relavent Documents:
Document 0:::
The maxilla (: maxillae ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth.<ref>Merriam-Webster Online Dictionary.</ref> The two maxillary bones are fused at the intermaxillary suture, forming the anterior nasal spine. This is similar to the mandible (lower jaw), which is also a fusion of two mandibular bones at the mandibular symphysis. The mandible is the movable part of the jaw.
Anatomy
Structure
The maxilla is a paired bone - the two maxillae unite with each other at the intermaxillary suture. The maxilla consists of:
The body of the maxilla: pyramid-shaped; has an orbital, a nasal, an infratemporal, and a facial surface; contains the maxillary sinus.
Four processes:
the zygomatic process
the frontal process
the alveolar process
the palatine process
It has three surfaces:
the anterior, posterior, medial
Features of the maxilla include:
the infraorbital sulcus, canal, and foramen
the maxillary sinus
the incisive foramen
Articulations
Each maxilla articulates with nine bones: frontal, ethmoid, nasal, zygomatic, lacrimal, and palatine bones, the vomer, the inferior nasal concha, as well as the maxilla of the other side.
Sometimes it articulates with the orbital surface, and sometimes with the lateral pterygoid plate of the sphenoid.
Development
The maxilla is ossified in membrane. Mall and Fawcett maintain that it is ossified from two centers only, one for the maxilla proper and one for the premaxilla.
These centers appear during the sixth week of prenatal development and unite in the beginning of the third month, but the suture between the two portions persists on the palate until nearly middle life. Mall states that the frontal process is developed from both centers.
The maxillary sinus appears as a shallow groove on the nasal surface of the bone about the fourth month of development, but does
Document 1:::
Dental anatomy is a field of anatomy dedicated to the study of human tooth structures. The development, appearance, and classification of teeth fall within its purview. (The function of teeth as they contact one another falls elsewhere, under dental occlusion.) Tooth formation begins before birth, and the teeth's eventual morphology is dictated during this time. Dental anatomy is also a taxonomical science: it is concerned with the naming of teeth and the structures of which they are made, this information serving a practical purpose in dental treatment.
Usually, there are 20 primary ("baby") teeth and 32 permanent teeth, the last four being third molars or "wisdom teeth", each of which may or may not grow in. Among primary teeth, 10 usually are found in the maxilla (upper jaw) and the other 10 in the mandible (lower jaw). Among permanent teeth, 16 are found in the maxilla and the other 16 in the mandible. Each tooth has specific distinguishing features.
Growing of tooth
Tooth development is the complex process by which teeth form from embryonic cells, grow, and erupt into the mouth. Although many diverse species have teeth, non-human tooth development is largely the same as in humans. For human teeth to have a healthy oral environment, enamel, dentin, cementum, and the periodontium must all develop during appropriate stages of fetal development. Primary (baby) teeth start to form between the sixth and eighth weeks in utero, and permanent teeth begin to form in the twentieth week in utero. If teeth do not start to develop at or near these times, they will not develop at all.
A significant amount of research has focused on determining the processes that initiate tooth development. It is widely accepted that there is a factor within the tissues of the first branchial arch that is necessary for the development of teeth. The tooth bud (sometimes called the tooth germ) is an aggregation of cells that eventually forms a tooth and is organized into three parts: th
Document 2:::
In anatomy, Underwood's septa (or maxillary sinus septa, singular septum) are fin-shaped projections of bone that may exist in the maxillary sinus, first described in 1910 by Arthur S. Underwood, an anatomist at King's College in London. The presence of septa at or near the floor of the sinus are of interest to the dental clinician when proposing or performing sinus floor elevation procedures because of an increased likelihood of surgical complications, such as tearing of the Schneiderian membrane.
The prevalence of Underwood's septa in relation to the floor of the maxillary sinus has been reported at nearly 32%.
Location of septa in the sinus
Underwood divided the maxillary sinus into three regions relating to zones of distinct tooth eruption activity: anterior (corresponding to the premolars), middle (corresponding to the first molar) and posterior (corresponding to the second molar). Thus, he asserted, these septa always arise between teeth and never opposite the middle of a tooth.
Different studies reveal a different predisposition for the presence of septa based on sinus region:
Anterior: Ulm, et al., Krennmair et al.
Middle: Velásquez-Plata et al., Kim et al. and González-Santana et al.
Posterior: Underwood
Primary vs. secondary septa
Recent studies have classified two types of maxillary sinus septa: primary and secondary. Primary septa are those initially described by Underwood and that form as a result of the floor of the sinus sinking along with the roots of erupting teeth; these primary septa are thus generally found in the sinus corresponding to the space between teeth, as explained by Underwood. Conversely, secondary septa form as a result of irregular pneumatization of the sinus following loss of maxillary posterior teeth. Sinus pneumatization is a poorly understood phenomenon that results in an increased volume of the maxillary sinus, generally following maxillary posterior tooth loss, at the expense of the bone which used to house the root
Document 3:::
Changes to the dental morphology and jaw are major elements of hominid evolution. These changes were driven by the types and processing of food eaten. The evolution of the jaw is thought to have facilitated encephalization, speech, and the formation of the uniquely human chin.
Background
Today, humans possess 32 permanent teeth with a dental formula of . This breaks down to two pairs of incisors, one pair of canines, two pairs of premolars, and three pairs of molars on each jaw. In modern day humans, incisors are generally spatulate with a single root while canines are also single rooted but are single cusped and conical. Premolars are bicuspid while molars are multi-cuspid. The upper molars have three roots while the lower molars have two roots.
General patterns of dental morphological evolution throughout human evolution include a reduction in facial prognathism, the presence of a Y5 cusp pattern, the formation of a parabolic palate and the loss of the diastema.
Human teeth are made of dentin and are covered by enamel in the areas that are exposed. Enamel, itself, is composed of hydroxyapatite, a calcium phosphate crystal. The various types of human teeth perform different functions. Incisors are used to cut food, canines are used to tear food, and the premolars and molars are used to crush and grind food.
History
Hominidae
Chimpanzees
According to the theory of evolution, humans evolved from a common ancestor of chimpanzees. Researchers hypothesize that the earliest hominid ancestor would have similar dental morphology to chimpanzees today. Thus, comparisons between chimpanzees and Homo sapiens could be used to identify major differences. Major characterizing features of Pan troglodytes dental morphology include the presence of peripherally located cusps, thin enamel, and strong facial prognathism.
Earliest Hominids
Sahelanthropus tchadensis
Sahelanthropus tchadensis is thought to be one of the earliest species belonging to the human lineage. Fossil
Document 4:::
Human teeth function to mechanically break down items of food by cutting and crushing them in preparation for swallowing and digesting. As such, they are considered part of the human digestive system. Humans have four types of teeth: incisors, canines, premolars, and molars, which each have a specific function. The incisors cut the food, the canines tear the food and the molars and premolars crush the food. The roots of teeth are embedded in the maxilla (upper jaw) or the mandible (lower jaw) and are covered by gums. Teeth are made of multiple tissues of varying density and hardness.
Humans, like most other mammals, are diphyodont, meaning that they develop two sets of teeth. The first set, deciduous teeth, also called "primary teeth", "baby teeth", or "milk teeth", normally eventually contains 20 teeth. Primary teeth typically start to appear ("erupt") around six months of age and this may be distracting and/or painful for the infant. However, some babies are born with one or more visible teeth, known as neonatal teeth or "natal teeth".
Anatomy
Dental anatomy is a field of anatomy dedicated to the study of tooth structure. The development, appearance, and classification of teeth fall within its field of study, though dental occlusion, or contact between teeth, does not. Dental anatomy is also a taxonomic science as it is concerned with the naming of teeth and their structures. This information serves a practical purpose for dentists, enabling them to easily identify and describe teeth and structures during treatment.
The anatomic crown of a tooth is the area covered in enamel above the cementoenamel junction (CEJ) or "neck" of the tooth. Most of the crown is composed of dentin ("dentine" in British English) with the pulp chamber inside. The crown is within bone before eruption. After eruption, it is almost always visible. The anatomic root is found below the CEJ and is covered with cementum. As with the crown, dentin composes most of the root, which normally h
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
What bone forms the upper jaw and supports the upper teeth?
A. orbital bone
B. tibular bone
C. subaerial bone
D. maxillary bone
Answer:
|
|
sciq-8823
|
multiple_choice
|
How many valence electrons does helium have?
|
[
"three",
"Five",
"two",
"six"
] |
C
|
Relavent Documents:
Document 0:::
Conceptual questions or conceptual problems in science, technology, engineering, and mathematics (STEM) education are questions that can be answered based only on the knowledge of relevant concepts, rather than performing extensive calculations. They contrast with most homework and exam problems in science and engineering that typically require plugging in numerical values into previously discussed formulas. Such "plug-and-chug" numerical problems can often be solved correctly by just matching the pattern of the problem to a previously discussed problem and changing the numerical inputs, which requires significant amounts of time to perform the calculations but does not test or deepen the understanding of how the concepts and formulas should work together. Conceptual questions, therefore, provide a good complement to conventional numerical problems because they need minimal or no calculations and instead encourage the students to engage more deeply with the underlying concepts and how they relate to formulas.
Conceptual problems are often formulated as multiple-choice questions, making them easy to use during in-class discussions, particularly when utilizing active learning, peer instruction, and audience response. An example of a conceptual question in undergraduate thermodynamics is provided below:
During adiabatic expansion of an ideal gas, its temperatureincreases
decreases
stays the same
Impossible to tell/need more information
The use of conceptual questions in physics was popularized by Eric Mazur, particularly in the form of multiple-choice tests that he called ConcepTests. In recent years, multiple websites that maintain lists of conceptual questions have been created by instructors for various disciplines. Some books on physics provide many examples of conceptual questions as well.
Multiple conceptual questions can be assembled into a concept inventory to test the working knowledge of students at the beginning of a course or to track the improvement in
Document 1:::
In mathematical psychology and education theory, a knowledge space is a combinatorial structure used to formulate mathematical models describing the progression of a human learner. Knowledge spaces were introduced in 1985 by Jean-Paul Doignon and Jean-Claude Falmagne, and remain in extensive use in the education theory. Modern applications include two computerized tutoring systems, ALEKS and the defunct RATH.
Formally, a knowledge space assumes that a domain of knowledge is a collection of concepts or skills, each of which must be eventually mastered. Not all concepts are interchangeable; some require other concepts as prerequisites. Conversely, competency at one skill may ease the acquisition of another through similarity. A knowledge space marks out which collections of skills are feasible: they can be learned without mastering any other skills. Under reasonable assumptions, the collection of feasible competencies forms the mathematical structure known as an antimatroid.
Researchers and educators usually explore the structure of a discipline's knowledge space as a latent class model.
Motivation
Knowledge Space Theory attempts to address shortcomings of standardized testing when used in educational psychometry. Common tests, such as the SAT and ACT, compress a student's knowledge into a very small range of ordinal ranks, in the process effacing the conceptual dependencies between questions. Consequently, the tests cannot distinguish between true understanding and guesses, nor can they identify a student's particular weaknesses, only the general proportion of skills mastered. The goal of knowledge space theory is to provide a language by which exams can communicate
What the student can do and
What the student is ready to learn.
Model structure
Knowledge Space Theory-based models presume that an educational subject can be modeled as a finite set of concepts, skills, or topics. Each feasible state of knowledge about is then a subset of ; the set of
Document 2:::
The Force Concept Inventory is a test measuring mastery of concepts commonly taught in a first semester of physics developed by Hestenes, Halloun, Wells, and Swackhamer (1985). It was the first such "concept inventory" and several others have been developed since for a variety of topics. The FCI was designed to assess student understanding of the Newtonian concepts of force. Hestenes (1998) found that while "nearly 80% of the [students completing introductory college physics courses] could state Newton's Third Law at the beginning of the course, FCI data showed that less than 15% of them fully understood it at the end". These results have been replicated in a number of studies involving students at a range of institutions (see sources section below), and have led to greater recognition in the physics education research community of the importance of students' "active engagement" with the materials to be mastered.
The 1995 version has 30 five-way multiple choice questions.
Example question (question 4):
Gender differences
The FCI shows a gender difference in favor of males that has been the subject of some research in regard to gender equity in education. Men score on average about 10% higher.
Document 3:::
Advanced Placement (AP) Physics C: Electricity and Magnetism (also known as AP Physics C: E&M or AP E&M) is an introductory physics course administered by the College Board as part of its Advanced Placement program. It is intended to proxy a second-semester calculus-based university course in electricity and magnetism. The content of Physics C: E&M overlaps with that of AP Physics 2, but Physics 2 is algebra-based and covers other topics outside of electromagnetism, while Physics C is calculus-based and only covers electromagnetism. Physics C: E&M may be combined with its mechanics counterpart to form a year-long course that prepares for both exams.
Course content
E&M is equivalent to an introductory college course in electricity and magnetism for physics or engineering majors. The course modules are:
Electrostatics
Conductors, capacitors, and dielectrics
Electric circuits
Magnetic fields
Electromagnetism.
Methods of calculus are used wherever appropriate in formulating physical principles and in applying them to physical problems. Therefore, students should have completed or be concurrently enrolled in a calculus class.
AP test
The course culminates in an optional exam for which high-performing students may receive some credit towards their college coursework, depending on the institution.
Registration
The AP examination for AP Physics C: Electricity and Magnetism is separate from the AP examination for AP Physics C: Mechanics. Before 2006, test-takers paid only once and were given the choice of taking either one or two parts of the Physics C test.
Format
The exam is typically administered on a Monday afternoon in May. The exam is configured in two categories: a 35-question multiple choice section and a 3-question free response section. Test takers are allowed to use an approved calculator during the entire exam. The test is weighted such that each section is worth half of the final score. This and AP Physics C: Mechanics are the shortest AP exams, with
Document 4:::
In chemistry and physics, valence electrons are electrons in the outermost shell of an atom, and that can participate in the formation of a chemical bond if the outermost shell is not closed. In a single covalent bond, a shared pair forms with both atoms in the bond each contributing one valence electron.
The presence of valence electrons can determine the element's chemical properties, such as its valence—whether it may bond with other elements and, if so, how readily and with how many. In this way, a given element's reactivity is highly dependent upon its electronic configuration. For a main-group element, a valence electron can exist only in the outermost electron shell; for a transition metal, a valence electron can also be in an inner shell.
An atom with a closed shell of valence electrons (corresponding to a noble gas configuration) tends to be chemically inert. Atoms with one or two valence electrons more than a closed shell are highly reactive due to the relatively low energy to remove the extra valence electrons to form a positive ion. An atom with one or two electrons fewer than a closed shell is reactive due to its tendency either to gain the missing valence electrons and form a negative ion, or else to share valence electrons and form a covalent bond.
Similar to a core electron, a valence electron has the ability to absorb or release energy in the form of a photon. An energy gain can trigger the electron to move (jump) to an outer shell; this is known as atomic excitation. Or the electron can even break free from its associated atom's shell; this is ionization to form a positive ion. When an electron loses energy (thereby causing a photon to be emitted), then it can move to an inner shell which is not fully occupied.
Overview
Electron configuration
The electrons that determine valence – how an atom reacts chemically – are those with the highest energy.
For a main-group element, the valence electrons are defined as those electrons residing in the e
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
How many valence electrons does helium have?
A. three
B. Five
C. two
D. six
Answer:
|
|
sciq-10992
|
multiple_choice
|
What is the term for flowering seed plants?
|
[
"angiosperms",
"spores",
"perennials",
"gymnosperms"
] |
A
|
Relavent Documents:
Document 0:::
Mesangiospermae (core angiosperms) is a clade of flowering plants (angiosperms), informally called "mesangiosperms". They are one of two main groups of angiosperms. It is a name created under the rules of the PhyloCode system of phylogenetic nomenclature. There are about 350,000 species of mesangiosperms. The mesangiosperms contain about 99.95% of the flowering plants, assuming that there are about 175 species not in this group and about 350,000 that are. While such a clade with a similar circumscription exists in the APG III system, it was not given a name.
Phylogeny
Besides the mesangiosperms, the other groups of flowering plants are Amborellales, Nymphaeales, and Austrobaileyales. These constitute a paraphyletic grade called basal angiosperms. The order names, ending in -ales are used here without reference to taxonomic rank because these groups contain only one order.
Mesangiospermae includes the following clades:
Ceratophyllales
Chloranthales
eudicots
magnoliidae
monocots
Name
The mesangiosperms are usually recognized in classification systems that do not assign groups to taxonomic rank. The name Mesangiospermae is a branch-modified node-based name in phylogenetic nomenclature. It is defined as the most inclusive crown clade containing Platanus occidentalis, but not Amborella trichopoda, Nymphaea odorata, or Austrobaileya scandens. It is sometimes written as /Mesangiospermae even though this is not required by the PhyloCode. The "clademark" slash indicates that the term is intended as phylogenetically defined.
Description
In molecular phylogenetic studies, the mesangiosperms are always strongly supported as a monophyletic group. There is no distinguishing characteristic which is found in all mature mesangiosperms but which is not found in any of the basal angiosperms. Nevertheless, the mesangiosperms are recognizable in the earliest stage of embryonic development. The ovule contains a megagametophyte, also known as an embryo sac, that is bipolar in
Document 1:::
The gymnosperms ( lit. revealed seeds) are a group of seed-producing plants that includes conifers, cycads, Ginkgo, and gnetophytes, forming the clade Gymnospermae. The term gymnosperm comes from the composite word in ( and ), literally meaning 'naked seeds'. The name is based on the unenclosed condition of their seeds (called ovules in their unfertilized state). The non-encased condition of their seeds contrasts with the seeds and ovules of flowering plants (angiosperms), which are enclosed within an ovary. Gymnosperm seeds develop either on the surface of scales or leaves, which are often modified to form cones, or on their own as in yew, Torreya, Ginkgo. Gymnosperm lifecycles involve alternation of generations. They have a dominant diploid sporophyte phase and a reduced haploid gametophyte phase which is dependent on the sporophytic phase. The term "gymnosperm" is often used in paleobotany to refer to (the paraphyletic group of) all non-angiosperm seed plants. In that case, to specify the modern monophyletic group of gymnosperms, the term Acrogymnospermae is sometimes used.
The gymnosperms and angiosperms together comprise the spermatophytes or seed plants. The gymnosperms are subdivided into five Divisions, four of which, the Cycadophyta, Ginkgophyta, Gnetophyta, and Pinophyta (also known as Coniferophyta) are still in existence while the Pteridospermatophyta are now extinct. Newer classification place the gnetophytes among the conifers.
By far the largest group of living gymnosperms are the conifers (pines, cypresses, and relatives), followed by cycads, gnetophytes (Gnetum, Ephedra and Welwitschia), and Ginkgo biloba (a single living species). About 65% of gymnosperms are dioecious, but conifers are almost all monoecious.
Document 2:::
The fossil history of flowering plants records the development of flowers and other distinctive structures of the angiosperms, now the dominant group of plants on land. The history is controversial as flowering plants appear in great diversity in the Cretaceous, with scanty and debatable records before that, creating a puzzle for evolutionary biologists that Charles Darwin named an "abominable mystery".
Paleozoic
Fossilised spores suggest that land plants (embryophytes) have existed for at least 475 million years. Early land plants reproduced sexually with flagellated, swimming sperm, like the green algae from which they evolved. An adaptation to terrestrial life was the development of upright sporangia for dispersal by spores to new habitats. This feature is lacking in the descendants of their nearest algal relatives, the Charophycean green algae. A later terrestrial adaptation took place with retention of the delicate, avascular sexual stage, the gametophyte, within the tissues of the vascular sporophyte. This occurred by spore germination within sporangia rather than spore release, as in non-seed plants. A current example of how this might have happened can be seen in the precocious spore germination in Selaginella, the spike-moss. The result for the ancestors of angiosperms and gymnosperms was enclosing the female gamete in a case, the seed.
The first seed-bearing plants were gymnosperms, like the ginkgo, and conifers (such as pines and firs). These did not produce flowers. The pollen grains (male gametophytes) of Ginkgo and cycads produce a pair of flagellated, mobile sperm cells that "swim" down the developing pollen tube to the female and her eggs.
Angiosperms appear suddenly and in great diversity in the fossil record in the Early Cretaceous. This poses such a problem for the theory of gradual evolution that Charles Darwin called it an "abominable mystery". Several groups of extinct gymnosperms, in particular seed ferns, have been proposed as the ancest
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Macroflora is a term used for all the plants occurring in a particular area that are large enough to be seen with the naked eye. It is usually synonymous with the Flora and can be contrasted with the microflora, a term used for all the bacteria and other microorganisms in an ecosystem.
Macroflora is also an informal term used by many palaeobotanists to refer to an assemblage of plant fossils as preserved in the rock. This is in contrast to the flora, which in this context refers to the assemblage of living plants that were growing in a particular area, whose fragmentary remains became entrapped within the sediment from which the rock was formed and thus became the macroflora.
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Agrostology (from Greek , agrōstis, "type of grass"; and , -logia), sometimes graminology, is the scientific study of the grasses (the family Poaceae, or Gramineae). The grasslike species of the sedge family (Cyperaceae), the rush family (Juncaceae), and the bulrush or cattail family (Typhaceae) are often included with the true grasses in the category of graminoid, although strictly speaking these are not included within the study of agrostology. In contrast to the word graminoid, the words gramineous and graminaceous are normally used to mean "of, or relating to, the true grasses (Poaceae)".
Agrostology has importance in the maintenance of wild and grazed grasslands, agriculture (crop plants such as rice, maize, sugarcane, and wheat are grasses, and many types of animal fodder are grasses), urban and environmental horticulture, turfgrass management and sod production, ecology, and conservation.
Botanists that made important contributions to agrostology include:
Jean Bosser
Aimée Antoinette Camus
Mary Agnes Chase
Eduard Hackel
Charles Edward Hubbard
A. S. Hitchcock
Ernst Gottlieb von Steudel
Otto Stapf
Joseph Dalton Hooker
Norman Loftus Bor
Jan-Frits Veldkamp
William Derek Clayton
Robert B Shaw
Thomas Arthur Cope
Grasses
Agrostology
01
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
What is the term for flowering seed plants?
A. angiosperms
B. spores
C. perennials
D. gymnosperms
Answer:
|
|
sciq-10645
|
multiple_choice
|
What kind of reactions absorb energy from their surroundings as they occur?
|
[
"endothermic",
"hydrostatic",
"autotrophic",
"exothermic"
] |
A
|
Relavent Documents:
Document 0:::
Energy flow is the flow of energy through living things within an ecosystem. All living organisms can be organized into producers and consumers, and those producers and consumers can further be organized into a food chain. Each of the levels within the food chain is a trophic level. In order to more efficiently show the quantity of organisms at each trophic level, these food chains are then organized into trophic pyramids. The arrows in the food chain show that the energy flow is unidirectional, with the head of an arrow indicating the direction of energy flow; energy is lost as heat at each step along the way.
The unidirectional flow of energy and the successive loss of energy as it travels up the food web are patterns in energy flow that are governed by thermodynamics, which is the theory of energy exchange between systems. Trophic dynamics relates to thermodynamics because it deals with the transfer and transformation of energy (originating externally from the sun via solar radiation) to and among organisms.
Energetics and the carbon cycle
The first step in energetics is photosynthesis, wherein water and carbon dioxide from the air are taken in with energy from the sun, and are converted into oxygen and glucose. Cellular respiration is the reverse reaction, wherein oxygen and sugar are taken in and release energy as they are converted back into carbon dioxide and water. The carbon dioxide and water produced by respiration can be recycled back into plants.
Energy loss can be measured either by efficiency (how much energy makes it to the next level), or by biomass (how much living material exists at those levels at one point in time, measured by standing crop). Of all the net primary productivity at the producer trophic level, in general only 10% goes to the next level, the primary consumers, then only 10% of that 10% goes on to the next trophic level, and so on up the food pyramid. Ecological efficiency may be anywhere from 5% to 20% depending on how efficient
Document 1:::
A reversible reaction is a reaction in which the conversion of reactants to products and the conversion of products to reactants occur simultaneously.
\mathit aA{} + \mathit bB <=> \mathit cC{} + \mathit dD
A and B can react to form C and D or, in the reverse reaction, C and D can react to form A and B. This is distinct from a reversible process in thermodynamics.
Weak acids and bases undergo reversible reactions. For example, carbonic acid:
H2CO3 (l) + H2O(l) ⇌ HCO3−(aq) + H3O+(aq).
The concentrations of reactants and products in an equilibrium mixture are determined by the analytical concentrations of the reagents (A and B or C and D) and the equilibrium constant, K. The magnitude of the equilibrium constant depends on the Gibbs free energy change for the reaction. So, when the free energy change is large (more than about 30 kJ mol−1), the equilibrium constant is large (log K > 3) and the concentrations of the reactants at equilibrium are very small. Such a reaction is sometimes considered to be an irreversible reaction, although small amounts of the reactants are still expected to be present in the reacting system. A truly irreversible chemical reaction is usually achieved when one of the products exits the reacting system, for example, as does carbon dioxide (volatile) in the reaction
CaCO3 + 2HCl → CaCl2 + H2O + CO2↑
History
The concept of a reversible reaction was introduced by Claude Louis Berthollet in 1803, after he had observed the formation of sodium carbonate crystals at the edge of a salt lake (one of the natron lakes in Egypt, in limestone):
2NaCl + CaCO3 → Na2CO3 + CaCl2
He recognized this as the reverse of the familiar reaction
Na2CO3 + CaCl2→ 2NaCl + CaCO3
Until then, chemical reactions were thought to always proceed in one direction. Berthollet reasoned that the excess of salt in the lake helped push the "reverse" reaction towards the formation of sodium carbonate.
In 1864, Peter Waage and Cato Maximilian Guldberg formulated their
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The energy systems language, also referred to as energese, or energy circuit language, or generic systems symbols, is a modelling language used for composing energy flow diagrams in the field of systems ecology. It was developed by Howard T. Odum and colleagues in the 1950s during studies of the tropical forests funded by the United States Atomic Energy Commission.
Design intent
The design intent of the energy systems language was to facilitate the generic depiction of energy flows through any scale system while encompassing the laws of physics, and in particular, the laws of thermodynamics (see energy transformation for an example).
In particular H.T. Odum aimed to produce a language which could facilitate the intellectual analysis, engineering synthesis and management of global systems such as the geobiosphere, and its many subsystems. Within this aim, H.T. Odum had a strong concern that many abstract mathematical models of such systems were not thermodynamically valid. Hence he used analog computers to make system models due to their intrinsic value; that is, the electronic circuits are of value for modelling natural systems which are assumed to obey the laws of energy flow, because, in themselves the circuits, like natural systems, also obey the known laws of energy flow, where the energy form is electrical. However Odum was interested not only in the electronic circuits themselves, but also in how they might be used as formal analogies for modeling other systems which also had energy flowing through them. As a result, Odum did not restrict his inquiry to the analysis and synthesis of any one system in isolation. The discipline that is most often associated with this kind of approach, together with the use of the energy systems language is known as systems ecology.
General characteristics
When applying the electronic circuits (and schematics) to modeling ecological and economic systems, Odum believed that generic categories, or characteristic modules, could
Document 3:::
In chemistry and particularly biochemistry, an energy-rich species (usually energy-rich molecule) or high-energy species (usually high-energy molecule) is a chemical species which reacts, potentially with other species found in the environment, to release chemical energy.
In particular, the term is often used for:
adenosine triphosphate (ATP) and similar molecules called high-energy phosphates, which release inorganic phosphate into the environment in an exothermic reaction with water:
ATP + → ADP + Pi ΔG°' = −30.5 kJ/mol (−7.3 kcal/mol)
fuels such as hydrocarbons, carbohydrates, lipids, proteins, and other organic molecules which react with oxygen in the environment to ultimately form carbon dioxide, water, and sometimes nitrogen, sulfates, and phosphates
molecular hydrogen
monatomic oxygen, ozone, hydrogen peroxide, singlet oxygen and other metastable or unstable species which spontaneously react without further reactants
in particular, the vast majority of free radicals
explosives such as nitroglycerin and other substances which react exothermically without requiring a second reactant
metals or metal ions which can be oxidized to release energy
This is contrasted to species that are either part of the environment (this sometimes includes diatomic triplet oxygen) or do not react with the environment (such as many metal oxides or calcium carbonate); those species are not considered energy-rich or high-energy species.
Alternative definitions
The term is often used without a definition. Some authors define the term "high-energy" to be equivalent to "chemically unstable", while others reserve the term for high-energy phosphates, such as the Great Soviet Encyclopedia which defines the term "high-energy compounds" to refer exclusively to those.
The IUPAC glossary of terms used in ecotoxicology defines a primary producer as an "organism capable of using the energy derived from light or a chemical substance in order to manufacture energy-rich organic compou
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Physical biochemistry is a branch of biochemistry that deals with the theory, techniques, and methodology used to study the physical chemistry of biomolecules.
It also deals with the mathematical approaches for the analysis of biochemical reaction and the modelling of biological systems. It provides insight into the structure of macromolecules, and how chemical structure influences the physical properties of a biological substance.
It involves the use of physics, physical chemistry principles, and methodology to study biological systems. It employs various physical chemistry techniques such as chromatography, spectroscopy, Electrophoresis, X-ray crystallography, electron microscopy, and hydrodynamics.
See also
Physical chemistry
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
What kind of reactions absorb energy from their surroundings as they occur?
A. endothermic
B. hydrostatic
C. autotrophic
D. exothermic
Answer:
|
|
scienceQA-921
|
multiple_choice
|
Select the vertebrate.
|
[
"red-kneed tarantula",
"giant octopus",
"red-tailed hawk",
"castor bean tick"
] |
C
|
Like other tarantulas, a red-kneed tarantula is an invertebrate. It does not have a backbone. It has an exoskeleton.
Like other octopuses, a giant octopus is an invertebrate. It does not have a backbone. It has a soft body.
A castor bean tick is an insect. Like other insects, a castor bean tick is an invertebrate. It does not have a backbone. It has an exoskeleton.
A red-tailed hawk is a bird. Like other birds, a red-tailed hawk is a vertebrate. It has a backbone.
|
Relavent Documents:
Document 0:::
Vertebrate zoology is the biological discipline that consists of the study of Vertebrate animals, i.e., animals with a backbone, such as fish, amphibians, reptiles, birds and mammals. Many natural history museums have departments named Vertebrate Zoology. In some cases whole museums bear this name, e.g. the Museum of Vertebrate Zoology at the University of California, Berkeley.
Subdivisions
This subdivision of zoology has many further subdivisions, including:
Ichthyology - the study of fishes.
Mammalogy - the study of mammals.
Chiropterology - the study of bats.
Primatology - the study of primates.
Ornithology - the study of birds.
Herpetology - the study of reptiles.
Batrachology - the study of amphibians.
These divisions are sometimes further divided into more specific specialties.
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Animals are multicellular, eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, have myocytes and are able to move, can reproduce sexually, and grow from a hollow sphere of cells, the blastula, during embryonic development. As of 2022, 2.16 million living animal species have been described—of which around 1.05 million are insects, over 85,000 are molluscs, and around 65,000 are vertebrates. It has been estimated there are around 7.77 million animal species. Animals range in length from to . They have complex interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology.
Most living animal species are in Bilateria, a clade whose members have a bilaterally symmetric body plan. The Bilateria include the protostomes, containing animals such as nematodes, arthropods, flatworms, annelids and molluscs, and the deuterostomes, containing the echinoderms and the chordates, the latter including the vertebrates. Life forms interpreted as early animals were present in the Ediacaran biota of the late Precambrian. Many modern animal phyla became clearly established in the fossil record as marine species during the Cambrian explosion, which began around 539 million years ago. 6,331 groups of genes common to all living animals have been identified; these may have arisen from a single common ancestor that lived 650 million years ago.
Historically, Aristotle divided animals into those with blood and those without. Carl Linnaeus created the first hierarchical biological classification for animals in 1758 with his Systema Naturae, which Jean-Baptiste Lamarck expanded into 14 phyla by 1809. In 1874, Ernst Haeckel divided the animal kingdom into the multicellular Metazoa (now synonymous with Animalia) and the Protozoa, single-celled organisms no longer considered animals. In modern times, the biological classification of animals relies on ad
Document 2:::
Animals are multicellular eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, reproduce sexually, and grow from a hollow sphere of cells, the blastula, during embryonic development. Over 1.5 million living animal species have been described—of which around 1 million are insects—but it has been estimated there are over 7 million in total. Animals range in size from 8.5 millionths of a metre to long and have complex interactions with each other and their environments, forming intricate food webs. The study of animals is called zoology.
Animals may be listed or indexed by many criteria, including taxonomy, status as endangered species, their geographical location, and their portrayal and/or naming in human culture.
By common name
List of animal names (male, female, young, and group)
By aspect
List of common household pests
List of animal sounds
List of animals by number of neurons
By domestication
List of domesticated animals
By eating behaviour
List of herbivorous animals
List of omnivores
List of carnivores
By endangered status
IUCN Red List endangered species (Animalia)
United States Fish and Wildlife Service list of endangered species
By extinction
List of extinct animals
List of extinct birds
List of extinct mammals
List of extinct cetaceans
List of extinct butterflies
By region
Lists of amphibians by region
Lists of birds by region
Lists of mammals by region
Lists of reptiles by region
By individual (real or fictional)
Real
Lists of snakes
List of individual cats
List of oldest cats
List of giant squids
List of individual elephants
List of historical horses
List of leading Thoroughbred racehorses
List of individual apes
List of individual bears
List of giant pandas
List of individual birds
List of individual bovines
List of individual cetaceans
List of individual dogs
List of oldest dogs
List of individual monkeys
List of individual pigs
List of w
Document 3:::
History of Animals (, Ton peri ta zoia historion, "Inquiries on Animals"; , "History of Animals") is one of the major texts on biology by the ancient Greek philosopher Aristotle, who had studied at Plato's Academy in Athens. It was written in the fourth century BC; Aristotle died in 322 BC.
Generally seen as a pioneering work of zoology, Aristotle frames his text by explaining that he is investigating the what (the existing facts about animals) prior to establishing the why (the causes of these characteristics). The book is thus an attempt to apply philosophy to part of the natural world. Throughout the work, Aristotle seeks to identify differences, both between individuals and between groups. A group is established when it is seen that all members have the same set of distinguishing features; for example, that all birds have feathers, wings, and beaks. This relationship between the birds and their features is recognized as a universal.
The History of Animals contains many accurate eye-witness observations, in particular of the marine biology around the island of Lesbos, such as that the octopus had colour-changing abilities and a sperm-transferring tentacle, that the young of a dogfish grow inside their mother's body, or that the male of a river catfish guards the eggs after the female has left. Some of these were long considered fanciful before being rediscovered in the nineteenth century. Aristotle has been accused of making errors, but some are due to misinterpretation of his text, and others may have been based on genuine observation. He did however make somewhat uncritical use of evidence from other people, such as travellers and beekeepers.
The History of Animals had a powerful influence on zoology for some two thousand years. It continued to be a primary source of knowledge until zoologists in the sixteenth century, such as Conrad Gessner, all influenced by Aristotle, wrote their own studies of the subject.
Context
Aristotle (384–322 BC) studied at Plat
Document 4:::
Roshd Biological Education is a quarterly science educational magazine covering recent developments in biology and biology education for a biology teacher Persian -speaking audience. Founded in 1985, it is published by The Teaching Aids Publication Bureau, Organization for Educational Planning and Research, Ministry of Education, Iran. Roshd Biological Education has an editorial board composed of Iranian biologists, experts in biology education, science journalists and biology teachers.
It is read by both biology teachers and students, as a way of launching innovations and new trends in biology education, and helping biology teachers to teach biology in better and more effective ways.
Magazine layout
As of Autumn 2012, the magazine is laid out as follows:
Editorial—often offering a view of point from editor in chief on an educational and/or biological topics.
Explore— New research methods and results on biology and/or education.
World— Reports and explores on biological education worldwide.
In Brief—Summaries of research news and discoveries.
Trends—showing how new technology is altering the way we live our lives.
Point of View—Offering personal commentaries on contemporary topics.
Essay or Interview—often with a pioneer of a biological and/or educational researcher or an influential scientific educational leader.
Muslim Biologists—Short histories of Muslim Biologists.
Environment—An article on Iranian environment and its problems.
News and Reports—Offering short news and reports events on biology education.
In Brief—Short articles explaining interesting facts.
Questions and Answers—Questions about biology concepts and their answers.
Book and periodical Reviews—About new publication on biology and/or education.
Reactions—Letter to the editors.
Editorial staff
Mohammad Karamudini, editor in chief
History
Roshd Biological Education started in 1985 together with many other magazines in other science and art. The first editor was Dr. Nouri-Dalooi, th
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
Select the vertebrate.
A. red-kneed tarantula
B. giant octopus
C. red-tailed hawk
D. castor bean tick
Answer:
|
ai2_arc-403
|
multiple_choice
|
The attachment of methyl radicals to genes helps regulate which property?
|
[
"information genes store",
"mode of gene inheritance",
"gene expression",
"gene coding system"
] |
D
|
Relavent Documents:
Document 0:::
1-Methylcytosine is a methylated form of the DNA base cytosine.
In 1-methylcytosine, a methyl group is attached to the 1st atom in the 6-atom ring. This methyl group distinguishes 1-methylcytosine from cytosine.
History
Miriam Rossi worked on the refinement of 1-methylcytosine.
1-Methylcytosine is used as a nucleobase of hachimoji DNA, in which it pairs with isoguanine.
Document 1:::
CheR proteins are part of the chemotaxis signaling mechanism which methylates the chemotaxis receptor at specific glutamate residues. Methyl transfer from the ubiquitous S-adenosyl-L-methionine (AdoMet/SAM) to either nitrogen, oxygen or carbon atoms is frequently employed in diverse organisms ranging from bacteria to plants and mammals. The reaction is catalysed by methyltransferases (Mtases) and modifies DNA, RNA, proteins and small molecules, such as catechol for regulatory purposes. The various aspects of the role of DNA methylation in prokaryotic restriction-modification systems and in a number of cellular processes i
Document 2:::
This is a list of topics in molecular biology. See also index of biochemistry articles.
Document 3:::
Nutritional epigenetics is a science that studies the effects of nutrition on gene expression and chromatin accessibility. It is a subcategory of nutritional genomics that focuses on the effects of bioactive food components on epigenetic events.
History
Changes to children’s genetic profiles caused by fetal nutrition have been observed as early as the Dutch famine of 1944-1945. Due to malnutrition in pregnant mothers, children born during this famine were more likely to exhibit health issues such as heart disease, obesity, schizophrenia, depression, and addiction.
Biologists Randy Jirtle and Robert A. Waterland became early pioneers of nutritional epigenetics after publishing their research on the effects of a pregnant mother’s diet on her offspring’s gene functions in the research journal Molecular and Cellular Biology in 2003.
Research
Researchers in nutritional epigenetics study the interaction between molecules in food and molecules that control gene expression, which leads to areas of focus such as dietary methyl groups and DNA methylation. Nutrients and bioactive food components affect epigenetics by inhibiting enzymatic activity related to DNA methylation and histone modifications. Because methyl groups are used for suppression of undesirable genes, a mother’s level of dietary methyl consumption can significantly alter her child’s gene expression, especially during early development. Furthermore, nutrition can affect methylation as the process continues throughout an individual’s adult life. Because of this, nutritional epigeneticists have studied food as a form of molecular exposure.
Bioactive food components that influence epigenetic processes range from vitamins such as A, B6, and B12 to alcohol and elements such as arsenic, cadmium, and selenium. Dietary methyl supplements such as extra folic acid and choline can also have adverse effects on epigenetic gene regulation.
Researchers have considered dietary exposure to heavy metals such as mercury and
Document 4:::
The School of Biological Sciences is a School within the Faculty Biology, Medicine and Health at The University of Manchester. Biology at University of Manchester and its precursor institutions has gone through a number of reorganizations (see History below), the latest of which was the change from a Faculty of Life Sciences to the current School.
Academics
Research
The School, though unitary for teaching, is divided into a number of broadly defined sections for research purposes, these sections consist of: Cellular Systems, Disease Systems, Molecular Systems, Neuro Systems and Tissue Systems.
Research in the School is structured into multiple research groups including the following themes:
Cell-Matrix Research (part of the Wellcome Trust Centre for Cell-Matrix Research)
Cell Organisation and Dynamics
Computational and Evolutionary Biology
Developmental Biology
Environmental Research
Eye and Vision Sciences
Gene Regulation and Cellular Biotechnology
History of Science, Technology and Medicine
Immunology and Molecular Microbiology
Molecular Cancer Studies
Neurosciences (part of the University of Manchester Neurosciences Research Institute)
Physiological Systems & Disease
Structural and Functional Systems
The School hosts a number of research centres, including: the Manchester Centre for Biophysics and Catalysis, the Wellcome Trust Centre for Cell-Matrix Research, the Centre of Excellence in Biopharmaceuticals, the Centre for the History of Science, Technology and Medicine, the Centre for Integrative Mammalian Biology, and the Healing Foundation Centre for Tissue Regeneration. The Manchester Collaborative Centre for Inflammation Research is a joint endeavour with the Faculty of Medical and Human Sciences of Manchester University and industrial partners.
Research Assessment Exercise (2008)
The faculty entered research into the units of assessment (UOA) for Biological Sciences and Pre-clinical and Human Biological Sciences. In Biological Sciences 20% of outputs
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
The attachment of methyl radicals to genes helps regulate which property?
A. information genes store
B. mode of gene inheritance
C. gene expression
D. gene coding system
Answer:
|
|
sciq-222
|
multiple_choice
|
How many naturally occurring elements are known on earth?
|
[
"60",
"90",
"87",
"85"
] |
B
|
Relavent Documents:
Document 0:::
Conceptual questions or conceptual problems in science, technology, engineering, and mathematics (STEM) education are questions that can be answered based only on the knowledge of relevant concepts, rather than performing extensive calculations. They contrast with most homework and exam problems in science and engineering that typically require plugging in numerical values into previously discussed formulas. Such "plug-and-chug" numerical problems can often be solved correctly by just matching the pattern of the problem to a previously discussed problem and changing the numerical inputs, which requires significant amounts of time to perform the calculations but does not test or deepen the understanding of how the concepts and formulas should work together. Conceptual questions, therefore, provide a good complement to conventional numerical problems because they need minimal or no calculations and instead encourage the students to engage more deeply with the underlying concepts and how they relate to formulas.
Conceptual problems are often formulated as multiple-choice questions, making them easy to use during in-class discussions, particularly when utilizing active learning, peer instruction, and audience response. An example of a conceptual question in undergraduate thermodynamics is provided below:
During adiabatic expansion of an ideal gas, its temperatureincreases
decreases
stays the same
Impossible to tell/need more information
The use of conceptual questions in physics was popularized by Eric Mazur, particularly in the form of multiple-choice tests that he called ConcepTests. In recent years, multiple websites that maintain lists of conceptual questions have been created by instructors for various disciplines. Some books on physics provide many examples of conceptual questions as well.
Multiple conceptual questions can be assembled into a concept inventory to test the working knowledge of students at the beginning of a course or to track the improvement in
Document 1:::
A pre-STEM program is a course of study at any two-year college that prepares a student to transfer to a four-year school to earn a bachelor's degree in a STEM field.
Overview
The concept of a pre-STEM program is being developed to address America's need for more college-trained professionals in science, technology, engineering, and mathematics (STEM). It is an innovation meant to fill a gap at community colleges that do not have 'major' degree paths that students identify with on their way to earning an Associates degree. Students must complete a considerable amount of STEM coursework before transferring from a two-year school to a four-year school and earn a baccalaureate degree in a STEM field. Schools with a pre-STEM program are able to identify those students and support them with STEM-specific academic and career advising, increasing the student's chances of going on to earn a STEM baccalaureate degree in a timely fashion.
With over 50% of America's college-bound students starting their college career at public or private two-year school, and with a very small proportion of students who start college at a two-year school matriculating to and earning STEM degrees from four-year schools, pre-STEM programs have great potential for broadening participation in baccalaureate STEM studies.
Example programs
The effectiveness of pre-STEM programs is being investigated by a consortium of schools in Missouri: Moberly Area Community College, St. Charles Community College, Metropolitan Community College, and Truman State University.
A larger group of schools met at the Belknap Springs Meetings in October 2009 to discuss the challenges and opportunities presented by STEM-focused partnerships between 2-year and 4-year schools. Each program represented a two-year school and a four-year school that were trying to increase the number of people who earn a baccalaureate degree in a STEM area through various means, some of which were pre-STEM programs. Other methods includes
Document 2:::
Female education in STEM refers to child and adult female representation in the educational fields of science, technology, engineering, and mathematics (STEM). In 2017, 33% of students in STEM fields were women.
The organization UNESCO has stated that this gender disparity is due to discrimination, biases, social norms and expectations that influence the quality of education women receive and the subjects they study. UNESCO also believes that having more women in STEM fields is desirable because it would help bring about sustainable development.
Current status of girls and women in STEM education
Overall trends in STEM education
Gender differences in STEM education participation are already visible in early childhood care and education in science- and math-related play, and become more pronounced at higher levels of education. Girls appear to lose interest in STEM subjects with age, particularly between early and late adolescence. This decreased interest affects participation in advanced studies at the secondary level and in higher education. Female students represent 35% of all students enrolled in STEM-related fields of study at this level globally. Differences are also observed by disciplines, with female enrollment lowest in engineering, manufacturing and construction, natural science, mathematics and statistics and ICT fields. Significant regional and country differences in female representation in STEM studies can be observed, though, suggesting the presence of contextual factors affecting girls’ and women's engagement in these fields. Women leave STEM disciplines in disproportionate numbers during their higher education studies, in their transition to the world of work and even in their career cycle.
Learning achievement in STEM education
Data on gender differences in learning achievement present a complex picture, depending on what is measured (subject, knowledge acquisition against knowledge application), the level of education/age of students, and
Document 3:::
The Force Concept Inventory is a test measuring mastery of concepts commonly taught in a first semester of physics developed by Hestenes, Halloun, Wells, and Swackhamer (1985). It was the first such "concept inventory" and several others have been developed since for a variety of topics. The FCI was designed to assess student understanding of the Newtonian concepts of force. Hestenes (1998) found that while "nearly 80% of the [students completing introductory college physics courses] could state Newton's Third Law at the beginning of the course, FCI data showed that less than 15% of them fully understood it at the end". These results have been replicated in a number of studies involving students at a range of institutions (see sources section below), and have led to greater recognition in the physics education research community of the importance of students' "active engagement" with the materials to be mastered.
The 1995 version has 30 five-way multiple choice questions.
Example question (question 4):
Gender differences
The FCI shows a gender difference in favor of males that has been the subject of some research in regard to gender equity in education. Men score on average about 10% higher.
Document 4:::
The SAT Subject Test in Biology was the name of a one-hour multiple choice test given on biology by the College Board. A student chose whether to take the test depending upon college entrance requirements for the schools in which the student is planning to apply. Until 1994, the SAT Subject Tests were known as Achievement Tests; and from 1995 until January 2005, they were known as SAT IIs. Of all SAT subject tests, the Biology E/M test was the only SAT II that allowed the test taker a choice between the ecological or molecular tests. A set of 60 questions was taken by all test takers for Biology and a choice of 20 questions was allowed between either the E or M tests. This test was graded on a scale between 200 and 800. The average for Molecular is 630 while Ecological is 591.
On January 19 2021, the College Board discontinued all SAT Subject tests, including the SAT Subject Test in Biology E/M. This was effective immediately in the United States, and the tests were to be phased out by the following summer for international students. This was done as a response to changes in college admissions due to the impact of the COVID-19 pandemic on education.
Format
This test had 80 multiple-choice questions that were to be answered in one hour. All questions had five answer choices. Students received one point for each correct answer, lost ¼ of a point for each incorrect answer, and received 0 points for questions left blank. The student's score was based entirely on his or her performance in answering the multiple-choice questions.
The questions covered a broad range of topics in general biology. There were more specific questions related respectively on ecological concepts (such as population studies and general Ecology) on the E test and molecular concepts such as DNA structure, translation, and biochemistry on the M test.
Preparation
The College Board suggested a year-long course in biology at the college preparatory level, as well as a one-year course in algebra, a
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
How many naturally occurring elements are known on earth?
A. 60
B. 90
C. 87
D. 85
Answer:
|
|
sciq-2339
|
multiple_choice
|
The structure of mitochondrion plays an important role in what?
|
[
"magnetism",
"aerobic respiration",
"cell division",
"sexual reproduction"
] |
B
|
Relavent Documents:
Document 0:::
Megamitochondria is extremely large and abnormal shapes of mitochondria seen in hepatocytes in alcoholic liver disease and in nutritional deficiencies. It can be seen in conditions of hypertrophy in cell death.
Document 1:::
Cellular components are the complex biomolecules and structures of which cells, and thus living organisms, are composed. Cells are the structural and functional units of life. The smallest organisms are single cells, while the largest organisms are assemblages of trillions of cells. DNA, double stranded macromolecule that carries the hereditary information of the cell and found in all living cells; each cell carries chromosome(s) having a distinctive DNA sequence.
Examples include macromolecules such as proteins and nucleic acids, biomolecular complexes such as a ribosome, and structures such as membranes, and organelles. While the majority of cellular components are located within the cell itself, some may exist in extracellular areas of an organism.
Cellular components may also be called biological matter or biological material. Most biological matter has the characteristics of soft matter, being governed by relatively small energies. All known life is made of biological matter. To be differentiated from other theoretical or fictional life forms, such life may be called carbon-based, cellular, organic, biological, or even simply living – as some definitions of life exclude hypothetical types of biochemistry.
See also
Cell (biology)
Cell biology
Biomolecule
Organelle
Tissue (biology)
External links
https://web.archive.org/web/20130918033010/http://bioserv.fiu.edu/~walterm/FallSpring/review1_fall05_chap_cell3.htm
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The inner mitochondrial membrane (IMM) is the mitochondrial membrane which separates the mitochondrial matrix from the intermembrane space.
Structure
The structure of the inner mitochondrial membrane is extensively folded and compartmentalized. The numerous invaginations of the membrane are called cristae, separated by crista junctions from the inner boundary membrane juxtaposed to the outer membrane. Cristae significantly increase the total membrane surface area compared to a smooth inner membrane and thereby the available working space for oxidative phosphorylation.
The inner membrane creates two compartments. The region between the inner and outer membrane, called the intermembrane space, is largely continuous with the cytosol, while the more sequestered space inside the inner membrane is called the matrix.
Cristae
For typical liver mitochondria, the area of the inner membrane is about 5 times as large as the outer membrane due to cristae. This ratio is variable and mitochondria from cells that have a greater demand for ATP, such as muscle cells, contain even more cristae. Cristae membranes are studded on the matrix side with small round protein complexes known as F1 particles, the site of proton-gradient driven ATP synthesis. Cristae affect overall chemiosmotic function of mitochondria.
Cristae junctions
Cristae and the inner boundary membranes are separated by junctions. The end of cristae are partially closed by transmembrane protein complexes that bind head to head and link opposing crista membranes in a bottleneck-like fashion. For example, deletion of the junction protein IMMT leads to a reduced inner membrane potential and impaired growth and to dramatically aberrant inner membrane structures which form concentric stacks instead of the typical invaginations.
Composition
The inner membrane of mitochondria is similar in lipid composition to the membrane of bacteria. This phenomenon can be explained by the endosymbiont hypothesis of the origin of mito
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Cell physiology is the biological study of the activities that take place in a cell to keep it alive. The term physiology refers to normal functions in a living organism. Animal cells, plant cells and microorganism cells show similarities in their functions even though they vary in structure.
General characteristics
There are two types of cells: prokaryotes and eukaryotes.
Prokaryotes were the first of the two to develop and do not have a self-contained nucleus. Their mechanisms are simpler than later-evolved eukaryotes, which contain a nucleus that envelops the cell's DNA and some organelles.
Prokaryotes
Prokaryotes have DNA located in an area called the nucleoid, which is not separated from other parts of the cell by a membrane. There are two domains of prokaryotes: bacteria and archaea. Prokaryotes have fewer organelles than eukaryotes. Both have plasma membranes and ribosomes (structures that synthesize proteins and float free in cytoplasm). Two unique characteristics of prokaryotes are fimbriae (finger-like projections on the surface of a cell) and flagella (threadlike structures that aid movement).
Eukaryotes
Eukaryotes have a nucleus where DNA is contained. They are usually larger than prokaryotes and contain many more organelles. The nucleus, the feature of a eukaryote that distinguishes it from a prokaryote, contains a nuclear envelope, nucleolus and chromatin. In cytoplasm, endoplasmic reticulum (ER) synthesizes membranes and performs other metabolic activities. There are two types, rough ER (containing ribosomes) and smooth ER (lacking ribosomes). The Golgi apparatus consists of multiple membranous sacs, responsible for manufacturing and shipping out materials such as proteins. Lysosomes are structures that use enzymes to break down substances through phagocytosis, a process that comprises endocytosis and exocytosis. In the mitochondria, metabolic processes such as cellular respiration occur. The cytoskeleton is made of fibers that support the str
Document 4:::
In the mitochondrion, the matrix is the space within the inner membrane. The word "matrix" stems from the fact that this space is viscous, compared to the relatively aqueous cytoplasm. The mitochondrial matrix contains the mitochondrial DNA, ribosomes, soluble enzymes, small organic molecules, nucleotide cofactors, and inorganic ions.[1] The enzymes in the matrix facilitate reactions responsible for the production of ATP, such as the citric acid cycle, oxidative phosphorylation, oxidation of pyruvate, and the beta oxidation of fatty acids.
The composition of the matrix based on its structures and contents produce an environment that allows the anabolic and catabolic pathways to proceed favorably. The electron transport chain and enzymes in the matrix play a large role in the citric acid cycle and oxidative phosphorylation. The citric acid cycle produces NADH and FADH2 through oxidation that will be reduced in oxidative phosphorylation to produce ATP.
The cytosolic, intermembrane space, compartment has a higher aqueous:protein content of around 3.8 μL/mg protein relative to that occurring in mitochondrial matrix where such levels typically are near 0.8 μL/mg protein. It is not known how mitochondria maintain osmotic balance across the inner mitochondrial membrane, although the membrane contains aquaporins that are believed to be conduits for regulated water transport. Mitochondrial matrix has a pH of about 7.8, which is higher than the pH of the intermembrane space of the mitochondria, which is around 7.0–7.4. Mitochondrial DNA was discovered by Nash and Margit in 1963. One to many double stranded mainly circular DNA is present in mitochondrial matrix. Mitochondrial DNA is 1% of total DNA of a cell. It is rich in guanine and cytosine content, and in humans is maternally derived. Mitochondria of mammals have 55s ribosomes.
Composition
Metabolites
The matrix is host to a wide variety of metabolites involved in processes within the matrix. The citric acid cycle inv
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
The structure of mitochondrion plays an important role in what?
A. magnetism
B. aerobic respiration
C. cell division
D. sexual reproduction
Answer:
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|
sciq-497
|
multiple_choice
|
What is the study of the similarities and differences in the embryos of different species?
|
[
"example embryology",
"prenatal biology",
"diversified embryology",
"comparative embryology"
] |
D
|
Relavent Documents:
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Comparative embryology is the branch of embryology that compares and contrasts embryos of different species, showing how all animals are related.
History
Aristotle was the earliest person in recorded history to study embryos. Observing embryos of different species, he described how animals born in eggs (oviparously) and by live birth (viviparously) developed differently. He discovered there were two main ways the egg cell divided: holoblastically, where the whole egg divided and became the creature; and meroblastically, where only part of the egg became the creature. Further advances in comparative embryology did not come until the invention of the microscope. Since then, many people, from Ernst Haeckel to Charles Darwin, have contributed to the field.
Misconceptions
Many erroneous theories were formed in the early years of comparative embryology. For example, German biologist and philosopher Ernst Haeckel proposed that all organisms went through a "re-run" of evolution he said that 'ontogeny repeats phylogeny' while in development. Haeckel believed that to become a mammal, an embryo had to begin as a single-celled organism, then evolve into a fish, then an amphibian, a reptile, and finally a mammal. The theory was widely accepted, then disproved many years later.
Objectives
The field of comparative embryology aims to understand how embryos develop, and to research the inter-relatedness of animals. It has bolstered evolutionary theory by demonstrating that all vertebrates develop similarly and have a putative common ancestor.
See also
Embryology
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Embryomics is the identification, characterization and study of the diverse cell types which arise during embryogenesis, especially as this relates to the location and developmental history of cells in the embryo. Cell type may be determined according to several criteria: location in the developing embryo, gene expression as indicated by protein and nucleic acid markers and surface antigens, and also position on the embryogenic tree.
Embryome
There are many cell markers useful in distinguishing, classifying, separating and purifying the numerous cell types present at any given time in a developing organism. These cell markers consist of select RNAs and proteins present inside, and surface antigens present on the surface of, the cells making up the embryo. For any given cell type, these RNA and protein markers reflect the genes characteristically active in that cell type. The catalog of all these cell types and their characteristic markers is known as the organism's embryome. The word is a portmanteau of embryo and genome. “Embryome” may also refer to the totality of the physical cell markers themselves.
Embryogenesis
As an embryo develops from a fertilized egg, the single egg cell splits into many cells, which grow in number and migrate to the appropriate locations inside the embryo at appropriate times during development. As the embryo's cells grow in number and migrate, they also differentiate into an increasing number of different cell types, ultimately turning into the stable, specialized cell types characteristic of the adult organism. Each of the cells in an embryo contains the same genome, characteristic of the species, but the level of activity of each of the many thousands of genes that make up the complete genome varies with, and determines, a particular cell's type (e.g. neuron, bone cell, skin cell, muscle cell, etc.).
During embryo development (embryogenesis), many cell types are present which are not present in the adult organism. These temporary c
Document 2:::
A cell type is a classification used to identify cells that share morphological or phenotypical features. A multicellular organism may contain cells of a number of widely differing and specialized cell types, such as muscle cells and skin cells, that differ both in appearance and function yet have identical genomic sequences. Cells may have the same genotype, but belong to different cell types due to the differential regulation of the genes they contain. Classification of a specific cell type is often done through the use of microscopy (such as those from the cluster of differentiation family that are commonly used for this purpose in immunology). Recent developments in single cell RNA sequencing facilitated classification of cell types based on shared gene expression patterns. This has led to the discovery of many new cell types in e.g. mouse cortex, hippocampus, dorsal root ganglion and spinal cord.
Animals have evolved a greater diversity of cell types in a multicellular body (100–150 different cell types), compared
with 10–20 in plants, fungi, and protists. The exact number of cell types is, however, undefined, and the Cell Ontology, as of 2021, lists over 2,300 different cell types.
Multicellular organisms
All higher multicellular organisms contain cells specialised for different functions. Most distinct cell types arise from a single totipotent cell that differentiates into hundreds of different cell types during the course of development. Differentiation of cells is driven by different environmental cues (such as cell–cell interaction) and intrinsic differences (such as those caused by the uneven distribution of molecules during division). Multicellular organisms are composed of cells that fall into two fundamental types: germ cells and somatic cells. During development, somatic cells will become more specialized and form the three primary germ layers: ectoderm, mesoderm, and endoderm. After formation of the three germ layers, cells will continue to special
Document 3:::
This glossary of developmental biology is a list of definitions of terms and concepts commonly used in the study of developmental biology and related disciplines in biology, including embryology and reproductive biology, primarily as they pertain to vertebrate animals and particularly to humans and other mammals. The developmental biology of invertebrates, plants, fungi, and other organisms is treated in other articles; e.g. terms relating to the reproduction and development of insects are listed in Glossary of entomology, and those relating to plants are listed in Glossary of botany.
This glossary is intended as introductory material for novices; for more specific and technical detail, see the article corresponding to each term. Additional terms relevant to vertebrate reproduction and development may also be found in Glossary of biology, Glossary of cell biology, Glossary of genetics, and Glossary of evolutionary biology.
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
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See also
Introduction to developmental biology
Outline of developmental biology
Outline of cell biology
Glossary of biology
Glossary of cell biology
Glossary of genetics
Glossary of evolutionary biology
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Mammalian embryogenesis is the process of cell division and cellular differentiation during early prenatal development which leads to the development of a mammalian embryo.
Difference from embryogenesis of lower chordates
Due to the fact that placental mammals and marsupials nourish their developing embryos via the placenta, the ovum in these species does not contain significant amounts of yolk, and the yolk sac in the embryo is relatively small in size, in comparison with both the size of the embryo itself and the size of yolk sac in embryos of comparable developmental age from lower chordates. The fact that an embryo in both placental mammals and marsupials undergoes the process of implantation, and forms the chorion with its chorionic villi, and later the placenta and umbilical cord, is also a difference from lower chordates.
The difference between a mammalian embryo and an embryo of a lower chordate animal is evident starting from blastula stage. Due to that fact, the developing mammalian embryo at this stage is called a blastocyst, not a blastula, which is more generic term.
There are also several other differences from embryogenesis in lower chordates. One such difference is that in mammalian embryos development of the central nervous system and especially the brain tends to begin at earlier stages of embryonic development and to yield more structurally advanced brain at each stage, in comparison with lower chordates. The evolutionary reason for such a change likely was that the advanced and structurally complex brain, characteristic of mammals, requires more time to develop, but the maximum time spent in utero is limited by other factors, such as relative size of the final fetus to the mother (ability of the fetus to pass mother's genital tract to be born), limited resources for the mother to nourish herself and her fetus, etc. Thus, to develop such a complex and advanced brain in the end, the mammalian embryo needed to start this process earlier and to
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
What is the study of the similarities and differences in the embryos of different species?
A. example embryology
B. prenatal biology
C. diversified embryology
D. comparative embryology
Answer:
|
|
sciq-6596
|
multiple_choice
|
Metals are good conductors of what?
|
[
"metabolism",
"electricity",
"light",
"sound"
] |
B
|
Relavent Documents:
Document 0:::
Advanced Placement (AP) Physics C: Electricity and Magnetism (also known as AP Physics C: E&M or AP E&M) is an introductory physics course administered by the College Board as part of its Advanced Placement program. It is intended to proxy a second-semester calculus-based university course in electricity and magnetism. The content of Physics C: E&M overlaps with that of AP Physics 2, but Physics 2 is algebra-based and covers other topics outside of electromagnetism, while Physics C is calculus-based and only covers electromagnetism. Physics C: E&M may be combined with its mechanics counterpart to form a year-long course that prepares for both exams.
Course content
E&M is equivalent to an introductory college course in electricity and magnetism for physics or engineering majors. The course modules are:
Electrostatics
Conductors, capacitors, and dielectrics
Electric circuits
Magnetic fields
Electromagnetism.
Methods of calculus are used wherever appropriate in formulating physical principles and in applying them to physical problems. Therefore, students should have completed or be concurrently enrolled in a calculus class.
AP test
The course culminates in an optional exam for which high-performing students may receive some credit towards their college coursework, depending on the institution.
Registration
The AP examination for AP Physics C: Electricity and Magnetism is separate from the AP examination for AP Physics C: Mechanics. Before 2006, test-takers paid only once and were given the choice of taking either one or two parts of the Physics C test.
Format
The exam is typically administered on a Monday afternoon in May. The exam is configured in two categories: a 35-question multiple choice section and a 3-question free response section. Test takers are allowed to use an approved calculator during the entire exam. The test is weighted such that each section is worth half of the final score. This and AP Physics C: Mechanics are the shortest AP exams, with
Document 1:::
Conceptual questions or conceptual problems in science, technology, engineering, and mathematics (STEM) education are questions that can be answered based only on the knowledge of relevant concepts, rather than performing extensive calculations. They contrast with most homework and exam problems in science and engineering that typically require plugging in numerical values into previously discussed formulas. Such "plug-and-chug" numerical problems can often be solved correctly by just matching the pattern of the problem to a previously discussed problem and changing the numerical inputs, which requires significant amounts of time to perform the calculations but does not test or deepen the understanding of how the concepts and formulas should work together. Conceptual questions, therefore, provide a good complement to conventional numerical problems because they need minimal or no calculations and instead encourage the students to engage more deeply with the underlying concepts and how they relate to formulas.
Conceptual problems are often formulated as multiple-choice questions, making them easy to use during in-class discussions, particularly when utilizing active learning, peer instruction, and audience response. An example of a conceptual question in undergraduate thermodynamics is provided below:
During adiabatic expansion of an ideal gas, its temperatureincreases
decreases
stays the same
Impossible to tell/need more information
The use of conceptual questions in physics was popularized by Eric Mazur, particularly in the form of multiple-choice tests that he called ConcepTests. In recent years, multiple websites that maintain lists of conceptual questions have been created by instructors for various disciplines. Some books on physics provide many examples of conceptual questions as well.
Multiple conceptual questions can be assembled into a concept inventory to test the working knowledge of students at the beginning of a course or to track the improvement in
Document 2:::
The STEM (Science, Technology, Engineering, and Mathematics) pipeline is a critical infrastructure for fostering the development of future scientists, engineers, and problem solvers. It's the educational and career pathway that guides individuals from early childhood through to advanced research and innovation in STEM-related fields.
Description
The "pipeline" metaphor is based on the idea that having sufficient graduates requires both having sufficient input of students at the beginning of their studies, and retaining these students through completion of their academic program. The STEM pipeline is a key component of workplace diversity and of workforce development that ensures sufficient qualified candidates are available to fill scientific and technical positions.
The STEM pipeline was promoted in the United States from the 1970s onwards, as “the push for STEM (science, technology, engineering, and mathematics) education appears to have grown from a concern for the low number of future professionals to fill STEM jobs and careers and economic and educational competitiveness.”
Today, this metaphor is commonly used to describe retention problems in STEM fields, called “leaks” in the pipeline. For example, the White House reported in 2012 that 80% of minority groups and women who enroll in a STEM field switch to a non-STEM field or drop out during their undergraduate education. These leaks often vary by field, gender, ethnic and racial identity, socioeconomic background, and other factors, drawing attention to structural inequities involved in STEM education and careers.
Current efforts
The STEM pipeline concept is a useful tool for programs aiming at increasing the total number of graduates, and is especially important in efforts to increase the number of underrepresented minorities and women in STEM fields. Using STEM methodology, educational policymakers can examine the quantity and retention of students at all stages of the K–12 educational process and beyo
Document 3:::
Female education in STEM refers to child and adult female representation in the educational fields of science, technology, engineering, and mathematics (STEM). In 2017, 33% of students in STEM fields were women.
The organization UNESCO has stated that this gender disparity is due to discrimination, biases, social norms and expectations that influence the quality of education women receive and the subjects they study. UNESCO also believes that having more women in STEM fields is desirable because it would help bring about sustainable development.
Current status of girls and women in STEM education
Overall trends in STEM education
Gender differences in STEM education participation are already visible in early childhood care and education in science- and math-related play, and become more pronounced at higher levels of education. Girls appear to lose interest in STEM subjects with age, particularly between early and late adolescence. This decreased interest affects participation in advanced studies at the secondary level and in higher education. Female students represent 35% of all students enrolled in STEM-related fields of study at this level globally. Differences are also observed by disciplines, with female enrollment lowest in engineering, manufacturing and construction, natural science, mathematics and statistics and ICT fields. Significant regional and country differences in female representation in STEM studies can be observed, though, suggesting the presence of contextual factors affecting girls’ and women's engagement in these fields. Women leave STEM disciplines in disproportionate numbers during their higher education studies, in their transition to the world of work and even in their career cycle.
Learning achievement in STEM education
Data on gender differences in learning achievement present a complex picture, depending on what is measured (subject, knowledge acquisition against knowledge application), the level of education/age of students, and
Document 4:::
The Science, Technology, Engineering and Mathematics Network or STEMNET is an educational charity in the United Kingdom that seeks to encourage participation at school and college in science and engineering-related subjects (science, technology, engineering, and mathematics) and (eventually) work.
History
It is based at Woolgate Exchange near Moorgate tube station in London and was established in 1996. The chief executive is Kirsten Bodley. The STEMNET offices are housed within the Engineering Council.
Function
Its chief aim is to interest children in science, technology, engineering and mathematics. Primary school children can start to have an interest in these subjects, leading secondary school pupils to choose science A levels, which will lead to a science career. It supports the After School Science and Engineering Clubs at schools. There are also nine regional Science Learning Centres.
STEM ambassadors
To promote STEM subjects and encourage young people to take up jobs in these areas, STEMNET have around 30,000 ambassadors across the UK. these come from a wide selection of the STEM industries and include TV personalities like Rob Bell.
Funding
STEMNET used to receive funding from the Department for Education and Skills. Since June 2007, it receives funding from the Department for Children, Schools and Families and Department for Innovation, Universities and Skills, since STEMNET sits on the chronological dividing point (age 16) of both of the new departments.
See also
The WISE Campaign
Engineering and Physical Sciences Research Council
National Centre for Excellence in Teaching Mathematics
Association for Science Education
Glossary of areas of mathematics
Glossary of astronomy
Glossary of biology
Glossary of chemistry
Glossary of engineering
Glossary of physics
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
Metals are good conductors of what?
A. metabolism
B. electricity
C. light
D. sound
Answer:
|
|
sciq-8249
|
multiple_choice
|
The purpose of any cooling system is to transfer what type of energy in order to keep things cool?
|
[
"thermal",
"radiation",
"physical",
"atmospheric"
] |
A
|
Relavent Documents:
Document 0:::
Thermofluids is a branch of science and engineering encompassing four intersecting fields:
Heat transfer
Thermodynamics
Fluid mechanics
Combustion
The term is a combination of "thermo", referring to heat, and "fluids", which refers to liquids, gases and vapors. Temperature, pressure, equations of state, and transport laws all play an important role in thermofluid problems. Phase transition and chemical reactions may also be important in a thermofluid context. The subject is sometimes also referred to as "thermal fluids".
Heat transfer
Heat transfer is a discipline of thermal engineering that concerns the transfer of thermal energy from one physical system to another. Heat transfer is classified into various mechanisms, such as heat conduction, convection, thermal radiation, and phase-change transfer. Engineers also consider the transfer of mass of differing chemical species, either cold or hot, to achieve heat transfer.
Sections include :
Energy transfer by heat, work and mass
Laws of thermodynamics
Entropy
Refrigeration Techniques
Properties and nature of pure substances
Applications
Engineering : Predicting and analysing the performance of machines
Thermodynamics
Thermodynamics is the science of energy conversion involving heat and other forms of energy, most notably mechanical work. It studies and interrelates the macroscopic variables, such as temperature, volume and pressure, which describe physical, thermodynamic systems.
Fluid mechanics
Fluid Mechanics the study of the physical forces at work during fluid flow. Fluid mechanics can be divided into fluid kinematics, the study of fluid motion, and fluid kinetics, the study of the effect of forces on fluid motion. Fluid mechanics can further be divided into fluid statics, the study of fluids at rest, and fluid dynamics, the study of fluids in motion. Some of its more interesting concepts include momentum and reactive forces in fluid flow and fluid machinery theory and performance.
Sections include:
Flu
Document 1:::
Thermal engineering is a specialized sub-discipline of mechanical engineering that deals with the movement of heat energy and transfer. The energy can be transferred between two mediums or transformed into other forms of energy. A thermal engineer will have knowledge of thermodynamics and the process to convert generated energy from thermal sources into chemical, mechanical, or electrical energy. Many process plants use a wide variety of machines that utilize components that use heat transfer in some way. Many plants use heat exchangers in their operations. A thermal engineer must allow the proper amount of energy to be transferred for correct use. Too much and the components could fail, too little and the system will not function at all. Thermal engineers must have an understanding of economics and the components that they will be servicing or interacting with. Some components that a thermal engineer could work with include heat exchangers, heat sinks, bi-metals strips, radiators and many more. Some systems that require a thermal engineer include; Boilers, heat pumps, water pumps, engines, and more.
Part of being a thermal engineer is to improve a current system and make it more efficient than the current system. Many industries employ thermal engineers, some main ones are the automotive manufacturing industry, commercial construction, and Heating Ventilation and Cooling industry. Job opportunities for a thermal engineer are very broad and promising.
Thermal engineering may be practiced by mechanical engineers and chemical engineers.
One or more of the following disciplines may be involved in solving a particular thermal engineering problem: Thermodynamics, Fluid mechanics, Heat transfer, or
Mass transfer.
One branch of knowledge used frequently in thermal engineering is that of thermofluids.
Applications
Boiler design
Combustion engines
Cooling systems
Cooling of computer chips
Heat exchangers
HVAC
Process Fired Heaters
Refrigeration Systems
Compressed Air Sy
Document 2:::
Chilled water is a commodity often used to cool a building's air and equipment, especially in situations where many individual rooms must be controlled separately, such as a hotel. The chilled water can be supplied by a vendor, such as a public utility, or created at the location of the building that will use it, which has been the norm.
Use
Chilled water cooling is not very different from typical residential air conditioning where water is pumped from the chiller to the air handler unit to cool the air.
Regardless of who provides it, the chilled water (between 4 and 7 °C (39-45 °F)) is pumped through an air handler, which captures the heat from the air, then disperses the air throughout the area to be cooled.
Site generated
As part of a chilled water system, the condenser water absorbs heat from the refrigerant in the condenser barrel of the water chiller and is then sent via return lines to a cooling tower, which is a heat exchange device used to transfer waste heat to the atmosphere. The extent to which the cooling tower decreases the temperature depends upon the outside temperature, the relative humidity and the atmospheric pressure. The water in the chilled water circuit will be lowered to the Wet-bulb temperature or dry-bulb temperature before proceeding to the water chiller, where it is cooled to between 4 and 7 °C and pumped to the air handler, where the cycle is repeated. The equipment required includes chillers, cooling towers, pumps and electrical control equipment. The initial capital outlay for these is substantial and maintenance costs can fluctuate. Adequate space must be included in building design for the physical plant and access to equipment.
Utility generated
The chilled water, having absorbed heat from the air, is sent via return lines back to the utility facility, where the process described in the previous section occurs. Utility generated chilled water eliminates the need for chillers and cooling towers at the property, reduces capital
Document 3:::
In fluid thermodynamics, a heat transfer fluid is a gas or liquid that takes part in heat transfer by serving as an intermediary in cooling on one side of a process, transporting and storing thermal energy, and heating on another side of a process. Heat transfer fluids are used in countless applications and industrial processes requiring heating or cooling, typically in a closed circuit and in continuous cycles. Cooling water, for instance, cools an engine, while heating water in a hydronic heating system heats the radiator in a room.
Water is the most common heat transfer fluid because of its economy, high heat capacity and favorable transport properties. However, the useful temperature range is restricted by freezing below 0 °C and boiling at elevated temperatures depending on the system pressure. Antifreeze additives can alleviate the freezing problem to some extent. However, many other heat transfer fluids have been developed and used in a huge variety of applications. For higher temperatures, oil or synthetic hydrocarbon- or silicone-based fluids offer lower vapor pressure. Molten salts and molten metals can be used for transferring and storing heat at temperatures above 300 to 400 °C where organic fluids start to decompose. Gases such as water vapor, nitrogen, argon, helium and hydrogen have been used as heat transfer fluids where liquids are not suitable. For gases the pressure typically needs to be elevated to facilitate higher flow rates with low pumping power.
In order to prevent overheating, fluid flows inside a system or a device so as to transfer the heat outside that particular device or system.
They generally have a high boiling point and a high heat capacity. High boiling point prevents the heat transfer liquids from vaporising at high temperatures. High heat capacity enables a small amount of the refrigerant to transfer a large amount of heat very efficiently.
It must be ensured that the heat transfer liquids used should not have a low boiling p
Document 4:::
A continuous cooling transformation (CCT) phase diagram is often used when heat treating steel. These diagrams are used to represent which types of phase changes will occur in a material as it is cooled at different rates. These diagrams are often more useful than time-temperature-transformation diagrams because it is more convenient to cool materials at a certain rate (temperature-variable cooling), than to cool quickly and hold at a certain temperature (isothermal cooling).
Types of continuous cooling diagrams
There are two types of continuous cooling diagrams drawn for practical purposes.
Type 1: This is the plot beginning with the transformation start point, cooling with a specific transformation fraction and ending with a transformation finish temperature for all products against transformation time for each cooling curve.
Type 2: This is the plot beginning with the transformation start point, cooling with specific transformation fraction and ending with a transformation finish temperature for all products against cooling rate or bar diameter of the specimen for each type of cooling medium..
See also
Isothermal transformation
Phase diagram
The following are multiple choice questions (with answers) about knowledge and skills in advanced master-level STEM courses.
The purpose of any cooling system is to transfer what type of energy in order to keep things cool?
A. thermal
B. radiation
C. physical
D. atmospheric
Answer:
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