allenai/sciq · Datasets at Hugging Face

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What happens to the temperature of a system during phase change?	decreases	increases	fluctuates rapidly	remains constant	This plot of temperature shows what happens to a 75 g sample of ice initially at 1 atm and −23°C as heat is added at a constant rate: A–B: heating solid ice; B–C: melting ice; C–D: heating liquid water; D– E: vaporizing water; E–F: heating steam. Thus the temperature of a system does not change during a phase change. In this example, as long as even a tiny amount of ice is present, the temperature of the system remains at 0°C during the melting process, and as long as even a small amount of liquid water is present, the temperature of the system remains at 100°C during the boiling process. The rate at which heat is added does not affect the temperature of the ice/water or water/steam mixture because the added heat is being used exclusively to overcome the attractive forces that hold the more condensed phase together. Many cooks think that food will cook faster if the heat is turned up higher so that the water boils more rapidly. Instead, the pot of water will boil to dryness sooner, but the temperature of the water does not depend on how vigorously it boils.
What is the major cause of outdoor air pollution?	manufacturing industry	electric lines	agricultural equipment	burning fossil fuels	The major cause of outdoor air pollution is the burning of fossil fuels. Fossil fuels are burned in power plants, factories, motor vehicles, and home heating systems. Ranching and using chemicals such as fertilizers also cause outdoor air pollution. Erosion of soil in farm fields, mining activities, and construction sites adds dust particles to the air as well. Some specific outdoor air pollutants are described in Table below .
Why does a metal spoon heat up quickly when placed in a hot drink?	convection	insulation	high specific heat	low specific heat	The Table below compares the specific heat of four different substances. Metals such as iron have low specific heat. It doesn’t take much energy to raise their temperature. That’s why a metal spoon heats up quickly when placed in a cup of hot coffee. Sand also has a relatively low specific heat. Water, on the other hand, has a very high specific heat. It takes a lot more energy to increase the temperature of water than sand. This explains why the sand on a beach gets hot while the water stays cool. Differences in the specific heat of water and land even affect climate. To learn how, watch the video at this URL: http://www. youtube. com/watch?v=dkBStF2Rnu4.
What does the megaspore mother cell produce after meiosis division?	two haploid megaspores	four diploid megaspores	two diploid megapores	four haploid megaspores	Watch this video (http://openstaxcollege. org/l/pollen_release) to see a cedar releasing its pollen in the wind. Female Gametophyte The female cone also has a central axis on which bracts known as megasporophylls (Figure 32.10) are present. In the female cone, megaspore mother cells are present in the megasporangium. The megaspore mother cell divides by meiosis to produce four haploid megaspores. One of the megaspores divides to form the multicellular female gametophyte, while the others divide to form the rest of the structure. The female gametophyte is contained within a structure called the archegonium.
Synaptic connections can change over time depending on what?	age	weight	diet	activity level
What is the body of a roundworm covered with?	slime	thick scales	thin epidermis	tough cuticle	Roundworms have a pseudocoelom and hydrostatic skeleton. Their body is covered with tough cuticle.
The end of the phospholipid molecule that is polar and attracts water is called what?	magnetic	cytosolic	hydrophobic	hydrophilic	Figure below shows how phospholipid molecules are arranged in a cell membrane. One end (the head) of each phospholipid molecule is polar and attracts water. This end is called hydrophilic ("water loving"). The other end (the tail) is nonpolar and repels water. This end is called hydrophobic ("water hating"). The nonpolar tails are on the inside of the membrane. The polar heads are on the outside of the membrane. These differences in polarity allow some molecules to pass through the membrane while keeping others out. You can see how this works in the video at the URL below.
What is known as the universal solvent?	vinegar	oil	air	water	The ability of a solute to dissolve in a particular solvent is called solubility . Many chemical substances are soluble in water. In fact, so many substances are soluble in water that water is called the universal solvent. Water is a strongly polar solvent, and polar solvents are better at dissolving polar solutes. Many organic compounds and other important biochemicals are polar, so they dissolve well in water. On the other hand, strongly polar solvents like water cannot dissolve strongly nonpolar solutes like oil. Did you ever try to mix oil and water? Even after being well shaken, the two substances quickly separate into distinct layers.
Any organism that causes disease is called what?	a microbe	a parasite	a virus	a pathogen	You have ten times as many bacterial cells as human cells in your body. Luckily for you, most of these bacteria are harmless. However, some of them can cause disease. Any organism that causes disease is called a pathogen . Diseases caused by bacterial pathogens include food poisoning, strep throat, and Lyme disease.
Electric generators change kinetic energy to what type of energy?	intrinsic	thermal	light	electrical	Sources of voltage include electric generators and cells. Electric generators change kinetic energy to electrical energy. Chemical cells change chemical energy to electrical energy, and solar cells change solar energy to electrical energy.
Brown algae are important commodities for what?	parasites	reptiles	fish	humans
What does the large central vacuole do?	heat water	use water	create glucose	store water	First, plant cells have a large central vacuole that holds a mixture of water, nutrients, and wastes. A plant cell's vacuole can make up 90% of the cell’s volume. The large central vacuole essentially stores water. In animal cells, vacuoles are much smaller.
What is the ratio of solutes in a solution to a volume of solvent in a solution known as?	molality	equilibrium	molarity	osmolality	Regulation of Water Intake Osmolality is the ratio of solutes in a solution to a volume of solvent in a solution. Plasma osmolality is thus the ratio of solutes to water in blood plasma. A person’s plasma osmolality value reflects his or her state of hydration. A healthy body maintains plasma osmolality within a narrow range, by employing several mechanisms that regulate both water intake and output. Drinking water is considered voluntary. So how is water intake regulated by the body? Consider someone who is experiencing dehydration, a net loss of water that results in insufficient water in blood and other tissues. The water that leaves the body, as exhaled air, sweat, or urine, is ultimately extracted from blood plasma. As the blood becomes more concentrated, the thirst response—a sequence of physiological processes—is triggered (Figure 26.10). Osmoreceptors are sensory receptors in the thirst center in the hypothalamus that monitor the concentration of solutes (osmolality) of the blood. If blood osmolality increases above its ideal value, the hypothalamus transmits signals that result in a conscious awareness of thirst. The person should (and normally does) respond by drinking water. The hypothalamus of a dehydrated person also releases antidiuretic hormone (ADH) through the posterior pituitary gland. ADH signals the kidneys to recover water from urine, effectively diluting the blood plasma. To conserve water, the hypothalamus of a dehydrated person also sends signals via the sympathetic nervous system to the salivary glands in the mouth. The signals result in a decrease in watery, serous output (and an increase in stickier, thicker mucus output). These changes in secretions result in a “dry mouth” and the sensation of thirst.
What type of rock contains concentrations of valuable minerals?	metamorphic	sedimentary	igneous	ores	A mineral deposit that contains enough minerals to be mined for profit is called an ore . Ores are rocks that contain concentrations of valuable minerals. The bauxite shown in the Figure below is a rock that contains minerals that are used to make aluminum.
How many digits do primates have on each extremity?	three	ten	four	five	Primates have five digits (fingers or toes) on each extremity. Unlike the hooves of horses or the paddles of whales, the digits of primates are relatively unspecialized. Therefore, they can be used to do a variety of tasks, including grasping branches and holding tools.
Dna is normally found within what region of a cell?	Golgi apparatus	genome sequence	mitochondria	nucleus	the nucleus. The nucleus contains one or more nucleoli, which serve as sites for ribosome synthesis. The nucleus houses the genetic material of the cell: DNA. DNA is normally found as a loosely contained structure called chromatin within the nucleus, where it is wound up and associated with a variety of histone proteins. When a cell is about to divide, the chromatin coils tightly and condenses to form chromosomes. There is a pool of cells constantly dividing within your body. The result is billions of new cells being created each day. Before any cell is ready to divide, it must replicate its DNA so that each new daughter cell will receive an exact copy of the organism’s genome. A variety of enzymes are enlisted during DNA replication. These enzymes unwind the DNA molecule, separate the two strands, and assist with the building of complementary strands along each parent strand. The original DNA strands serve as templates from which the nucleotide sequence of the new strands are determined and synthesized. When replication is completed, two identical DNA molecules exist. Each one contains one original strand and one newly synthesized complementary strand.
Water and carbon dioxide molecules are reactants in what plant process?	glycolysis	digestion	breathing	photosynthesis	Water and carbon dioxide molecules are reactants in the process of photosynthesis. Does this mean they are “food” for plants, algae, and blue-green bacteria? Use the definition of “food” to answer this question.
Gene therapy is a type of what kind of engineering?	chemical engineering	mechanical engineering	electrical engineering	genetic engineering	Biotechnology in Medicine and Agriculture It is easy to see how biotechnology can be used for medicinal purposes. Knowledge of the genetic makeup of our species, the genetic basis of heritable diseases, and the invention of technology to manipulate and fix mutant genes provides methods to treat the disease. Biotechnology in agriculture can enhance resistance to disease, pest, and environmental stress, and improve both crop yield and quality. Genetic Diagnosis and Gene Therapy The process of testing for suspected genetic defects before administering treatment is called genetic diagnosis by genetic testing. Depending on the inheritance patterns of a disease-causing gene, family members are advised to undergo genetic testing. For example, women diagnosed with breast cancer are usually advised to have a biopsy so that the medical team can determine the genetic basis of cancer development. Treatment plans are based on the findings of genetic tests that determine the type of cancer. If the cancer is caused by inherited gene mutations, other female relatives are also advised to undergo genetic testing and periodic screening for breast cancer. Genetic testing is also offered for fetuses (or embryos with in vitro fertilization) to determine the presence or absence of disease-causing genes in families with specific debilitating diseases. Gene therapy is a genetic engineering technique used to cure disease. In its simplest form, it involves the introduction of a good gene at a random location in the genome to aid the cure of a disease that is caused by a mutated gene. The good gene is usually introduced into diseased cells as part of a vector transmitted by a virus that can infect the host cell and deliver the foreign DNA (Figure 17.9). More advanced forms of gene therapy try to correct the mutation at the original site in the genome, such as is the case with treatment of severe combined immunodeficiency (SCID).
What is mass number?	the total number of protons and chondrichthyes in a nucleus	to total number of electrons and neutrons in a nucleus	to total number of protons and electrons in a nucleus	the total number of protons and neutrons in a nucleus	All oxygen atoms have eight protons, and most have eight neutrons as well. What is the mass number of an oxygen isotope that has nine neutrons? What is the name of this isotope?.
What rises through solid rocks where conditions are right?	nitrogen	crystals	water	magma	Lithospheric plates do a lot of moving on Earth's surface. Slabs of lithosphere smash into each other. They move sideways past each other along faults. Where conditions are right, magma rises through solid rock. It's no wonder that rocks experience stress! Rocks respond differently to different types of stress and under different conditions.
What is the connecting piece of a sperm packed with?	Gelatin	glucose	protein	mitochondria	The connecting piece of the sperm is packed with mitochondria. Mitochondria are organelles in cells that produce energy. Sperm use the energy to move.
What is a diagram that shows a single way that energy flows throughout an ecosystem?	water cycle	fuel chain	dependent chain	food chain	A food chain is a simple diagram that shows one way energy flows through an ecosystem. Pictured below is an example of a food chain ( Figure below ). Producers form the base of all food chains. The consumers that eat producers are called primary consumers. The consumers that eat primary consumers are secondary consumers. This chain can continue to multiple levels.
Different colors of light differ in terms of which important attribute?	frequencies	lenses	prisms	wavelengths	Nobody really has such colorful eyes! The colors were added digitally after the photo was taken. They represent all the different colors of light. Light is a form of energy that travels in waves. Light of different colors has different wavelengths.
Ion drives have low thrust but high what?	tolerance	power	acceleration	efficiency	Ion drives have low thrust but high efficiency. They have already been used on several space missions, including NASA’s Deep Space 1spacecraft and Japan’sHayabusa asteroid sampling probe. Source: Photo courtesy of NASA,http://commons. wikimedia. org/wiki/File:Ion_Engine_Test_Firing_-_GPN2000-000482.
For most waves, energy is proportional to what, a term that describes the height of the wave?	wave threshold	wave frequency	wave volume	wave amplitude	Light also behaves like a package of energy. It turns out that for light, the energy of the “package” of energy is proportional to its frequency. (For most waves, energy is proportional to wave amplitude, or the height of the wave. ) The mathematical equation that relates the energy (E) of light to its frequency is.
What are the primary causes of bone fractures?	step impact or bending	overuse	spiral impact or bending	sideways impact or bending	Each ionic compound has its own unique name that comes from the names of the ions.
Water is polar and has electrically charged ends, so it is attracted to the oppositely charged end of a phospholipid molecule, which is described by what term meaning "water-loving"?	cytosolic	aqueous	hydrophobic	hydrophilic	One end of each phospholipid molecule is polar, so it has a partial electric charge. Water is also polar and has electrically charged ends, so it is attracted to the oppositely charged end of a phospholipid molecule. This end of the phospholipid molecule is described as hydrophilic, which means “water loving. ”.
What is produced when a base is dissolved in water?	ingredient ions	alkaline ions	synthesis ions	hydroxide ions	Acids are ionic compounds that produce positively charged hydrogen ions (H + ) when dissolved in water. Acids taste sour and react with metals. Bases are ionic compounds that produce negatively charged hydroxide ions (OH - ) when dissolved in water. Bases taste bitter and do not react with metals. Examples of acids are vinegar and battery acid. The acid in vinegar is weak enough to safely eat on a salad. The acid in a car battery is strong enough to eat through skin. Examples of bases include those in antacid tablets and drain cleaner. Bases in antacid tablets are weak enough to take for an upset stomach. Bases in drain cleaner are strong enough to cause serious burns.
What do mammals conserve heat with?	tendons or hair	fur or muscle	skin or bones	hair or fur	Mammals conserve heat with their hair or fur. It works like the layer of insulation in the walls of a house. It traps warm air next to the skin so it can’t escape into the environment. Like the squirrel in Figure below , most mammals can make their hair or fur stand up from the skin. This makes it a better insulator. Mammals also have a layer of insulating fat beneath their skin. Other vertebrates lack this layer of fat.
What is a mutation that changes all or much of a particular chromosome?	muscular mutation	kinetic mutation	biochemical mutation	chromosomal mutation	A mutation that changes all or a large part of a chromosome is called a chromosomal mutation. This type of mutation tends to be very serious. Sometimes chromosomes are missing or extra copies are present. An example is the mutation that causes Down syndrome. In this case, there is an extra copy of one of the chromosomes.
Defined as a difference in electric potential energy, a source of what is required in order to produce an electrical current?	magnetism	wattage	momentum	voltage	Current requires a source of voltage, which is a difference in electric potential energy. Sources of voltage include chemical cells and solar cells.
What hydrocarbons contain only single bonds between carbon atoms?	unsaturated hydrocarbons	caloric hydrocarbons	simple carbohydrates	saturated hydrocarbons	Saturated hydrocarbons are hydrocarbons that contain only single bonds between carbon atoms. As a result, each carbon atom is bonded to as many hydrogen atoms as possible.
What is a decrease in the magnitude of the membrane potential?	inflammation	digestion	ionization	depolarization
Water pollution occurs when chemicals, sewage, trash, or heat enter what?	natural resources	renewable resources	air resources	water resources	Water pollution occurs when chemicals, sewage, trash, or heat enter water resources. Water pollution is threatening the limited supply of clean, fresh water that human beings and other living things depend on.
Radioisotopes may vary greatly in their rate of decay, decaying faster if their nuclei are more what?	stable	mature	immature	unstable	Different radioisotopes may vary greatly in their rate of decay. The more unstable their nuclei are, the faster they decay.
Where can composite volcanoes most frequently be found?	astatine boundaries	divergent boundaries	transform boundaries	convergent boundaries	Composite volcanoes are common at convergent boundaries. Shield volcanoes are produced at divergent plate boundaries and intraplate.
The digestive, excretory, and reproductive systems of amphibians share a body cavity called what?	urethra	stoma	anus	cloaca	All amphibians have digestive, excretory, and reproductive systems. All three systems share a body cavity called the cloaca. Wastes enter the cloaca from the digestive and excretory systems, and gametes enter the cloaca from the reproductive system. An opening in the cloaca allows the wastes and gametes to leave the body.
Vertebrates are a subphylum of what phylum?	porifera	arthropoda	hydrozoa	chordata	Vertebrates are a subphylum of the phylum Chordata. Like all chordates, vertebrates have a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail. What other characteristics do vertebrates have? What traits set them apart from invertebrate chordates?.
What is the latin name for mercury?	spirogyra	trichina	stibium	hydrargyrum	In this image, you see small pools of elemental mercury. The Latin name for mercury is hydrargyrum, a compound word meaning “water-silver” (hydr- = water, -argyros = silver), since it is liquid like water but shiny like silver. Mercury is the only pure metal that exists as a liquid at room temperature.
The brain is said to contain gray matter, while what related structure contains white matter separated into columns?	orbital lobe	brain stem	amygdala	spinal cord	White Columns Just as the gray matter is separated into horns, the white matter of the spinal cord is separated into columns. Ascending tracts of nervous system fibers in these columns carry sensory information up to the brain, whereas descending tracts carry motor commands from the brain. Looking at the spinal cord longitudinally, the columns extend along its length as continuous bands of white matter. Between the two posterior horns of gray matter are the posterior columns. Between the two anterior horns, and bounded by the axons of motor neurons emerging from that gray matter area, are the anterior columns. The white matter on either side of the spinal cord, between the posterior horn and the axons of the anterior horn neurons, are the lateral columns. The posterior columns are composed of axons of ascending tracts. The anterior and lateral columns are composed of many different groups of axons of both ascending and descending tracts—the latter carrying motor commands down from the brain to the spinal cord to control output to the periphery.
What type of behavior occurs naturally in all animals of a given species?	reflex	learned	observational	innate	An innate behavior is any behavior that occurs naturally in all animals of a given species. An innate behavior is also called an instinct . The first time an animal performs an innate behavior, the animal does it well. The animal does not have to practice the behavior in order to get it right or become better at it. Innate behaviors are also predictable. All members of a species perform an innate behavior in the same way. From the examples described above, you can probably tell that innate behaviors usually involve important actions, like eating and caring for the young.
What orbits an atoms' nucleus?	isotopes	neutrally charged ions	positively charged protons	negatively charged electrons	An atom has negatively-charged electrons in orbit around its nucleus.
What are the three forms of water as found in nature?	solid , mixture , gas	balanced , liquid , gas	ice, vapor, sleet	solid, liquid, gas
What type of digestion is chewing an example of?	fluid	electromagnetic	gravity	mechanical
How many major massive extinctions have been since life began on earth?	one	three	four	five	Since life began on Earth, there have been at least five major massive extinctions.
What tool do scientist's use to show the evolutionary pathways and connections among organisms?	photogenetic tree	conceptual tree	superficial tree	phylogenetic tree	Phylogenetic Trees Scientists use a tool called a phylogenetic tree to show the evolutionary pathways and connections among organisms. A phylogenetic tree is a diagram used to reflect evolutionary relationships among organisms or groups of organisms. Scientists consider phylogenetic trees to be a hypothesis of the evolutionary past since one cannot go back to confirm the proposed relationships. In other words, a “tree of life” can be constructed to illustrate when different organisms evolved and to show the relationships among different organisms (Figure 20.2). Unlike a taxonomic classification diagram, a phylogenetic tree can be read like a map of evolutionary history. Many phylogenetic trees have a single lineage at the base representing a common ancestor. Scientists call such trees rooted, which means there is a single ancestral lineage (typically drawn from the bottom or left) to which all organisms represented in the diagram relate. Notice in the rooted phylogenetic tree that the three domains— Bacteria, Archaea, and Eukarya—diverge from a single point and branch off. The small branch that plants and animals (including humans) occupy in this diagram shows how recent and miniscule these groups are compared with other organisms. Unrooted trees don’t show a common ancestor but do show relationships among species.
What kind of bonds are there between carbon atoms in saturated fatty acids?	chemical	electrical	double	single	In saturated fatty acids, there are only single bonds between carbon atoms. As a result, the carbons are saturated with hydrogen atoms. Saturated fatty acids are found in fats. Fats are solid lipids that animals use to store energy.
In winter, water does what, becoming solid and causing hoses to rupture and engine blocks to crack?	fractures	crystallizes	shrinks	freeze	In the winter, the temperature often gets well below the freezing point of water. This condition can create problem in car radiators. If the water freezes, water hoses will break, the engine block can crack, and significant damage can be done to the car.
Unlike archaea and eukaryotes, bacteria have a cell wall made of what?	hydrogen	substrates	phospholipids	peptidoglycan	Unlike Archaea and eukaryotes, bacteria have a cell wall made of peptidoglycan, comprised of sugars and amino acids, and many have a polysaccharide capsule (Figure 3.5). The cell wall acts as an extra layer of protection, helps the cell maintain its shape, and prevents dehydration. The capsule enables the cell to attach to surfaces in its environment. Some prokaryotes have flagella, pili, or fimbriae. Flagella are used for locomotion, while most pili are used to exchange genetic material during a type of reproduction called conjugation.
What happens to the crust if the moving oceanic crust reaches a deep sea trench?	forms a continent	ocean volcano	it cleaves	sinks into mantle	In some places, the oceanic crust comes up to a continent. The moving crust pushes that continent away from the ridge axis as well. If the moving oceanic crust reaches a deep sea trench, the crust sinks into the mantle. The creation and destruction of oceanic crust is the reason that continents move. Seafloor spreading is the mechanism that Wegener was looking for!.
Polygenic traits are controlled by more than one of these?	genomes	phenotypes	chromosomes	genes	Some traits are controlled by more than one gene. They are called polygenic traits. Each gene for a polygenic trait may have two or more alleles. The genes may be on the same or different chromosomes. Polygenic traits may have many possible phenotypes. Skin color and adult height are examples of polygenic traits in humans. Think about all the variation in the heights of adults you know. Normal adults may range from less than 5 feet tall to more than 7 feet tall. There are people at every gradation of height in between these extremes.
What system plays a critical role in the regulation of vascular homeostasis?	renal system	endocrine system	circulatory system	nervous system	Neural Regulation The nervous system plays a critical role in the regulation of vascular homeostasis. The primary regulatory sites include the cardiovascular centers in the brain that control both cardiac and vascular functions. In addition, more generalized neural responses from the limbic system and the autonomic nervous system are factors.
How many nonpolar bonds does an oxygen molecule have?	3	5	7	2	An oxygen molecule has two nonpolar bonds. This is called a double bond. The two oxygen atoms attract equally the four shared electrons.
What type of disease occurs when the immune system fails to recognize the body's own molecules?	congenital	gastrointestinal	cardiac	autoimmune	Autoimmune diseases occur when the immune system fails to recognize the body’s own molecules as “self,” or belonging to the person. Instead, it attacks body cells as though they were dangerous pathogens. There are more than 80 known autoimmune diseases. Recall that regulatory T cells help regulate the immune system. When autoimmune disorders occur, these regulatory T cells fail in their function. This results in damage to various organs and tissues. The type of autoimmune disorder depends on the type of body tissue that is affected.
What organism is an important pioneer on cleared rock and soil surfaces, such as volcanic flows and burned forests?	pigment	cysts	algae	lichen
What hypothetical link between development of herbivores and plant defenses is observed in nature, for instance in seeds that are unsavory to animals?	natural selection	interconnection	abjection	coevolution	Animals and Plants: Herbivory Coevolution of flowering plants and insects is a hypothesis that has received much attention and support, especially because both angiosperms and insects diversified at about the same time in the middle Mesozoic. Many authors have attributed the diversity of plants and insects to pollination and herbivory, or consumption of plants by insects and other animals. This is believed to have been as much a driving force as pollination. Coevolution of herbivores and plant defenses is observed in nature. Unlike animals, most plants cannot outrun predators or use mimicry to hide from hungry animals. A sort of arms race exists between plants and herbivores. To “combat” herbivores, some plant seeds—such as acorn and unripened persimmon—are high in alkaloids and therefore unsavory to some animals. Other plants are protected by bark, although some animals developed specialized mouth pieces to tear and chew vegetal material. Spines and thorns (Figure 26.18) deter most animals, except for mammals with thick fur, and some birds have specialized beaks to get past such defenses.
The term salt can refer to essentially any of what compounds?	solvent	absorption	metallic	ionic	where the term salt can refer to essentially any ionic compound. An example would be the reaction between hydrochloric acid and potassium hydroxide:.
Where is the hypothalamus–pituitary complex located in the body?	stem of the brain	tribulus of the brain	subthalamic of the brain	diencephalon of the brain	17.3 The Pituitary Gland and Hypothalamus The hypothalamus–pituitary complex is located in the diencephalon of the brain. The hypothalamus and the pituitary gland are connected by a structure called the infundibulum, which contains vasculature and nerve axons. The pituitary gland is divided into two distinct structures with different embryonic origins. The posterior lobe houses the axon terminals of hypothalamic neurons. It stores and releases into the bloodstream two hypothalamic hormones: oxytocin and antidiuretic hormone (ADH). The anterior lobe is connected to the hypothalamus by vasculature in the infundibulum and produces and secretes six hormones. Their secretion is regulated, however, by releasing and inhibiting hormones from the hypothalamus. The six anterior pituitary hormones are: growth hormone (GH), thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), and prolactin (PRL).
Where is the guinea worm a serious problem?	ukraine	florida	russia	africa	Guinea worm is a serious problem in parts of Africa that is being eradicated. Learn what is being done to decrease the number of people suffering from this parasite at the video below:.
The reaction of calcium oxide with carbon dioxide forms what?	nitrogen	nitrogen carbonate	carbon monoxide	calcium carbonate	The way in which a reaction is written influences the value of the enthalpy change for the reaction. Many reactions are reversible, meaning that the product(s) of the reaction are capable of combining and reforming the reactant(s). If a reaction is written in the reverse direction, the sign of the changes. For example, we can write an equation for the reaction of calcium oxide with carbon dioxide to form calcium carbonate.
Cilia or flagella structures give protists what ability?	eating	reproduction	breathing	movement	An animal-like protist, or a protozoa. These protists have the ability to move, usually with some sort of cilia or flagella, and must obtain their energy from other sources. But obviously, they are much simpler than animals.
What is characterized by uncontrolled cell division of abnormal cells?	hepatitis	radiation	concussions	cancer	cell depletion, organ system failure, and impaired tissue injury responses. Telomerase reactivation in these mice caused extension of telomeres, reduced DNA damage, reversed neurodegeneration, and improved the function of the testes, spleen, and intestines. Thus, telomere reactivation may have potential for treating age-related diseases in humans. Cancer is characterized by uncontrolled cell division of abnormal cells. The cells accumulate mutations, proliferate uncontrollably, and can migrate to different parts of the body through a process called metastasis. Scientists have observed that cancerous cells have considerably shortened telomeres and that telomerase is active in these cells. Interestingly, only after the telomeres were shortened in the cancer cells did the telomerase become active. If the action of telomerase in these cells can be inhibited by drugs during cancer therapy, then the cancerous cells could potentially be stopped from further division.
Our global ecological footprint depends on resource use per person and what population factor?	population decrease	population fluctuation	population sample	population density
What do all sound waves begin with?	enclosing matter	oscillating matter	talking matter	vibrating matter	All sound waves begin with vibrating matter. The vibrations generate longitudinal waves that travel through matter in all directions.
Animal starch, called glycogen, is stored in the liver and where else?	hands	kidneys	nerves	muscles	Note the Pattern Because carbohydrates have a carbonyl functional group and several hydroxyl groups, they can undergo a variety of reactions. Two familiar polysaccharides are starch and cellulose, which both hydrolyze to produce thousands of glucose units. They differ only in the connection between glucose units and the amount of branching in the molecule (Figure 24.22 "The Polysaccharides Starch and Cellulose"). Starches can be coiled or branched and are hydrolyzed by the enzymes in our saliva and pancreatic juices. Animal starch, called glycogen, is stored in the liver and muscles. It consists of branched glucose units linked by bonds Saylor URL: http://www. saylor. org/books.
Kepler's laws relate to the motion of what?	the sun	continents	oceans	planets	The system is isolated from other masses. This allows us to neglect any small effects due to outside masses. The conditions are satisfied, to good approximation, by Earth’s satellites (including the Moon), by objects orbiting the Sun, and by the satellites of other planets. Historically, planets were studied first, and there is a classical set of three laws, called Kepler’s laws of planetary motion, that describe the orbits of all bodies satisfying the two previous conditions (not just planets in our solar system). These descriptive laws are named for the German astronomer Johannes Kepler (1571–1630), who devised them after careful study (over some 20 years) of a large amount of meticulously recorded observations of planetary motion done by Tycho Brahe (1546–1601). Such careful collection and detailed recording of methods and data are hallmarks of good science. Data constitute the evidence from which new interpretations and meanings can be constructed.
Colloids are used industrially as what?	solutions	organisms	impurities	catalysts	Suspensions and colloids are two common types of mixtures whose properties are in many ways intermediate between those of true solutions and heterogeneous mixtures. Asuspension is a heterogeneous mixture of particles with diameters of about 1 µm (1000 nm) that are distributed throughout a second phase. Common suspensions include paint, blood, and hot chocolate, which are solid particles in a liquid, and aerosol sprays, which are liquid particles in a gas. If the suspension is allowed to stand, the two phases will separate, which is why paints must be thoroughly stirred or shaken before use. A colloid is also a heterogeneous mixture, but the particles of a colloid are typically smaller than those of a suspension, generally in the range of 2 to about 500 nm in diameter. Colloids include fog and clouds (liquid particles in a gas), milk (solid particles in a liquid), and butter (solid particles in a solid). Other colloids are used industrially as catalysts. Unlike in a suspension, the particles in a colloid do not separate into two phases on standing. The only combination of substances that cannot produce a suspension or a colloid is a mixture of two gases because their particles are so small that they always form true solutions. The properties of suspensions, colloids, and solutions are summarized in Table 13.9 "Properties of Liquid Solutions, Colloids, and Suspensions".
What is defined as the temperature plus precipitation of an area over a long period of time?	weather	conditions	environment	climate	Climate is the temperature plus precipitation of an area. Not just today, but over a long period of time. Climate affects chemical weathering. Chemical weathering increases as:.
What manages the material and energy resources of the cell?	nucleus	cell wall	respiration	metabolism
What is the midpiece of sperm packed with?	urine	protein	glucose	mitochondria	The midpiece of the sperm is packed with mitochondria. Mitochondria are organelles in cells that produce energy. Sperm use the energy in the midpiece to move.
Dry soils are relatively unproductive because plants need a sufficient quantity of liquid water to carry out what process?	flowering	contraction	shrinkage	photosynthesis
The vitamins and minerals contained in all of the food we consume are important for all of our organ systems. however, there are certain nutrients that affect this?	chain health	mental health	abnormal health	bone health	Nutrition and Bone Tissue The vitamins and minerals contained in all of the food we consume are important for all of our organ systems. However, there are certain nutrients that affect bone health.
What type of plants supplement their mineral nutrition by digesting animals?	herbivorous	perennials	annuals	carnivorous
Daughter cells divide by what?	nucleus	electrolysis	mitosis	meiosis	The daughter cells then start to divide by meiosis . But they only go through the first of the two cell divisions of meiosis at that time. They go through the second stage of cell division after the female goes through puberty.
Phytochromes regulate many plant responses to what?	oxygen	heat	gravity	light
Carbon dioxide molecules consist of a central carbon atom bonded to how many oxygen atoms?	three	one	four	two	Carbon dioxide molecules consist of a central carbon atom bonded to 2 oxygen atoms.
Survivorship curves show the distribution of individuals in a population according to what metric?	birth rate	weight	height	age	Figure 19.4 Survivorship curves show the distribution of individuals in a population according to age. Humans and most mammals have a Type I survivorship curve, because death primarily occurs in the older years. Birds have a Type II survivorship curve, as death at any age is equally probable. Trees have a Type III survivorship curve because very few survive the younger years, but after a certain age, individuals are much more likely to survive.
Electrons are not shared equally between the two atoms in which type of covalent bonds?	solar	wide	narrow	polar	In polar covalent bonds, electrons are not shared equally between the two atoms, so one atom is slightly negative in charge and one is slightly positive in charge. In nonpolar covalent bonds, electrons are shared equally so the atoms remain neutral in charge.
What is above each leaf scar?	stipule scar	chambered pitch	lenticel	an axillary bud
Ultimately, the fluid that is lost from the blood vessels is returned through what system?	urinary	symptomatic	venous	lymphatic	None of your blood vessels are leaking this badly, or you'd be in the hospital! But your blood vessels do leak a little bit. Water and solutes pass out of the blood vessels and help form the fluid that bathes your body's tissues. Ultimately the fluid that is lost from the blood vessels is returned through the lymphatic system.
What type energy sources emit fewer or no greenhouse gases?	fossil	gas	animal	renewable	New technologies can be developed. Renewable energy sources emit fewer or no greenhouse gases. These sources are discussed in the chapter Natural Resources .
Stars spend most of their lives on the main sequence, fusing hydrogen into what?	nitrogen	neon	carbon	helium	Stars spend most of their lives on the main sequence, fusing hydrogen into helium.
What is a measure of how hot or cold the air is?	relativity	precipitation	variation	temperature
Where are more of an insect's internal organs kept?	the chest cavity	the head	the thorax	the abdomen	An insect’s abdomen contains most of the internal organs. Like other arthropods, insects have a complete digestive system. They also have an open circulatory system and central nervous system. Like other terrestrial arthropods, they have trachea for breathing air and Malphigian tubules for excretion.
What is the measure of kinetic energy of the particles in matter?	friction	energy	precipitation	temperature	Temperature is a measure of the average kinetic energy of the particles in matter. In everyday usage, temperature indicates a measure of how hot or cold an object is. Temperature is an important parameter in chemistry. When a substance changes from solid to liquid, it is because there was an increase in the temperature of the material. Chemical reactions usually proceed faster if the temperature is increased. Many unstable materials (such as enzymes) will be viable longer at lower temperatures.
What is the name for the tiny air sacs at the end of bronchioles?	ganglion	gills	vacuoles	alveoli	Finally, air passes from the bronchi into smaller passages called bronchioles. The bronchioles end in tiny air sacs called alveoli.
What is the source of most of the energy used?	the Moon	the Earth	fossil fuels	the sun	The Sun produces far more energy than humans can use. The Sun is also the source of most of the energy we use. Fossil fuels and wind energy, for example, originate with the Sun. So why don't we get all our energy from the Sun? For one reason, it's not always practical.
What flows across the membrane resulting in changes in the membrane potential?	neutrons	electrons	acids	ions
The standard reduction potential can be determined by subtracting the standard reduction potential for the reaction occurring at the anode from the standard reduction potential for the reaction occurring at this?	electrode	Spinner	plasma	cathode	The standard reduction potential can be determined by subtracting the standard reduction potential for the reaction occurring at the anode from the standard reduction potential for the reaction occurring at the cathode. The minus sign is necessary because oxidation is the reverse of reduction. E°cell = E°cathode − E°anode +0.34 V = E° 2+ − E°H + /H = E° 2+ − 0 = E° Cu.
What are proteins made up of?	atoms acids	lewis acids	detected acids	amino acids	Proteins are formed when hundreds or even thousands of amino acids form amide bonds to make polymers. Proteins play a crucial role in living organisms. A carbohydrate is a compound that has the general formula Cn(H2O)n. Many carbohydrates are relatively small molecules, such as glucose:.
What proteins synthesized in cells act as catalysts?	byproducts	hormones	virophages	enzymes	Chemical reactions constantly occur inside the cells of living things. However, under the conditions inside cells, most biochemical reactions would occur too slowly to maintain life. That’s where enzymes come in. Enzymes are catalysts in living things. Like other catalysts, they speed up chemical reactions. Enzymes are proteins that are synthesized in the cells that need them, based on instructions encoded in the cells’ DNA.
What element is the sun mostly made up of?	helium	manganese	mercury	hydrogen	The Sun is mostly hydrogen with smaller amounts of helium. The material is in the form of plasma.
What shape is the gametophyte in ferns?	diamond	circular	rectangular	heart-shaped	In ferns, the sporophyte is dominant and produces spores that germinate into a heart-shaped gametophyte.
What makes sunsets appear red?	floral scattering	wavelength scattering	reflection scattering	rayleigh scattering	Beautiful sunsets are another manifestation of Rayleigh scattering that occurs when light travels long distances through the atmosphere. The blue light and some green is scattered away, making the sun appear red.
Skeletal and muscular are examples of what type of system?	shell system	internal system	interior system	organ system	Organs are organized into organ systems such as the skeletal and muscular systems.
What is the process where light bounces back from surfaces that it cannot pass through?	absorbtion	diffraction	direction	reflection	Reflection of light occurs when light bounces back from a surface that it cannot pass through. If the surface is very smooth, the reflected light forms an image.
What are butterflies and bees an example of?	parasites	spores	species	pollinators
What are clouds that form on the ground called?	canopy	haze	smoke	fog	Clouds form when air in the atmosphere reaches the dew point. Clouds may form anywhere in the troposphere. Clouds that form on the ground are called fog .
What is formed when atoms of different elements bond together?	duality compound	univalent compound	phenotype compound	covalent compound	The two atoms that are held together in a covalent bond may be atoms of the same element or different elements. When atoms of different elements bond together, it forms a covalent compound.
Where a cell resides, how it appears, and what it does define its what?	life cycle	minute race	slowing rate	development fate

What happens to the temperature of a system during phase change?

decreases

increases

fluctuates rapidly

remains constant

This plot of temperature shows what happens to a 75 g sample of ice initially at 1 atm and −23°C as heat is added at a constant rate: A–B: heating solid ice; B–C: melting ice; C–D: heating liquid water; D– E: vaporizing water; E–F: heating steam. Thus the temperature of a system does not change during a phase change. In this example, as long as even a tiny amount of ice is present, the temperature of the system remains at 0°C during the melting process, and as long as even a small amount of liquid water is present, the temperature of the system remains at 100°C during the boiling process. The rate at which heat is added does not affect the temperature of the ice/water or water/steam mixture because the added heat is being used exclusively to overcome the attractive forces that hold the more condensed phase together. Many cooks think that food will cook faster if the heat is turned up higher so that the water boils more rapidly. Instead, the pot of water will boil to dryness sooner, but the temperature of the water does not depend on how vigorously it boils.

What is the major cause of outdoor air pollution?

manufacturing industry

electric lines

agricultural equipment

burning fossil fuels

The major cause of outdoor air pollution is the burning of fossil fuels. Fossil fuels are burned in power plants, factories, motor vehicles, and home heating systems. Ranching and using chemicals such as fertilizers also cause outdoor air pollution. Erosion of soil in farm fields, mining activities, and construction sites adds dust particles to the air as well. Some specific outdoor air pollutants are described in Table below .

Why does a metal spoon heat up quickly when placed in a hot drink?

convection

insulation

high specific heat

low specific heat

The Table below compares the specific heat of four different substances. Metals such as iron have low specific heat. It doesn’t take much energy to raise their temperature. That’s why a metal spoon heats up quickly when placed in a cup of hot coffee. Sand also has a relatively low specific heat. Water, on the other hand, has a very high specific heat. It takes a lot more energy to increase the temperature of water than sand. This explains why the sand on a beach gets hot while the water stays cool. Differences in the specific heat of water and land even affect climate. To learn how, watch the video at this URL: http://www. youtube. com/watch?v=dkBStF2Rnu4.

What does the megaspore mother cell produce after meiosis division?

two haploid megaspores

four diploid megaspores

two diploid megapores

four haploid megaspores

Watch this video (http://openstaxcollege. org/l/pollen_release) to see a cedar releasing its pollen in the wind. Female Gametophyte The female cone also has a central axis on which bracts known as megasporophylls (Figure 32.10) are present. In the female cone, megaspore mother cells are present in the megasporangium. The megaspore mother cell divides by meiosis to produce four haploid megaspores. One of the megaspores divides to form the multicellular female gametophyte, while the others divide to form the rest of the structure. The female gametophyte is contained within a structure called the archegonium.

Synaptic connections can change over time depending on what?

age

weight

diet

activity level

What is the body of a roundworm covered with?

slime

thick scales

thin epidermis

tough cuticle

Roundworms have a pseudocoelom and hydrostatic skeleton. Their body is covered with tough cuticle.

The end of the phospholipid molecule that is polar and attracts water is called what?

magnetic

cytosolic

hydrophobic

hydrophilic

Figure below shows how phospholipid molecules are arranged in a cell membrane. One end (the head) of each phospholipid molecule is polar and attracts water. This end is called hydrophilic ("water loving"). The other end (the tail) is nonpolar and repels water. This end is called hydrophobic ("water hating"). The nonpolar tails are on the inside of the membrane. The polar heads are on the outside of the membrane. These differences in polarity allow some molecules to pass through the membrane while keeping others out. You can see how this works in the video at the URL below.

What is known as the universal solvent?

vinegar

oil

air

water

The ability of a solute to dissolve in a particular solvent is called solubility . Many chemical substances are soluble in water. In fact, so many substances are soluble in water that water is called the universal solvent. Water is a strongly polar solvent, and polar solvents are better at dissolving polar solutes. Many organic compounds and other important biochemicals are polar, so they dissolve well in water. On the other hand, strongly polar solvents like water cannot dissolve strongly nonpolar solutes like oil. Did you ever try to mix oil and water? Even after being well shaken, the two substances quickly separate into distinct layers.

Any organism that causes disease is called what?

a microbe

a parasite

a virus

a pathogen

You have ten times as many bacterial cells as human cells in your body. Luckily for you, most of these bacteria are harmless. However, some of them can cause disease. Any organism that causes disease is called a pathogen . Diseases caused by bacterial pathogens include food poisoning, strep throat, and Lyme disease.

Electric generators change kinetic energy to what type of energy?

intrinsic

thermal

light

electrical

Sources of voltage include electric generators and cells. Electric generators change kinetic energy to electrical energy. Chemical cells change chemical energy to electrical energy, and solar cells change solar energy to electrical energy.

Brown algae are important commodities for what?

parasites

reptiles

fish

humans

What does the large central vacuole do?

heat water

use water

create glucose

store water

First, plant cells have a large central vacuole that holds a mixture of water, nutrients, and wastes. A plant cell's vacuole can make up 90% of the cell’s volume. The large central vacuole essentially stores water. In animal cells, vacuoles are much smaller.

What is the ratio of solutes in a solution to a volume of solvent in a solution known as?

molality

equilibrium

molarity

osmolality

Regulation of Water Intake Osmolality is the ratio of solutes in a solution to a volume of solvent in a solution. Plasma osmolality is thus the ratio of solutes to water in blood plasma. A person’s plasma osmolality value reflects his or her state of hydration. A healthy body maintains plasma osmolality within a narrow range, by employing several mechanisms that regulate both water intake and output. Drinking water is considered voluntary. So how is water intake regulated by the body? Consider someone who is experiencing dehydration, a net loss of water that results in insufficient water in blood and other tissues. The water that leaves the body, as exhaled air, sweat, or urine, is ultimately extracted from blood plasma. As the blood becomes more concentrated, the thirst response—a sequence of physiological processes—is triggered (Figure 26.10). Osmoreceptors are sensory receptors in the thirst center in the hypothalamus that monitor the concentration of solutes (osmolality) of the blood. If blood osmolality increases above its ideal value, the hypothalamus transmits signals that result in a conscious awareness of thirst. The person should (and normally does) respond by drinking water. The hypothalamus of a dehydrated person also releases antidiuretic hormone (ADH) through the posterior pituitary gland. ADH signals the kidneys to recover water from urine, effectively diluting the blood plasma. To conserve water, the hypothalamus of a dehydrated person also sends signals via the sympathetic nervous system to the salivary glands in the mouth. The signals result in a decrease in watery, serous output (and an increase in stickier, thicker mucus output). These changes in secretions result in a “dry mouth” and the sensation of thirst.

What type of rock contains concentrations of valuable minerals?

metamorphic

sedimentary

igneous

ores

A mineral deposit that contains enough minerals to be mined for profit is called an ore . Ores are rocks that contain concentrations of valuable minerals. The bauxite shown in the Figure below is a rock that contains minerals that are used to make aluminum.

How many digits do primates have on each extremity?

three

ten

four

five

Primates have five digits (fingers or toes) on each extremity. Unlike the hooves of horses or the paddles of whales, the digits of primates are relatively unspecialized. Therefore, they can be used to do a variety of tasks, including grasping branches and holding tools.

Dna is normally found within what region of a cell?

Golgi apparatus

genome sequence

mitochondria

nucleus

the nucleus. The nucleus contains one or more nucleoli, which serve as sites for ribosome synthesis. The nucleus houses the genetic material of the cell: DNA. DNA is normally found as a loosely contained structure called chromatin within the nucleus, where it is wound up and associated with a variety of histone proteins. When a cell is about to divide, the chromatin coils tightly and condenses to form chromosomes. There is a pool of cells constantly dividing within your body. The result is billions of new cells being created each day. Before any cell is ready to divide, it must replicate its DNA so that each new daughter cell will receive an exact copy of the organism’s genome. A variety of enzymes are enlisted during DNA replication. These enzymes unwind the DNA molecule, separate the two strands, and assist with the building of complementary strands along each parent strand. The original DNA strands serve as templates from which the nucleotide sequence of the new strands are determined and synthesized. When replication is completed, two identical DNA molecules exist. Each one contains one original strand and one newly synthesized complementary strand.

Water and carbon dioxide molecules are reactants in what plant process?

glycolysis

digestion

breathing

photosynthesis

Water and carbon dioxide molecules are reactants in the process of photosynthesis. Does this mean they are “food” for plants, algae, and blue-green bacteria? Use the definition of “food” to answer this question.

Gene therapy is a type of what kind of engineering?

chemical engineering

mechanical engineering

electrical engineering

genetic engineering

Biotechnology in Medicine and Agriculture It is easy to see how biotechnology can be used for medicinal purposes. Knowledge of the genetic makeup of our species, the genetic basis of heritable diseases, and the invention of technology to manipulate and fix mutant genes provides methods to treat the disease. Biotechnology in agriculture can enhance resistance to disease, pest, and environmental stress, and improve both crop yield and quality. Genetic Diagnosis and Gene Therapy The process of testing for suspected genetic defects before administering treatment is called genetic diagnosis by genetic testing. Depending on the inheritance patterns of a disease-causing gene, family members are advised to undergo genetic testing. For example, women diagnosed with breast cancer are usually advised to have a biopsy so that the medical team can determine the genetic basis of cancer development. Treatment plans are based on the findings of genetic tests that determine the type of cancer. If the cancer is caused by inherited gene mutations, other female relatives are also advised to undergo genetic testing and periodic screening for breast cancer. Genetic testing is also offered for fetuses (or embryos with in vitro fertilization) to determine the presence or absence of disease-causing genes in families with specific debilitating diseases. Gene therapy is a genetic engineering technique used to cure disease. In its simplest form, it involves the introduction of a good gene at a random location in the genome to aid the cure of a disease that is caused by a mutated gene. The good gene is usually introduced into diseased cells as part of a vector transmitted by a virus that can infect the host cell and deliver the foreign DNA (Figure 17.9). More advanced forms of gene therapy try to correct the mutation at the original site in the genome, such as is the case with treatment of severe combined immunodeficiency (SCID).

What is mass number?

the total number of protons and chondrichthyes in a nucleus

to total number of electrons and neutrons in a nucleus

to total number of protons and electrons in a nucleus

the total number of protons and neutrons in a nucleus

All oxygen atoms have eight protons, and most have eight neutrons as well. What is the mass number of an oxygen isotope that has nine neutrons? What is the name of this isotope?.

What rises through solid rocks where conditions are right?

nitrogen

crystals

water

magma

Lithospheric plates do a lot of moving on Earth's surface. Slabs of lithosphere smash into each other. They move sideways past each other along faults. Where conditions are right, magma rises through solid rock. It's no wonder that rocks experience stress! Rocks respond differently to different types of stress and under different conditions.

What is the connecting piece of a sperm packed with?

Gelatin

glucose

protein

mitochondria

The connecting piece of the sperm is packed with mitochondria. Mitochondria are organelles in cells that produce energy. Sperm use the energy to move.

What is a diagram that shows a single way that energy flows throughout an ecosystem?

water cycle

fuel chain

dependent chain

food chain

A food chain is a simple diagram that shows one way energy flows through an ecosystem. Pictured below is an example of a food chain ( Figure below ). Producers form the base of all food chains. The consumers that eat producers are called primary consumers. The consumers that eat primary consumers are secondary consumers. This chain can continue to multiple levels.

Different colors of light differ in terms of which important attribute?

frequencies

lenses

prisms

wavelengths

Nobody really has such colorful eyes! The colors were added digitally after the photo was taken. They represent all the different colors of light. Light is a form of energy that travels in waves. Light of different colors has different wavelengths.

Ion drives have low thrust but high what?

tolerance

power

acceleration

efficiency

Ion drives have low thrust but high efficiency. They have already been used on several space missions, including NASA’s Deep Space 1spacecraft and Japan’sHayabusa asteroid sampling probe. Source: Photo courtesy of NASA,http://commons. wikimedia. org/wiki/File:Ion_Engine_Test_Firing_-_GPN2000-000482.

For most waves, energy is proportional to what, a term that describes the height of the wave?

wave threshold

wave frequency

wave volume

wave amplitude

Light also behaves like a package of energy. It turns out that for light, the energy of the “package” of energy is proportional to its frequency. (For most waves, energy is proportional to wave amplitude, or the height of the wave. ) The mathematical equation that relates the energy (E) of light to its frequency is.

What are the primary causes of bone fractures?

step impact or bending

overuse

spiral impact or bending

sideways impact or bending

Each ionic compound has its own unique name that comes from the names of the ions.

Water is polar and has electrically charged ends, so it is attracted to the oppositely charged end of a phospholipid molecule, which is described by what term meaning "water-loving"?

cytosolic

aqueous

hydrophobic

hydrophilic

One end of each phospholipid molecule is polar, so it has a partial electric charge. Water is also polar and has electrically charged ends, so it is attracted to the oppositely charged end of a phospholipid molecule. This end of the phospholipid molecule is described as hydrophilic, which means “water loving. ”.

What is produced when a base is dissolved in water?

ingredient ions

alkaline ions

synthesis ions

hydroxide ions

Acids are ionic compounds that produce positively charged hydrogen ions (H + ) when dissolved in water. Acids taste sour and react with metals. Bases are ionic compounds that produce negatively charged hydroxide ions (OH - ) when dissolved in water. Bases taste bitter and do not react with metals. Examples of acids are vinegar and battery acid. The acid in vinegar is weak enough to safely eat on a salad. The acid in a car battery is strong enough to eat through skin. Examples of bases include those in antacid tablets and drain cleaner. Bases in antacid tablets are weak enough to take for an upset stomach. Bases in drain cleaner are strong enough to cause serious burns.

What do mammals conserve heat with?

tendons or hair

fur or muscle

skin or bones

hair or fur

Mammals conserve heat with their hair or fur. It works like the layer of insulation in the walls of a house. It traps warm air next to the skin so it can’t escape into the environment. Like the squirrel in Figure below , most mammals can make their hair or fur stand up from the skin. This makes it a better insulator. Mammals also have a layer of insulating fat beneath their skin. Other vertebrates lack this layer of fat.

What is a mutation that changes all or much of a particular chromosome?

muscular mutation

kinetic mutation

biochemical mutation

chromosomal mutation

A mutation that changes all or a large part of a chromosome is called a chromosomal mutation. This type of mutation tends to be very serious. Sometimes chromosomes are missing or extra copies are present. An example is the mutation that causes Down syndrome. In this case, there is an extra copy of one of the chromosomes.

Defined as a difference in electric potential energy, a source of what is required in order to produce an electrical current?

magnetism

wattage

momentum

voltage

Current requires a source of voltage, which is a difference in electric potential energy. Sources of voltage include chemical cells and solar cells.

What hydrocarbons contain only single bonds between carbon atoms?

unsaturated hydrocarbons

caloric hydrocarbons

simple carbohydrates

saturated hydrocarbons

Saturated hydrocarbons are hydrocarbons that contain only single bonds between carbon atoms. As a result, each carbon atom is bonded to as many hydrogen atoms as possible.

What is a decrease in the magnitude of the membrane potential?

inflammation

digestion

ionization

depolarization

Water pollution occurs when chemicals, sewage, trash, or heat enter what?

natural resources

renewable resources

air resources

water resources

Water pollution occurs when chemicals, sewage, trash, or heat enter water resources. Water pollution is threatening the limited supply of clean, fresh water that human beings and other living things depend on.

Radioisotopes may vary greatly in their rate of decay, decaying faster if their nuclei are more what?

stable

mature

immature

unstable

Different radioisotopes may vary greatly in their rate of decay. The more unstable their nuclei are, the faster they decay.

Where can composite volcanoes most frequently be found?

astatine boundaries

divergent boundaries

transform boundaries

convergent boundaries

Composite volcanoes are common at convergent boundaries. Shield volcanoes are produced at divergent plate boundaries and intraplate.

The digestive, excretory, and reproductive systems of amphibians share a body cavity called what?

urethra

stoma

anus

cloaca

All amphibians have digestive, excretory, and reproductive systems. All three systems share a body cavity called the cloaca. Wastes enter the cloaca from the digestive and excretory systems, and gametes enter the cloaca from the reproductive system. An opening in the cloaca allows the wastes and gametes to leave the body.

Vertebrates are a subphylum of what phylum?

porifera

arthropoda

hydrozoa

chordata

Vertebrates are a subphylum of the phylum Chordata. Like all chordates, vertebrates have a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail. What other characteristics do vertebrates have? What traits set them apart from invertebrate chordates?.

What is the latin name for mercury?

spirogyra

trichina

stibium

hydrargyrum

In this image, you see small pools of elemental mercury. The Latin name for mercury is hydrargyrum, a compound word meaning “water-silver” (hydr- = water, -argyros = silver), since it is liquid like water but shiny like silver. Mercury is the only pure metal that exists as a liquid at room temperature.

The brain is said to contain gray matter, while what related structure contains white matter separated into columns?

orbital lobe

brain stem

amygdala

spinal cord

White Columns Just as the gray matter is separated into horns, the white matter of the spinal cord is separated into columns. Ascending tracts of nervous system fibers in these columns carry sensory information up to the brain, whereas descending tracts carry motor commands from the brain. Looking at the spinal cord longitudinally, the columns extend along its length as continuous bands of white matter. Between the two posterior horns of gray matter are the posterior columns. Between the two anterior horns, and bounded by the axons of motor neurons emerging from that gray matter area, are the anterior columns. The white matter on either side of the spinal cord, between the posterior horn and the axons of the anterior horn neurons, are the lateral columns. The posterior columns are composed of axons of ascending tracts. The anterior and lateral columns are composed of many different groups of axons of both ascending and descending tracts—the latter carrying motor commands down from the brain to the spinal cord to control output to the periphery.

What type of behavior occurs naturally in all animals of a given species?

reflex

learned

observational

innate

An innate behavior is any behavior that occurs naturally in all animals of a given species. An innate behavior is also called an instinct . The first time an animal performs an innate behavior, the animal does it well. The animal does not have to practice the behavior in order to get it right or become better at it. Innate behaviors are also predictable. All members of a species perform an innate behavior in the same way. From the examples described above, you can probably tell that innate behaviors usually involve important actions, like eating and caring for the young.

What orbits an atoms' nucleus?

isotopes

neutrally charged ions

positively charged protons

negatively charged electrons

An atom has negatively-charged electrons in orbit around its nucleus.

What are the three forms of water as found in nature?

solid , mixture , gas

balanced , liquid , gas

ice, vapor, sleet

solid, liquid, gas

What type of digestion is chewing an example of?

fluid

electromagnetic

gravity

mechanical

How many major massive extinctions have been since life began on earth?

one

three

four

five

Since life began on Earth, there have been at least five major massive extinctions.

What tool do scientist's use to show the evolutionary pathways and connections among organisms?

photogenetic tree

conceptual tree

superficial tree

phylogenetic tree

Phylogenetic Trees Scientists use a tool called a phylogenetic tree to show the evolutionary pathways and connections among organisms. A phylogenetic tree is a diagram used to reflect evolutionary relationships among organisms or groups of organisms. Scientists consider phylogenetic trees to be a hypothesis of the evolutionary past since one cannot go back to confirm the proposed relationships. In other words, a “tree of life” can be constructed to illustrate when different organisms evolved and to show the relationships among different organisms (Figure 20.2). Unlike a taxonomic classification diagram, a phylogenetic tree can be read like a map of evolutionary history. Many phylogenetic trees have a single lineage at the base representing a common ancestor. Scientists call such trees rooted, which means there is a single ancestral lineage (typically drawn from the bottom or left) to which all organisms represented in the diagram relate. Notice in the rooted phylogenetic tree that the three domains— Bacteria, Archaea, and Eukarya—diverge from a single point and branch off. The small branch that plants and animals (including humans) occupy in this diagram shows how recent and miniscule these groups are compared with other organisms. Unrooted trees don’t show a common ancestor but do show relationships among species.

What kind of bonds are there between carbon atoms in saturated fatty acids?

chemical

electrical

double

single

In saturated fatty acids, there are only single bonds between carbon atoms. As a result, the carbons are saturated with hydrogen atoms. Saturated fatty acids are found in fats. Fats are solid lipids that animals use to store energy.

In winter, water does what, becoming solid and causing hoses to rupture and engine blocks to crack?

fractures

crystallizes

shrinks

freeze

In the winter, the temperature often gets well below the freezing point of water. This condition can create problem in car radiators. If the water freezes, water hoses will break, the engine block can crack, and significant damage can be done to the car.

Unlike archaea and eukaryotes, bacteria have a cell wall made of what?

hydrogen

substrates

phospholipids

peptidoglycan

Unlike Archaea and eukaryotes, bacteria have a cell wall made of peptidoglycan, comprised of sugars and amino acids, and many have a polysaccharide capsule (Figure 3.5). The cell wall acts as an extra layer of protection, helps the cell maintain its shape, and prevents dehydration. The capsule enables the cell to attach to surfaces in its environment. Some prokaryotes have flagella, pili, or fimbriae. Flagella are used for locomotion, while most pili are used to exchange genetic material during a type of reproduction called conjugation.

What happens to the crust if the moving oceanic crust reaches a deep sea trench?

forms a continent

ocean volcano

it cleaves

sinks into mantle

In some places, the oceanic crust comes up to a continent. The moving crust pushes that continent away from the ridge axis as well. If the moving oceanic crust reaches a deep sea trench, the crust sinks into the mantle. The creation and destruction of oceanic crust is the reason that continents move. Seafloor spreading is the mechanism that Wegener was looking for!.

Polygenic traits are controlled by more than one of these?

genomes

phenotypes

chromosomes

genes

Some traits are controlled by more than one gene. They are called polygenic traits. Each gene for a polygenic trait may have two or more alleles. The genes may be on the same or different chromosomes. Polygenic traits may have many possible phenotypes. Skin color and adult height are examples of polygenic traits in humans. Think about all the variation in the heights of adults you know. Normal adults may range from less than 5 feet tall to more than 7 feet tall. There are people at every gradation of height in between these extremes.

What system plays a critical role in the regulation of vascular homeostasis?

renal system

endocrine system

circulatory system

nervous system

Neural Regulation The nervous system plays a critical role in the regulation of vascular homeostasis. The primary regulatory sites include the cardiovascular centers in the brain that control both cardiac and vascular functions. In addition, more generalized neural responses from the limbic system and the autonomic nervous system are factors.

How many nonpolar bonds does an oxygen molecule have?

3

5

7

2

An oxygen molecule has two nonpolar bonds. This is called a double bond. The two oxygen atoms attract equally the four shared electrons.

What type of disease occurs when the immune system fails to recognize the body's own molecules?

congenital

gastrointestinal

cardiac

autoimmune

Autoimmune diseases occur when the immune system fails to recognize the body’s own molecules as “self,” or belonging to the person. Instead, it attacks body cells as though they were dangerous pathogens. There are more than 80 known autoimmune diseases. Recall that regulatory T cells help regulate the immune system. When autoimmune disorders occur, these regulatory T cells fail in their function. This results in damage to various organs and tissues. The type of autoimmune disorder depends on the type of body tissue that is affected.

What organism is an important pioneer on cleared rock and soil surfaces, such as volcanic flows and burned forests?

pigment

cysts

algae

lichen

What hypothetical link between development of herbivores and plant defenses is observed in nature, for instance in seeds that are unsavory to animals?

natural selection

interconnection

abjection

coevolution

Animals and Plants: Herbivory Coevolution of flowering plants and insects is a hypothesis that has received much attention and support, especially because both angiosperms and insects diversified at about the same time in the middle Mesozoic. Many authors have attributed the diversity of plants and insects to pollination and herbivory, or consumption of plants by insects and other animals. This is believed to have been as much a driving force as pollination. Coevolution of herbivores and plant defenses is observed in nature. Unlike animals, most plants cannot outrun predators or use mimicry to hide from hungry animals. A sort of arms race exists between plants and herbivores. To “combat” herbivores, some plant seeds—such as acorn and unripened persimmon—are high in alkaloids and therefore unsavory to some animals. Other plants are protected by bark, although some animals developed specialized mouth pieces to tear and chew vegetal material. Spines and thorns (Figure 26.18) deter most animals, except for mammals with thick fur, and some birds have specialized beaks to get past such defenses.

The term salt can refer to essentially any of what compounds?

solvent

absorption

metallic

ionic

where the term salt can refer to essentially any ionic compound. An example would be the reaction between hydrochloric acid and potassium hydroxide:.

Where is the hypothalamus–pituitary complex located in the body?

stem of the brain

tribulus of the brain

subthalamic of the brain

diencephalon of the brain

17.3 The Pituitary Gland and Hypothalamus The hypothalamus–pituitary complex is located in the diencephalon of the brain. The hypothalamus and the pituitary gland are connected by a structure called the infundibulum, which contains vasculature and nerve axons. The pituitary gland is divided into two distinct structures with different embryonic origins. The posterior lobe houses the axon terminals of hypothalamic neurons. It stores and releases into the bloodstream two hypothalamic hormones: oxytocin and antidiuretic hormone (ADH). The anterior lobe is connected to the hypothalamus by vasculature in the infundibulum and produces and secretes six hormones. Their secretion is regulated, however, by releasing and inhibiting hormones from the hypothalamus. The six anterior pituitary hormones are: growth hormone (GH), thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), and prolactin (PRL).

Where is the guinea worm a serious problem?

ukraine

florida

russia

africa

Guinea worm is a serious problem in parts of Africa that is being eradicated. Learn what is being done to decrease the number of people suffering from this parasite at the video below:.

The reaction of calcium oxide with carbon dioxide forms what?

nitrogen

nitrogen carbonate

carbon monoxide

calcium carbonate

The way in which a reaction is written influences the value of the enthalpy change for the reaction. Many reactions are reversible, meaning that the product(s) of the reaction are capable of combining and reforming the reactant(s). If a reaction is written in the reverse direction, the sign of the changes. For example, we can write an equation for the reaction of calcium oxide with carbon dioxide to form calcium carbonate.

Cilia or flagella structures give protists what ability?

eating

reproduction

breathing

movement

An animal-like protist, or a protozoa. These protists have the ability to move, usually with some sort of cilia or flagella, and must obtain their energy from other sources. But obviously, they are much simpler than animals.

What is characterized by uncontrolled cell division of abnormal cells?

hepatitis

radiation

concussions

cancer

cell depletion, organ system failure, and impaired tissue injury responses. Telomerase reactivation in these mice caused extension of telomeres, reduced DNA damage, reversed neurodegeneration, and improved the function of the testes, spleen, and intestines. Thus, telomere reactivation may have potential for treating age-related diseases in humans. Cancer is characterized by uncontrolled cell division of abnormal cells. The cells accumulate mutations, proliferate uncontrollably, and can migrate to different parts of the body through a process called metastasis. Scientists have observed that cancerous cells have considerably shortened telomeres and that telomerase is active in these cells. Interestingly, only after the telomeres were shortened in the cancer cells did the telomerase become active. If the action of telomerase in these cells can be inhibited by drugs during cancer therapy, then the cancerous cells could potentially be stopped from further division.

Our global ecological footprint depends on resource use per person and what population factor?

population decrease

population fluctuation

population sample

population density

What do all sound waves begin with?

enclosing matter

oscillating matter

talking matter

vibrating matter

All sound waves begin with vibrating matter. The vibrations generate longitudinal waves that travel through matter in all directions.

Animal starch, called glycogen, is stored in the liver and where else?

hands

kidneys

nerves

muscles

Note the Pattern Because carbohydrates have a carbonyl functional group and several hydroxyl groups, they can undergo a variety of reactions. Two familiar polysaccharides are starch and cellulose, which both hydrolyze to produce thousands of glucose units. They differ only in the connection between glucose units and the amount of branching in the molecule (Figure 24.22 "The Polysaccharides Starch and Cellulose"). Starches can be coiled or branched and are hydrolyzed by the enzymes in our saliva and pancreatic juices. Animal starch, called glycogen, is stored in the liver and muscles. It consists of branched glucose units linked by bonds Saylor URL: http://www. saylor. org/books.

Kepler's laws relate to the motion of what?

the sun

continents

oceans

planets

The system is isolated from other masses. This allows us to neglect any small effects due to outside masses. The conditions are satisfied, to good approximation, by Earth’s satellites (including the Moon), by objects orbiting the Sun, and by the satellites of other planets. Historically, planets were studied first, and there is a classical set of three laws, called Kepler’s laws of planetary motion, that describe the orbits of all bodies satisfying the two previous conditions (not just planets in our solar system). These descriptive laws are named for the German astronomer Johannes Kepler (1571–1630), who devised them after careful study (over some 20 years) of a large amount of meticulously recorded observations of planetary motion done by Tycho Brahe (1546–1601). Such careful collection and detailed recording of methods and data are hallmarks of good science. Data constitute the evidence from which new interpretations and meanings can be constructed.

Colloids are used industrially as what?

solutions

organisms

impurities

catalysts

Suspensions and colloids are two common types of mixtures whose properties are in many ways intermediate between those of true solutions and heterogeneous mixtures. Asuspension is a heterogeneous mixture of particles with diameters of about 1 µm (1000 nm) that are distributed throughout a second phase. Common suspensions include paint, blood, and hot chocolate, which are solid particles in a liquid, and aerosol sprays, which are liquid particles in a gas. If the suspension is allowed to stand, the two phases will separate, which is why paints must be thoroughly stirred or shaken before use. A colloid is also a heterogeneous mixture, but the particles of a colloid are typically smaller than those of a suspension, generally in the range of 2 to about 500 nm in diameter. Colloids include fog and clouds (liquid particles in a gas), milk (solid particles in a liquid), and butter (solid particles in a solid). Other colloids are used industrially as catalysts. Unlike in a suspension, the particles in a colloid do not separate into two phases on standing. The only combination of substances that cannot produce a suspension or a colloid is a mixture of two gases because their particles are so small that they always form true solutions. The properties of suspensions, colloids, and solutions are summarized in Table 13.9 "Properties of Liquid Solutions, Colloids, and Suspensions".

What is defined as the temperature plus precipitation of an area over a long period of time?

weather

conditions

environment

climate

Climate is the temperature plus precipitation of an area. Not just today, but over a long period of time. Climate affects chemical weathering. Chemical weathering increases as:.

What manages the material and energy resources of the cell?

nucleus

cell wall

respiration

metabolism

What is the midpiece of sperm packed with?

urine

protein

glucose

mitochondria

The midpiece of the sperm is packed with mitochondria. Mitochondria are organelles in cells that produce energy. Sperm use the energy in the midpiece to move.

Dry soils are relatively unproductive because plants need a sufficient quantity of liquid water to carry out what process?

flowering

contraction

shrinkage

photosynthesis

The vitamins and minerals contained in all of the food we consume are important for all of our organ systems. however, there are certain nutrients that affect this?

chain health

mental health

abnormal health

bone health

Nutrition and Bone Tissue The vitamins and minerals contained in all of the food we consume are important for all of our organ systems. However, there are certain nutrients that affect bone health.

What type of plants supplement their mineral nutrition by digesting animals?

herbivorous

perennials

annuals

carnivorous

Daughter cells divide by what?

nucleus

electrolysis

mitosis

meiosis

The daughter cells then start to divide by meiosis . But they only go through the first of the two cell divisions of meiosis at that time. They go through the second stage of cell division after the female goes through puberty.

Phytochromes regulate many plant responses to what?

oxygen

heat

gravity

light

Carbon dioxide molecules consist of a central carbon atom bonded to how many oxygen atoms?

three

one

four

two

Carbon dioxide molecules consist of a central carbon atom bonded to 2 oxygen atoms.

Survivorship curves show the distribution of individuals in a population according to what metric?

birth rate

weight

height

age

Figure 19.4 Survivorship curves show the distribution of individuals in a population according to age. Humans and most mammals have a Type I survivorship curve, because death primarily occurs in the older years. Birds have a Type II survivorship curve, as death at any age is equally probable. Trees have a Type III survivorship curve because very few survive the younger years, but after a certain age, individuals are much more likely to survive.

Electrons are not shared equally between the two atoms in which type of covalent bonds?

solar

wide

narrow

polar

In polar covalent bonds, electrons are not shared equally between the two atoms, so one atom is slightly negative in charge and one is slightly positive in charge. In nonpolar covalent bonds, electrons are shared equally so the atoms remain neutral in charge.

What is above each leaf scar?

stipule scar

chambered pitch

lenticel

an axillary bud

Ultimately, the fluid that is lost from the blood vessels is returned through what system?

urinary

symptomatic

venous

lymphatic

None of your blood vessels are leaking this badly, or you'd be in the hospital! But your blood vessels do leak a little bit. Water and solutes pass out of the blood vessels and help form the fluid that bathes your body's tissues. Ultimately the fluid that is lost from the blood vessels is returned through the lymphatic system.

What type energy sources emit fewer or no greenhouse gases?

fossil

gas

animal

renewable

New technologies can be developed. Renewable energy sources emit fewer or no greenhouse gases. These sources are discussed in the chapter Natural Resources .

Stars spend most of their lives on the main sequence, fusing hydrogen into what?

nitrogen

neon

carbon

helium

Stars spend most of their lives on the main sequence, fusing hydrogen into helium.

What is a measure of how hot or cold the air is?

relativity

precipitation

variation

temperature

Where are more of an insect's internal organs kept?

the chest cavity

the head

the thorax

the abdomen

An insect’s abdomen contains most of the internal organs. Like other arthropods, insects have a complete digestive system. They also have an open circulatory system and central nervous system. Like other terrestrial arthropods, they have trachea for breathing air and Malphigian tubules for excretion.

What is the measure of kinetic energy of the particles in matter?

friction

energy

precipitation

temperature

Temperature is a measure of the average kinetic energy of the particles in matter. In everyday usage, temperature indicates a measure of how hot or cold an object is. Temperature is an important parameter in chemistry. When a substance changes from solid to liquid, it is because there was an increase in the temperature of the material. Chemical reactions usually proceed faster if the temperature is increased. Many unstable materials (such as enzymes) will be viable longer at lower temperatures.

What is the name for the tiny air sacs at the end of bronchioles?

ganglion

gills

vacuoles

alveoli

Finally, air passes from the bronchi into smaller passages called bronchioles. The bronchioles end in tiny air sacs called alveoli.

What is the source of most of the energy used?

the Moon

the Earth

fossil fuels

the sun

The Sun produces far more energy than humans can use. The Sun is also the source of most of the energy we use. Fossil fuels and wind energy, for example, originate with the Sun. So why don't we get all our energy from the Sun? For one reason, it's not always practical.

What flows across the membrane resulting in changes in the membrane potential?

neutrons

electrons

acids

ions

The standard reduction potential can be determined by subtracting the standard reduction potential for the reaction occurring at the anode from the standard reduction potential for the reaction occurring at this?

electrode

Spinner

plasma

cathode

The standard reduction potential can be determined by subtracting the standard reduction potential for the reaction occurring at the anode from the standard reduction potential for the reaction occurring at the cathode. The minus sign is necessary because oxidation is the reverse of reduction. E°cell = E°cathode − E°anode +0.34 V = E° 2+ − E°H + /H = E° 2+ − 0 = E° Cu.

What are proteins made up of?

atoms acids

lewis acids

detected acids

amino acids

Proteins are formed when hundreds or even thousands of amino acids form amide bonds to make polymers. Proteins play a crucial role in living organisms. A carbohydrate is a compound that has the general formula Cn(H2O)n. Many carbohydrates are relatively small molecules, such as glucose:.

What proteins synthesized in cells act as catalysts?

byproducts

hormones

virophages

enzymes

Chemical reactions constantly occur inside the cells of living things. However, under the conditions inside cells, most biochemical reactions would occur too slowly to maintain life. That’s where enzymes come in. Enzymes are catalysts in living things. Like other catalysts, they speed up chemical reactions. Enzymes are proteins that are synthesized in the cells that need them, based on instructions encoded in the cells’ DNA.

What element is the sun mostly made up of?

helium

manganese

mercury

hydrogen

The Sun is mostly hydrogen with smaller amounts of helium. The material is in the form of plasma.

What shape is the gametophyte in ferns?

diamond

circular

rectangular

heart-shaped

In ferns, the sporophyte is dominant and produces spores that germinate into a heart-shaped gametophyte.

What makes sunsets appear red?

floral scattering

wavelength scattering

reflection scattering

rayleigh scattering

Beautiful sunsets are another manifestation of Rayleigh scattering that occurs when light travels long distances through the atmosphere. The blue light and some green is scattered away, making the sun appear red.

Skeletal and muscular are examples of what type of system?

shell system

internal system

interior system

organ system

Organs are organized into organ systems such as the skeletal and muscular systems.

What is the process where light bounces back from surfaces that it cannot pass through?

absorbtion

diffraction

direction

reflection

Reflection of light occurs when light bounces back from a surface that it cannot pass through. If the surface is very smooth, the reflected light forms an image.

What are butterflies and bees an example of?

parasites

spores

species

pollinators

What are clouds that form on the ground called?

canopy

haze

smoke

fog

Clouds form when air in the atmosphere reaches the dew point. Clouds may form anywhere in the troposphere. Clouds that form on the ground are called fog .

What is formed when atoms of different elements bond together?

duality compound

univalent compound

phenotype compound

covalent compound

The two atoms that are held together in a covalent bond may be atoms of the same element or different elements. When atoms of different elements bond together, it forms a covalent compound.

Where a cell resides, how it appears, and what it does define its what?

life cycle

minute race

slowing rate

development fate