DatologyAI/sciq · Datasets at Hugging Face

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700	Many carboxylic acids occur naturally in plants and animals. Citrus fruits such as oranges and lemons contain citric acid.	Oranges and lemons are examples of fruits that contain what acid?	[ "nitric acid", "urea acid", "beryllium acid", "citric acid" ]	3
701	Atherosclerosis is the buildup of plaque inside arteries (see Figure below ). Plaque consists of cell debris, cholesterol, and other substances. Factors that contribute to plaque buildup include a high-fat diet and smoking. As plaque builds up, it narrows the arteries and reduces blood flow. You can watch an animation about atherosclerosis at these links: http://www. youtube. com/watch?v=fLonh7ZesKs and http://www. youtube. com/watch?v=qRK7-DCDKEA .	What is the term for buildup of cell debris and cholesterol inside the arteries?	[ "atherosclerosis", "fibrosis", "phimosis", "sclerosis" ]	0
702	Chemical digestion occurs mainly in the small intestine.	In the body, in which organ does chemical digestion mainly take place?	[ "kidneys", "large intestine", "liver", "small intestine" ]	3
703	Skin cancer is a disease in which skin cells grow out of control. It is caused mainly by excessive exposure to UV light. People with lighter skin are at greater risk of developing skin cancer because they have less melanin to block harmful UV radiation. The best way to prevent skin cancer is to avoid UV exposure by using sunscreen and wearing protective clothing.	Excessive exposure to what is the main cause of skin cancer?	[ "uv light", "incandescent light", "LED light", "fluorescent light" ]	0
704	Mitosis actually occurs in four phases. The phases are called prophase, metaphase, anaphase, and telophase. They are shown in Figure below and described in greater detail in the following sections.	Mitosis actually occurs in how many phases?	[ "two", "six", "four", "Seven" ]	2
705	There are two main types of lymphocytes, called B cells and T cells. Both types of lymphocytes are produced in bone marrow. They are named for the sites where they grow and mature. The B in B cells stands for bone marrow, where B cells mature. The T in T cells stands for thymus gland, where T cells mature. Both B cells and T cells must be “switched on” in order to fight a specific pathogen. Once this happens, they produce an “army” of cells that are ready to fight that particular pathogen.	Where are b cells produced in the body?	[ "lungs", "tumors", "lymphocytes", "keratinocytes" ]	2
706	Arthropods are invertebrates in the Phylum Arthropoda. They include insects, spiders, centipedes, and lobsters. Traits of arthropods include three body segments, a hard exoskeleton, and jointed appendages. The arthropod life cycle may include larva and pupa stages and the process of metamorphosis.	Three body segments, a hard exoskeleton, and jointed appendages are features of what invertebrate group, which includes spider and insects?	[ "annelid", "crustacean", "sauropod", "arthropod" ]	3
707	The other type of curved mirror, a convex mirror, is shaped like the outside of a bowl. Because of its shape, it can gather and reflect light from a wide area. As you can see in the Figure below , a convex mirror forms only virtual images that are right-side up and smaller than the actual object. You can see how a convex mirror forms an image in the animation at this URL: http://physics. slss. ie/resources/convex%20mirror. swf.	What type of mirror is shaped like the outside of a bowl?	[ "concave", "convex", "slope", "vertex" ]	1
708	We tend to think of solids as those materials that are solid at room temperature. However, all materials have melting points of some sort. Gases become solids at extremely low temperatures, and liquids will also become solid if the temperature is low enough. The Table below gives the melting points of some common materials.	When do gases and liquids become solids?	[ "at relative temperatures", "at low temperatures", "at hot temperatures", "at high temperatures" ]	1
709	The electromagnetic spectrum is the full range of wavelengths and frequencies of electromagnetic radiation. Wavelength, frequency, and energy change continuously across the electromagnetic spectrum.	The full range of wavelengths and frequencies of electromagnetic radiation make up the ____________	[ "anomalous spectrum", "electronic spectrum", "electromagnetic spectrum", "mechanical spectrum" ]	2
710	Mitochondria divide on their own by a process that resembles binary fission in prokaryotes. Mitochondria have their own circular DNA chromosome that carries genes similar to those expressed by bacteria. Mitochondria also have special ribosomes and transfer RNAs that resemble these components in prokaryotes. These features all support that mitochondria were once free-living prokaryotes. Chloroplasts Chloroplasts are one type of plastid, a group of related organelles in plant cells that are involved in the storage of starches, fats, proteins, and pigments. Chloroplasts contain the green pigment chlorophyll and play a role in photosynthesis. Genetic and morphological studies suggest that plastids evolved from the endosymbiosis of an ancestral cell that engulfed a photosynthetic cyanobacterium. Plastids are similar in size and shape to cyanobacteria and are enveloped by two or more membranes, corresponding to the inner and outer membranes of cyanobacteria. Like mitochondria, plastids also contain circular genomes and divide by a process reminiscent of prokaryotic cell division. The chloroplasts of red and green algae.	What divide on their own by a process that resembles binary fission in prokaryotes?	[ "protazoa", "mitochondria", "bacteria", "proteins" ]	1
711	In the chest, the trachea divides as it enters the lungs to form the right and left bronchi. The bronchi contain cartilage, which prevents them from collapsing. Mucus in the bronchi traps any remaining particles in air. Tiny hairs called cilia line the bronchi and sweep the particles and mucus toward the throat so they can be expelled from the body.	What are tiny hairs that line the bronchi called?	[ "antennae", "flagella", "alveoli", "cilia" ]	3
712	If a sperm does not enter an egg, the lining of the uterus breaks down. Blood and other tissues from the lining break off from the uterus. They pass through the vagina and out of the body. This is called menstruation . Menstruation is also called a menstrual period. It lasts about 4 days, on average. When the menstrual period ends, the cycle repeats. Some women feel discomfort during this process.	What cycle occurs in women of reproductive age, as a long as a sperm does not enter an egg?	[ "menopausal cycle", "menstrual cycle", "tissue cycle", "extraction cycle" ]	1
713	Corrosion is usually defined as the degradation of metals due to an electrochemical process. The formation of rust on iron, tarnish on silver, and the blue-green patina that develops on copper are all examples of corrosion. The total cost of corrosion in the United States is significant, with estimates in excess of half a trillion dollars a year.	Corrosion is usually defined as the degradation of metals due to what?	[ "crystalline process", "nuclear process", "oscillatory process", "electrochemical process" ]	3
714	A parasite generally lives in or on its host. An example of a parasite that lives in its host is the hookworm. Figure below shows two hookworms living inside a human host’s intestines. The hookworms obtain nutrients and shelter from their host, which is harmed by the loss of nutrients and blood.	What type of organism generally lives in or on its host?	[ "bacteria", "insect", "predator", "parasite" ]	3
715	Alpine tundra climates occur at high altitudes at any latitude. They are also called highland climates. These regions are very cold because they are so far above sea level. The alpine tundra climate is very similar to the polar tundra climate.	What causes the alpine tundra to be so cold?	[ "low altitude", "high altitude above sea level", "moderate altitude", "low air density" ]	1
716	Cytoskeleton. The cytoskeleton gives the cell an internal structure, like the frame of a house. In this photograph, filaments and tubules of the cytoskeleton are green and red, respectively. The blue dots are cell nuclei.	Like the frame of a house, what gives the cell an internal structure?	[ "cytoplasm", "cellulose", "cytoskeleton", "endoskeleton" ]	2
717	species that benefits and harms a host in a parasitic relationship.	A species that benefits and harms the host organism is called a what?	[ "host", "viruses", "predators", "parasite" ]	3
718		When liquid water changes to water vapor it is called?	[ "evaporation", "absorption", "transpiration", "evaporation" ]	0
719		Chewing insects mechanically damage plants and lessen the surface area of leaves for what?	[ "vegetation", "nutrients", "tissues", "photosynthesis" ]	3
720	Reptiles are tetrapods (four-legged) and ectothermic , meaning their internal temperature depends on the temperature of their environment. This is why you may see reptiles sunbathing as they use the energy from the sun to warm their bodies. Usually the sense organs of reptiles, like ears, are well developed, though snakes do not have external ears. All reptiles have advanced eyesight. Reptiles also have a sense of smell. Crocodilians, turtles, and tortoises smell like most other land vertebrates. But, some lizards, and all snakes, smell with their tongues, which is flicked out of the mouth to pick up scent molecules from the air.	Reptiles are described by what term that means their internal temperature depends on the temperature of their environment?	[ "endothermic", "ectothermic", "actinomorphic", "zygomorphic" ]	1
721	Odor receptors line the passages of the nose (see Figure below ). They sense chemicals in the air. In fact, odor receptors can sense hundreds of different chemicals. Did you ever notice that food seems to have less taste when you have a stuffy nose? This occurs because the sense of smell contributes to the sense of taste, and a stuffy nose interferes with the ability to smell.	What lines the passages of the nose and senses chemicals in the air?	[ "consumption receptors", "odor receptors", "matter receptors", "optic receptors" ]	1
722	Telomerase is typically active in germ cells and adult stem cells. It is not active in adult somatic cells. For her discovery of telomerase and its action, Elizabeth Blackburn (Figure 14.16) received the Nobel Prize for Medicine and Physiology in 2009.	Telomerase is typically active in germ cells and adult what?	[ "stem cells", "sex cells", "chromosomes", "human growth hormone" ]	0
723	Many chemists are currently working in the field of superconductivity. Superconductors are materials that are able to conduct electricity with 100% efficiency, meaning that no energy is lost during the electrical transmission, as happens with conventional conducting materials like copper cable. The challenge is to design materials that can act as superconductors at normal temperatures, as opposed to only being able to superconduct at very low temperatures.	What do you call materials able to conduct electricity with 100% efficiency, meaning that no energy is lost during the electrical transmission?	[ "electromagnets", "poor conductors", "superconductors", "super-insulators" ]	2
724	Scientific notation is a way of writing very large or very small numbers that uses exponents. Numbers are written in this format:.	What does scientific notation use to write very large or very small numbers?	[ "whole numbers", "coefficients", "exponents", "zeros" ]	2
725	Properties of sound include speed, loudness, and pitch. The speed of sound varies in different media. The loudness of sound depends on the intensity of sound waves. The pitch of sound depends on the frequency of sound waves.	Speed, loudness, and pitch are properties of what?	[ "metal", "sound", "light", "colour" ]	1
726	Radioactive nuclei and particles are represented by nuclear symbols that indicate their numbers of protons and neutrons. For example, an alpha particle (helium nucleus) is represented by the symbol , where He is the chemical symbol for helium, the subscript 2 is the number of protons, and the superscript 4 is the mass number (2 protons + 2 neutrons).	Radioactive nuclei and particles are represented by which symbols?	[ "energy", "greek", "nuclear", "compound" ]	2
727		Properties of matter can be considered physical or?	[ "liquid", "gas", "chemical", "mineral" ]	2
728	Mammalian lungs have millions of tiny air sacs called alveoli . They provide a very large surface area for gas exchange.	What are alveoli?	[ "sacs in the diaphragm", "tiny air sacs in the lungs", "tiny air natalensis in the lungs", "cilia in the throat" ]	1
729	Forces and pressures created by thermal stress are typically as great as that in the example above. Railroad tracks and roadways can buckle on hot days if they lack sufficient expansion joints. (See Figure 13.14. ) Power lines sag more in the summer than in the winter, and will snap in cold weather if there is insufficient slack. Cracks open and close in plaster walls as a house warms and cools. Glass cooking pans will crack if cooled rapidly or unevenly, because of differential contraction and the.	Railroad tracks and roadways can buckle on hot days if they lack sufficient what?	[ "expansion joints", "cartilaginous joints", "contraction joints", "attraction joints" ]	0
730	Milk is a complex mixture of water, proteins, fats, carbohydrates, and minerals. While the minerals and carbohydrates are water-soluble, the fats and some of the proteins do not dissolve but are held in suspension.	What is the name of the complex mixture that consists of water, proteins, fats, carbohydrates, and minerals?	[ "blood", "milk", "sperm", "plasma" ]	1
731	6.3 Cancer and the Cell Cycle Cancer is the result of unchecked cell division caused by a breakdown of the mechanisms regulating the cell cycle. The loss of control begins with a change in the DNA sequence of a gene that codes for one of the regulatory molecules. Faulty instructions lead to a protein that does not function as it should. Any disruption of the monitoring system can allow other mistakes to be passed on to the daughter cells. Each successive cell division will give rise to daughter cells with even more accumulated damage. Eventually, all checkpoints become nonfunctional, and rapidly reproducing cells crowd out normal cells, resulting in tumorous growth.	What disease is the result of unchecked cell division caused by a breakdown of the mechanisms regulating the cell cycle?	[ "dementia", "cancer", "gout", "diabetes" ]	1
732	Recombinant DNA technology is used in gene cloning. A clone is an exact genetic copy. Genes are cloned for many reasons, including use in medicine and in agriculture.	What is the term for an exact genetic copy?	[ "duplication", "genetic repeat", "clone", "genetic recreation" ]	2
733	Rocks on different continents that are the same age point to different locations. Only recent rocks point to the current north magnetic pole.	Where do recent rocks point towards on earth?	[ "north magnetic pole", "equator", "space", "south magnetic pole" ]	0
734		What type of cell function relies on microfilaments, which are the actin components of the cytoskeleton?	[ "muscle", "skin cells", "neurons", "nephrons" ]	0
735	Population Growth The two simplest models of population growth use deterministic equations (equations that do not account for random events) to describe the rate of change in the size of a population over time. The first of these models, exponential growth, describes theoretical populations that increase in numbers without any limits to their growth. The second model, logistic growth, introduces limits to reproductive growth that become more intense as the population size increases. Neither model adequately describes natural populations, but they provide points of comparison. Exponential Growth Charles Darwin, in developing his theory of natural selection, was influenced by the English clergyman Thomas Malthus. Malthus published his book in 1798 stating that populations with abundant natural resources grow very rapidly; however, they limit further growth by depleting their resources. The early pattern of accelerating population size is called exponential growth. The best example of exponential growth in organisms is seen in bacteria. Bacteria are prokaryotes that reproduce largely by binary fission. This division takes about an hour for many bacterial species. If 1000 bacteria are placed in a large flask with an abundant supply of nutrients (so the nutrients will not become quickly depleted), the number of bacteria will have doubled from 1000 to 2000 after just an hour. In another hour, each of the 2000 bacteria will divide, producing 4000 bacteria. After the third hour, there should be 8000 bacteria in the flask. The important concept of exponential growth is that the growth rate—the number of organisms added in each reproductive generation—is itself increasing; that is, the.	The two simplest models of population growth use what to describe the rate of change in the size of a population over time?	[ "deterministic equations", "analogous equations", "predestination equations", "wave function" ]	0
736	Dissociation is the separation of ions that occurs when a solid ionic compound dissolves.	What is the separation of ions that occurs when a solid ionic compound dissolves?	[ "decomposition", "combustion", "dissociation", "inflammation" ]	2
737	Paints can be both toxic and flammable. Paints may spill on the ground or be thrown improperly in the trash.	What do charged particles in motion generate?	[ "gravitational fields", "fission", "electricity", "magnetic fields" ]	3
738	Hydrogen bonding. Hydrogen bonding forms between a highly electronegative oxygen atom or a nitrogen atom and a hydrogen atom attached to another oxygen atom or a nitrogen atom, such as those found in polar amino acid side chains. Hydrogen bonding (as well as ionic attractions) is extremely important in both the intra- and intermolecular interactions of proteins (part (b) of http://catalog. flatworldknowledge. com/bookhub/reader/2547 - gob-ch18_s04_s01_f05). Disulfide linkages. Two cysteine amino acid units may be brought close together as the protein molecule folds. Subsequent oxidation and linkage of the sulfur atoms in the highly reactive sulfhydryl (SH) groups leads to the formation of cystine (part (c) ofhttp://catalog. flatworldknowledge. com/bookhub/reader/2547 - gob-ch18_s04_s01_f05). Intrachain disulfide linkages are found in many proteins, including insulin (yellow bars in http://catalog. flatworldknowledge. com/bookhub/reader/2547 - gob-ch18_s04_s01_f01) and have a strong stabilizing effect on the tertiary structure.	What bonding is formed in polar amino acid side chains?	[ "helium bonding", "hydrogen bonding", "calcium bonding", "carbon bonding" ]	1
739	Geologists study earthquake waves to “see” Earth's interior. Waves of energy radiate out from an earthquake’s focus. These waves are called seismic waves ( Figure below ). Seismic waves go different speeds through different materials. They change speed when they go from one type of material to another. This causes them to bend. Some seismic waves do not travel through liquids or gases. They just stop. Scientists use information from seismic waves to understand what makes up the Earth’s interior.	What is the name for the energy waves that radiate out from the center of an earthquake?	[ "deep waves", "seismic waves", "particle waves", "volcanic waves" ]	1
740	43.5 Human Pregnancy and Birth Human pregnancy begins with fertilization of an egg and proceeds through the three trimesters of gestation. The labor process has three stages (contractions, delivery of the fetus, expulsion of the placenta), each propelled by hormones. The first trimester lays down the basic structures of the body, including the limb buds, heart, eyes, and the liver. The second trimester continues the development of all of the organs and systems. The third trimester exhibits the greatest growth of the fetus and culminates in labor and delivery. Prevention of a pregnancy can be accomplished through a variety of methods including barriers, hormones, or other means. Assisted reproductive technologies may help individuals who have infertility problems.	During a human pregnancy, which trimester exhibits the greatest growth of the fetus and culminates in labor and delivery?	[ "second trimester", "first trimester", "third trimester", "fourth trimester" ]	2
741	Ecologists study ecosystems at every level, from the individual organism to the whole ecosystem and biosphere. They can ask different types of questions at each level. Examples of these questions are given in Table below , using the zebra ( Equus zebra ) as an example.	What do ecologists study at every level?	[ "ecosystems", "taxonomy", "solar system", "plants" ]	0
742		The main shaft of the penis is covered by relatively thick what?	[ "bone", "skin", "collagen", "cellulose" ]	1
743	The broadest category in the Linnaean system is the kingdom . Figure above shows the Animal Kingdom because Homo sapiens belongs to that kingdom. Other kingdoms include the Plant Kingdom, Fungus Kingdom, and Protist Kingdom.	What is the broadest category in the linnaean system?	[ "phylum", "class", "kingdom", "domain" ]	2
744	Most chemical reactions within organisms would be impossible under the normal conditions within cell. For example, the body temperature of most organisms is too low for reactions to occur quickly enough to carry out life processes. Reactants may also be present in such low concentrations that it is unlikely they will meet and collide. Therefore, the rate of most biochemical reactions must be increased by a catalyst. A catalyst is a chemical that speeds up chemical reactions. In organisms, catalysts are called enzymes .	Reactants may also be present in such low concentrations that it is unlikely they will meet and do what?	[ "collide", "explode", "depart", "melt" ]	0
745	Insects range in length from less than a millimeter to about the length of your arm. They can be found in most habitats, but they are mainly terrestrial. Many can fly, so they are also aerial. Like other arthropods, insects have a head, thorax, and abdomen. They have a wide variety of appendages, including six legs attached to the thorax.	The three main body segments of an arthropod are head, thorax, and what?	[ "abdomen", "tail", "legs", "gluteus" ]	0
746	This Concept deals with some Earth basics. Earth is a planet and has the characteristics of a planet. Like other planets, it is nearly round. This is because it has enough mass for its gravity to pull material into a round shape. Earth's gravity has also pulled in small objects, like asteroids. So the planet's orbit is cleared. Earth rotates on its axis and revolves around its star. As a result of its rotation, Earth has a day-night cycle. The tilt of its axis creates the seasons. Earth has layers from crust to mantle to core. The core is divided into a liquid outer core and a solid inner core. The liquid outer core has convection, which generates the magnetic field. The mantle is solid rock. The crust has two major types: continental and oceanic. The crust and uppermost mantle make up the lithosphere. Beneath the lithosphere is the asthenosphere. The lithosphere is brittle and will break. The asthenosphere can flow.	What is the term for what the earth rotates on?	[ "axis", "tip", "compass", "radius" ]	0
747		What is the end product of glycolysis?	[ "hydrolysis", "fructose", "gluclose", "pyruvate" ]	3
748	A vector is any quantity that has magnitude and direction. A scalar is any quantity that has magnitude but no direction. Displacement and velocity are vectors, whereas distance and speed are scalars. In one-dimensional motion, direction is specified by a plus or minus sign to signify left or right, up or down, and the like.	A vector is any quantity that has magnitude and what?	[ "direction", "length", "latitude", "longitude" ]	0
749	Mineral Storage, Energy Storage, and Hematopoiesis On a metabolic level, bone tissue performs several critical functions. For one, the bone matrix acts as a reservoir for a number of minerals important to the functioning of the body, especially calcium, and phosphorus. These minerals, incorporated into bone tissue, can be released back into the bloodstream to maintain levels needed to support physiological processes. Calcium ions, for example, are essential for muscle contractions and controlling the flow of other ions involved in the transmission of nerve impulses. Bone also serves as a site for fat storage and blood cell production. The softer connective tissue that fills the interior of most bone is referred to as bone marrow (Figure 6.5). There are two types of bone marrow: yellow marrow and red marrow. Yellow marrow contains adipose tissue; the triglycerides stored in the adipocytes of the tissue can serve as a source of.	The softer connective tissue that fills the interior of most bone is referred to as what?	[ "solid marrow", "liquid marrow", "attached marrow", "bone marrow" ]	3
750		What is stored mainly in liver and muscle cells by humans and other vertebrates?	[ "glycogen", "amylopectin", "glucose", "protein" ]	0
751	Pedalfer is the soil common in deciduous forests. Pedalfer is dark brown and fertile.	What soil is common in deciduous forests?	[ "pedalfer", "sandy soil", "loam", "xerophyte" ]	0
752	Ammeters and voltmeters are cleverly designed for the way they are used. Ammeters measure the current of a circuit, and voltmeters measure the voltage drop across a resistor. It is important in the design and use of these meters that they don't change the circuit in such a way as to influence the readings. While both types of meters are technically resistors, they are specifically designed to make their readings without changing the circuit itself.	What do voltmeters measure across a resistor?	[ "amplitude", "the vibration drop", "the voltage drop", "energy loss" ]	2
753	Cardiac muscle is found only in the walls of the heart. When cardiac muscle contracts, the heart beats and pumps blood. Cardiac muscle contains a great many mitochondria, which produce ATP for energy. This helps the heart resist fatigue. Contractions of cardiac muscle are involuntary, like those of smooth muscle. Cardiac muscle, like skeletal muscle, is arranged in bundles, so it appears striated , or striped.	Cardiac muscle is found only in which part of the heart?	[ "the ridges", "the bottom", "the walls", "the left side" ]	2
754	Safety precautions are in place to help prevent accidents. Always wear personal protective equipment such as goggles and gloves when recommended to do so by your teacher.	Wearing personal protective equipment such as goggles and gloves during an experiment is an example of what?	[ "office politics", "safety precaution", "pollution precaution", "lab organization" ]	1
755	When the pH of a solution is known, the concentration of the hydrogen ion can be calculated. The inverse of the logarithm (or antilog) is the 10 x key on a calculator.	The concentration of the hydrogen ion in a solution can be calculated when what is known?	[ "velocity", "ph", "temperature", "pressure" ]	1
756	White blood cells also make chemicals that cause a fever. A fever is a higher-than-normal body temperature. Normal human body temperature is 98.6°F (37°C). Most bacteria and viruses that infect people reproduce fastest at this temperature. When the temperature is higher, the pathogens cannot reproduce as fast, so the body raises the temperature to kill them. A fever also causes the immune system to make more white blood cells. In these ways, a fever helps the body fight infection.	A fever also causes the immune system to make more of what?	[ "insulin", "white blood cells", "urea", "red blood cells" ]	1
757	Vascular plants also have roots, stems, and leaves.	Vascular plants all have roots, stems, and what?	[ "leaves", "flowers", "beans", "fruits" ]	0
758		In an aqueous solution, what is the solvent?	[ "oil", "water", "any liquid", "saltwater" ]	1
759	Scientists think that protists are the oldest eukaryotes. If so, they must have evolved from prokaryotes. How did this happen? How did cells without organelles acquire them? What was the origin of mitochondria, chloroplasts, and other organelles?.	What do scientists think to be the oldest eukaryotes?	[ "ciliate", "protists", "arthropods", "bivalves" ]	1
760	Figure 8.7 Bones of the Wrist and Hand The eight carpal bones form the base of the hand. These are arranged into proximal and distal rows of four bones each. The metacarpal bones form the palm of the hand. The thumb and fingers consist of the phalanx bones.	Carpal, metacarpal and phalanx bones comprise what part of the body?	[ "foot", "pelvis", "thumb", "hand" ]	3
761	The first seed plants formed seeds in cones. Cones are made up of overlapping scales, which are modified leaves (see Figure below ). Male cones contain pollen, and female cones contain eggs. Seeds also develop in female cones. Modern seed plants that produce seeds in cones are called gymnosperms .	How did the first seed plants form seeds?	[ "in stems", "in leaves", "in cones", "in folds" ]	2
762	High power microscopic photo of the upper part of a Winter Jasmine leaf. Viewed under a microscope many green chloroplasts are visible.	What green cell structures of a leaf are visible under a high power microscope?	[ "chloroplasts", "fibroblasts", "golgi apparatus", "veins" ]	0
763	The reaction rate indicates how fast the reaction proceeds.	What indicates the speed at which a reaction proceeds?	[ "reaction scale", "the transform rate", "the reaction rate", "time zone" ]	2
764	Mediterranean climates are found on the western coasts of continents. The latitudes are between 30° and 45°. The coast of California has a Mediterranean climate. Temperatures are mild and rainfall is moderate. Most of the rain falls in the winter, and summers are dry. To make it through the dry summers, short woody plants are common.	What type of climate does the coast of california have?	[ "rainforest", "tropical", "arctic", "mediterranean" ]	3
765	Figure 11.7 Solutions of nonelectrolytes such as ethanol do not contain dissolved ions and cannot conduct electricity. Solutions of electrolytes contain ions that permit the passage of electricity. The conductivity of an electrolyte solution is related to the strength of the electrolyte.	Solutions of nonelectrolytes such as ethanol do not contain dissolved ions and cannot conduct what?	[ "light", "electricity", "current", "sound" ]	1
766		Most diplomonads and parabasalids are found in what kind of environment?	[ "enzymatic", "acidic", "skeletal", "anaerobic" ]	3
767	Physical properties include the state of matter and its color and odor. For example, oxygen is a colorless, odorless gas. Chlorine is a greenish gas with a strong, sharp odor. Other physical properties include hardness, freezing and boiling points, the ability to dissolve in other substances, and the ability to conduct heat or electricity. These properties are demonstrated in Figure below . Can you think of other physical properties?.	Oxygen is an element in what form of matter?	[ "liquid", "solid", "gas", "plasma" ]	2
768		What do experts estimate is the cause for the extinction of hundreds of species every year?	[ "migration", "human activities", "intraspecies competition", "predation" ]	1
769	Chemistry is the study of matter and the changes that matter can undergo.	What branch of science is concerned with matter and the changes that it can undergo?	[ "chemistry", "geology", "biology", "physiology" ]	0
770	No charge is actually created or destroyed when charges are separated as we have been discussing. Rather, existing charges are moved about. In fact, in all situations the total amount of charge is always constant. This universally obeyed law of nature is called the law of conservation of charge. Law of Conservation of Charge Total charge is constant in any process.	No charge is actually created or destroyed when charges are separated as we have been discussing. rather, existing charges are moved about. in fact, in all situations the total amount of charge is always this?	[ "more", "smaller", "constant", "less" ]	2
771	The plasma membrane contains molecules other than phospholipids, primarily other lipids and proteins. The green molecules in Figure below , for example, are the lipid cholesterol. Molecules of cholesterol help the plasma membrane keep its shape. Many of the proteins in the plasma membrane assist other substances in crossing the membrane.	What type of molecules help the plasma membrane keep its shape?	[ "proteins", "metabolic", "magnesium", "cholesterol" ]	3
772	Energy must constantly be added to an ecosystem for use by organisms. Matter, on the other hand, is continuously recycled through ecosystems.	Unlike matter, which is continuously recycled through ecosystems, what must constantly be added to an ecosystem for use by organisms?	[ "carbon", "fuel", "energy", "hydrogen" ]	2
773	Ocean water is an example of a liquid. A liquid is matter that has a fixed volume but not a fixed shape. Instead, a liquid takes the shape of its container. If the volume of a liquid is less than the volume of its container, the top surface will be exposed to the air, like the oil in the bottles in Figure below .	What form of matter has a fixed volume but not a fixed shape?	[ "liquid", "mixture", "solid", "gas" ]	0
774	6.5 \| Fractures: Bone Repair By the end of this section, you will be able to: • Differentiate among the different types of fractures • Describe the steps involved in bone repair A fracture is a broken bone. It will heal whether or not a physician resets it in its anatomical position. If the bone is not reset correctly, the healing process will keep the bone in its deformed position. When a broken bone is manipulated and set into its natural position without surgery, the procedure is called a closed reduction. Open reduction requires surgery to expose the fracture and reset the bone. While some fractures can be minor, others are quite severe and result in grave complications. For example, a fractured diaphysis of the femur has the potential to release fat globules into the bloodstream. These can become lodged in the capillary beds of the lungs, leading to respiratory distress and if not treated quickly, death.	Why is closed reduction simpler than open reduction in bone repair?	[ "no treatment needed", "no pain pills needed", "no surgery needed", "no medicine needed" ]	2
775		What do methanogens act as in sewage treatment plants?	[ "fertilizers", "killers", "creators", "as decomposers" ]	3
776	Figure 45.9 When resources are unlimited, populations exhibit exponential growth, resulting in a J-shaped curve. When resources are limited, populations exhibit logistic growth. In logistic growth, population expansion decreases as resources become scarce, and it levels off when the carrying capacity of the environment is reached, resulting in an S-shaped curve.	When resources are limited, populations exhibit what type of growth?	[ "efficient growth", "logistic growth", "component growth", "lasting growth" ]	1
777	35.3 The Central Nervous System The vertebrate central nervous system contains the brain and the spinal cord, which are covered and protected by three meninges. The brain contains structurally and functionally defined regions. In mammals, these include the cortex (which can be broken down into four primary functional lobes: frontal, temporal, occipital, and parietal), basal ganglia, thalamus, hypothalamus, limbic system, cerebellum, and brainstem—although structures in some of these designations overlap. While functions may be primarily localized to one structure in the brain, most complex functions, like language and sleep, involve neurons in multiple brain regions. The spinal cord is the information superhighway that connects the brain with the rest of the body through its connections with peripheral nerves. It transmits sensory and motor input and also controls motor reflexes.	What protects the brain and spinal cord in the central nervous system?	[ "Flexing", "neutrophils", "dermis", "meninges" ]	3
778	Adding energy to matter gives its atoms or molecules the ability to resist some of the forces holding them together. For example, heating ice to its melting point (0°C) gives its molecules enough energy to move. The ice melts and becomes liquid water. Similarly, heating liquid water to its boiling point (100°C) gives its molecules enough energy to pull apart from one another so they no longer have contact. The liquid water vaporizes and becomes water vapor.	Heating ice to its melting point (0°c) gives its molecules enough energy to do what?	[ "move", "evaporate", "freeze", "settle" ]	0
779		What occur in arteries that can cause heart attacks and strokes?	[ "clots", "toxins", "tumors", "lesions" ]	0
780	Water pollution comes from many sources. One of the biggest sources is runoff. Runoff picks up chemicals such as fertilizer from agricultural fields, lawns, and golf courses. It carries the chemicals to bodies of water. The added nutrients from fertilizer often cause excessive growth of algae, creating algal blooms (see Figure below ). The algae use up oxygen in the water so that other aquatic organisms cannot survive. This has occurred over large areas of the ocean, creating dead zones , where low oxygen levels have killed all ocean life. A very large dead zone exists in the Gulf of Mexico. Measures that can help prevent these problems include cutting down on fertilizer use. Preserving wetlands also helps because wetlands filter runoff water.	The added nutrients from fertilizer often cause excessive growth of what organism?	[ "mushrooms", "sediments", "crustaceans", "algae" ]	3
781	As decibel levels get higher, sound waves have greater intensity and sounds are louder. For every 10-decibel increase in the intensity of sound, loudness is 10 times greater.	An increase in what levels results in sound waves that are louder and of greater intensity?	[ "radiation levels", "heat levels", "decibel levels", "height levels" ]	2
782	Two plates may slide past each other in opposite directions. This is called a transform plate boundary . The plates meet at a transform fault . As you might imagine, plates do not slide past each other easily. These plate boundaries experience massive earthquakes. The world’s best known transform fault is the San Andreas Fault in California ( Figure below ). At this fault, the Pacific and North American plates grind past each other. Transform plate boundaries are common as offsets along mid-ocean ridges. They are very small compared to transform faults on land.	What is it called when two plates slide past each other in opposite directions?	[ "transform plate boundary", "transformation", "plate divergence", "tectonic movement" ]	0
783	Friction occurs because no surface is perfectly smooth.	What force occurs because no surface is perfectly smooth?	[ "vibration", "friction", "gravity", "tension" ]	1
784	Lymph capillaries collect fluid that leaks out from blood capillaries.	What structure collect fluid that leaks out from blood capillaries?	[ "pulmonary capillaries", "lymph capillaries", "alveoli", "varicose veins" ]	1
785	Neptune is shown in Figure below . It is the eighth planet from the Sun. Neptune is so far away you need a telescope to see it from Earth. Neptune is the most distant planet in our solar system. It is nearly 4.5 billion kilometers (2.8 billion miles) from the Sun. One orbit around the Sun takes Neptune 165 Earth years.	What is the eighth planet from our sun?	[ "mars", "uranus", "earth", "neptune" ]	3
786	Prokaryotic cells are cells without a nucleus. The DNA in prokaryotic cells is in the cytoplasm rather than enclosed within a nuclear membrane. Prokaryotic cells are found in single-celled organisms, such as bacteria, like the one shown in Figure below . Organisms with prokaryotic cells are called prokaryotes . They were the first type of organisms to evolve and are still the most common organisms today.	Where is dna located in prokaryotic cells?	[ "ribosomes", "mitochondria", "cytoskeleton", "cytoplasm" ]	3
787	Water’s Solvent Properties Since water is a polar molecule with slightly positive and slightly negative charges, ions and polar molecules can readily dissolve in it. Therefore, water is referred to as a solvent, a substance capable of dissolving other polar molecules and ionic compounds. The charges associated with these molecules will form hydrogen bonds with water, surrounding the particle with water molecules. This is referred to as a sphere of hydration, or a hydration shell, as illustrated in Figure 2.15 and serves to keep the particles separated or dispersed in the water. When ionic compounds are added to water, the individual ions react with the polar regions of the water molecules and their ionic bonds are disrupted in the process of dissociation. Dissociation occurs when atoms or groups of atoms break off from molecules and form ions. Consider table salt (NaCl, or sodium chloride): when NaCl crystals are added to water, the molecules of NaCl dissociate into Na+ and Cl– ions, and spheres of hydration form around the ions, illustrated in Figure 2.15. The positively charged sodium ion is surrounded by the partially negative charge of the water molecule’s oxygen. The negatively charged chloride ion is surrounded by the partially positive charge of the hydrogen on the water molecule.	Water is considered a what since it is a polar molecule with slightly positive and slightly negative charges, so ions and polar molecules can readily dissolve in it?	[ "osmotic", "solute", "pigment", "solvent" ]	3
788	The pressure inside a container is dependent on the amount of gas inside the container. If the basketball does not bounce high enough, the official could remedy the situation by using a hand pump and adding more air to the ball. Conversely, if it bounces too high, he could let some air out of the ball.	The pressure inside a container is dependent on the amount of what inside the container?	[ "emissions", "air", "gas", "liquids" ]	2
789	Some seed plants evolved another major adaptation. This was the formation of seeds in flowers. Flowers are plant structures that contain male and/or female reproductive organs.	What are plant structures that contain male and/or female reproductive organs?	[ "leaves", "stems", "flowers", "roots" ]	2
790	Each species has a particular way of making a living. This is called its niche . You can see the niche of a lion in Figure below . A lion makes its living by hunting and eating other animals. Each species also has a certain place where it is best suited to live. This is called its habitat . The lion’s habitat is a grassland. Why is a lion better off in a grassland than in a forest?.	Each species has a particular way of making a living which is called its what?	[ "life-cycle", "system", "habit", "niche" ]	3
791	One thing to note about equilibrium is that the reactions do not stop; both the forward reaction and the reverse reaction continue to occur. They both occur at the same rate, so any overall change by one reaction is cancelled by the reverse reaction. We say that chemical equilibrium is dynamic, rather than static. Also, because both reactions are occurring simultaneously, the equilibrium can be written backward. For example, representing an equilibrium as.	Both the forward reaction and the reverse reaction continue to occur, so chemical equilibrium is said to be what, rather than static?	[ "fluid", "dynamic", "abrasive", "stable" ]	1
792	The Lymphatic System Lymph is the watery fluid that bathes tissues and organs and contains protective white blood cells but does not contain erythrocytes. Lymph moves about the body through the lymphatic system, which is made up of vessels, lymph ducts, lymph glands, and organs, such as tonsils, adenoids, thymus, and spleen. Although the immune system is characterized by circulating cells throughout the body, the regulation, maturation, and intercommunication of immune factors occur at specific sites. The blood circulates immune cells, proteins, and other factors through the body. Approximately 0.1 percent of all cells in the blood are leukocytes, which include monocytes (the precursor of macrophages) and lymphocytes. Most cells in the blood are red blood cells. Cells of the immune system can travel between the distinct lymphatic and blood circulatory systems, which are separated by interstitial space, by a process called extravasation (passing through to surrounding tissue). Recall that cells of the immune system originate from stem cells in the bone marrow. B cell maturation occurs in the bone marrow, whereas progenitor cells migrate from the bone marrow and develop and mature into naïve T cells in the organ called the thymus. On maturation, T and B lymphocytes circulate to various destinations. Lymph nodes scattered throughout the body house large populations of T and B cells, dendritic cells, and macrophages (Figure 17.19). Lymph gathers antigens as it drains from tissues. These antigens then are filtered through lymph nodes before the lymph is returned to circulation. APCs in the lymph nodes capture and process antigens and inform nearby lymphocytes about potential pathogens.	What is the watery fluid that bathes tissues and organs and contains protective white blood cells but does not contain erythrocytes?	[ "lymph", "stomach", "secretion", "basil" ]	0
793	Adult tunicates are barrel-shaped. They have two openings that siphon water into and out of the body. The flow of water provides food for filter feeding. Tunicates reproduce sexually. Each individual produces both male and female gametes. However, they avoid self-fertilization. Tunicates can also reproduce asexually by budding.	How many openings do adult tunicates have that siphon water in and out of the body?	[ "three", "two", "four", "one" ]	1
794	The combined forces acting on an object are called the net force. When forces act in opposite directions, they are subtracted to yield the net force. When they act in the same direction, they are added to yield the net force.	What is the term for the combined forces acting on an object?	[ "total impact", "net force", "critical force", "blunt force" ]	1
795	The first stage of photosynthesis is called the light reactions. During this stage, light is absorbed and transformed to chemical energy in the bonds of NADPH and ATP. You can follow the process in the Figure below as you read about it below.	What is the name of the first stage of photosynthesis?	[ "light reactions", "consumption", "absorption", "contamination" ]	0
796	Birds are endothermic tetrapod vertebrates. They are bipedal, which means they walk on two legs. Birds also lay amniotic eggs, and the eggs have hard, calcium carbonate shells. Although birds are the most recent class of vertebrates to evolve, they are now the most numerous vertebrates on Earth. Why have birds been so successful? What traits allowed them to increase and diversify so rapidly?.	What are endothermic tetrapod vertebrates most commonly called?	[ "mammals", "birds", "insects", "reptiles" ]	1
797	It literally jumps by way of a chemical transmitter. Notice the two cells are not connected, but separated by a small gap. The synapse. The space between a neuron and the next cell.	What is the space between a neuron and the next cell?	[ "the synapse", "dendritic gap", "neurotransmitter passage", "cell divide" ]	0
798	In the Figure below , we see the structures of some common classes of lipids. Free fatty acids are carboxylic acids that contain long hydrocarbon chains. Saturated fatty acids are alkanes with a single carboxylic acid, whereas unsaturated fatty acids contain one or more C-C double bonds. Fatty acids often form esters with one of the alcohol functional groups on glycerol , a three carbon chain in which each carbon is bonded to one OH group. Triglycerides are common structures, in which all three of these OH groups are esterified with a fatty acid. The three fatty acids in a triglyceride may be the same or different. Another common structure is a phospholipid, in which two of the alcohols in glycerol form esters with fatty acids, and the third is connected to a very polar phosphorus-containing group.	Free fatty acids are carboxylic acids that contain long chains of what?	[ "hydrocarbons", "vapors", "particles", "lipds" ]	0
799	Macronutrients are nutrients the body needs in relatively large amounts. They include carbohydrates, proteins, lipids, and water.	What do you call nutrients that your body needs in fairly large amounts?	[ "antioxidants", "macronutrients", "super foods", "B-complex" ]	1

700

Many carboxylic acids occur naturally in plants and animals. Citrus fruits such as oranges and lemons contain citric acid.

Oranges and lemons are examples of fruits that contain what acid?

[ "nitric acid", "urea acid", "beryllium acid", "citric acid" ]

3

701

Atherosclerosis is the buildup of plaque inside arteries (see Figure below ). Plaque consists of cell debris, cholesterol, and other substances. Factors that contribute to plaque buildup include a high-fat diet and smoking. As plaque builds up, it narrows the arteries and reduces blood flow. You can watch an animation about atherosclerosis at these links: http://www. youtube. com/watch?v=fLonh7ZesKs and http://www. youtube. com/watch?v=qRK7-DCDKEA .

What is the term for buildup of cell debris and cholesterol inside the arteries?

[ "atherosclerosis", "fibrosis", "phimosis", "sclerosis" ]

0

702

Chemical digestion occurs mainly in the small intestine.

In the body, in which organ does chemical digestion mainly take place?

[ "kidneys", "large intestine", "liver", "small intestine" ]

3

703

Skin cancer is a disease in which skin cells grow out of control. It is caused mainly by excessive exposure to UV light. People with lighter skin are at greater risk of developing skin cancer because they have less melanin to block harmful UV radiation. The best way to prevent skin cancer is to avoid UV exposure by using sunscreen and wearing protective clothing.

Excessive exposure to what is the main cause of skin cancer?

[ "uv light", "incandescent light", "LED light", "fluorescent light" ]

0

704

Mitosis actually occurs in four phases. The phases are called prophase, metaphase, anaphase, and telophase. They are shown in Figure below and described in greater detail in the following sections.

Mitosis actually occurs in how many phases?

[ "two", "six", "four", "Seven" ]

2

705

There are two main types of lymphocytes, called B cells and T cells. Both types of lymphocytes are produced in bone marrow. They are named for the sites where they grow and mature. The B in B cells stands for bone marrow, where B cells mature. The T in T cells stands for thymus gland, where T cells mature. Both B cells and T cells must be “switched on” in order to fight a specific pathogen. Once this happens, they produce an “army” of cells that are ready to fight that particular pathogen.

Where are b cells produced in the body?

[ "lungs", "tumors", "lymphocytes", "keratinocytes" ]

2

706

Arthropods are invertebrates in the Phylum Arthropoda. They include insects, spiders, centipedes, and lobsters. Traits of arthropods include three body segments, a hard exoskeleton, and jointed appendages. The arthropod life cycle may include larva and pupa stages and the process of metamorphosis.

Three body segments, a hard exoskeleton, and jointed appendages are features of what invertebrate group, which includes spider and insects?

[ "annelid", "crustacean", "sauropod", "arthropod" ]

3

707

The other type of curved mirror, a convex mirror, is shaped like the outside of a bowl. Because of its shape, it can gather and reflect light from a wide area. As you can see in the Figure below , a convex mirror forms only virtual images that are right-side up and smaller than the actual object. You can see how a convex mirror forms an image in the animation at this URL: http://physics. slss. ie/resources/convex%20mirror. swf.

What type of mirror is shaped like the outside of a bowl?

[ "concave", "convex", "slope", "vertex" ]

1

708

We tend to think of solids as those materials that are solid at room temperature. However, all materials have melting points of some sort. Gases become solids at extremely low temperatures, and liquids will also become solid if the temperature is low enough. The Table below gives the melting points of some common materials.

When do gases and liquids become solids?

[ "at relative temperatures", "at low temperatures", "at hot temperatures", "at high temperatures" ]

1

709

The electromagnetic spectrum is the full range of wavelengths and frequencies of electromagnetic radiation. Wavelength, frequency, and energy change continuously across the electromagnetic spectrum.

The full range of wavelengths and frequencies of electromagnetic radiation make up the ____________

[ "anomalous spectrum", "electronic spectrum", "electromagnetic spectrum", "mechanical spectrum" ]

2

710

Mitochondria divide on their own by a process that resembles binary fission in prokaryotes. Mitochondria have their own circular DNA chromosome that carries genes similar to those expressed by bacteria. Mitochondria also have special ribosomes and transfer RNAs that resemble these components in prokaryotes. These features all support that mitochondria were once free-living prokaryotes. Chloroplasts Chloroplasts are one type of plastid, a group of related organelles in plant cells that are involved in the storage of starches, fats, proteins, and pigments. Chloroplasts contain the green pigment chlorophyll and play a role in photosynthesis. Genetic and morphological studies suggest that plastids evolved from the endosymbiosis of an ancestral cell that engulfed a photosynthetic cyanobacterium. Plastids are similar in size and shape to cyanobacteria and are enveloped by two or more membranes, corresponding to the inner and outer membranes of cyanobacteria. Like mitochondria, plastids also contain circular genomes and divide by a process reminiscent of prokaryotic cell division. The chloroplasts of red and green algae.

What divide on their own by a process that resembles binary fission in prokaryotes?

[ "protazoa", "mitochondria", "bacteria", "proteins" ]

1

711

In the chest, the trachea divides as it enters the lungs to form the right and left bronchi. The bronchi contain cartilage, which prevents them from collapsing. Mucus in the bronchi traps any remaining particles in air. Tiny hairs called cilia line the bronchi and sweep the particles and mucus toward the throat so they can be expelled from the body.

What are tiny hairs that line the bronchi called?

[ "antennae", "flagella", "alveoli", "cilia" ]

3

712

If a sperm does not enter an egg, the lining of the uterus breaks down. Blood and other tissues from the lining break off from the uterus. They pass through the vagina and out of the body. This is called menstruation . Menstruation is also called a menstrual period. It lasts about 4 days, on average. When the menstrual period ends, the cycle repeats. Some women feel discomfort during this process.

What cycle occurs in women of reproductive age, as a long as a sperm does not enter an egg?

[ "menopausal cycle", "menstrual cycle", "tissue cycle", "extraction cycle" ]

1

713

Corrosion is usually defined as the degradation of metals due to an electrochemical process. The formation of rust on iron, tarnish on silver, and the blue-green patina that develops on copper are all examples of corrosion. The total cost of corrosion in the United States is significant, with estimates in excess of half a trillion dollars a year.

Corrosion is usually defined as the degradation of metals due to what?

[ "crystalline process", "nuclear process", "oscillatory process", "electrochemical process" ]

3

714

A parasite generally lives in or on its host. An example of a parasite that lives in its host is the hookworm. Figure below shows two hookworms living inside a human host’s intestines. The hookworms obtain nutrients and shelter from their host, which is harmed by the loss of nutrients and blood.

What type of organism generally lives in or on its host?

[ "bacteria", "insect", "predator", "parasite" ]

3

715

Alpine tundra climates occur at high altitudes at any latitude. They are also called highland climates. These regions are very cold because they are so far above sea level. The alpine tundra climate is very similar to the polar tundra climate.

What causes the alpine tundra to be so cold?

[ "low altitude", "high altitude above sea level", "moderate altitude", "low air density" ]

1

716

Cytoskeleton. The cytoskeleton gives the cell an internal structure, like the frame of a house. In this photograph, filaments and tubules of the cytoskeleton are green and red, respectively. The blue dots are cell nuclei.

Like the frame of a house, what gives the cell an internal structure?

[ "cytoplasm", "cellulose", "cytoskeleton", "endoskeleton" ]

2

717

species that benefits and harms a host in a parasitic relationship.

A species that benefits and harms the host organism is called a what?

[ "host", "viruses", "predators", "parasite" ]

3

718

When liquid water changes to water vapor it is called?

[ "evaporation", "absorption", "transpiration", "evaporation" ]

0

719

Chewing insects mechanically damage plants and lessen the surface area of leaves for what?

[ "vegetation", "nutrients", "tissues", "photosynthesis" ]

3

720

Reptiles are tetrapods (four-legged) and ectothermic , meaning their internal temperature depends on the temperature of their environment. This is why you may see reptiles sunbathing as they use the energy from the sun to warm their bodies. Usually the sense organs of reptiles, like ears, are well developed, though snakes do not have external ears. All reptiles have advanced eyesight. Reptiles also have a sense of smell. Crocodilians, turtles, and tortoises smell like most other land vertebrates. But, some lizards, and all snakes, smell with their tongues, which is flicked out of the mouth to pick up scent molecules from the air.

Reptiles are described by what term that means their internal temperature depends on the temperature of their environment?

[ "endothermic", "ectothermic", "actinomorphic", "zygomorphic" ]

1

721

Odor receptors line the passages of the nose (see Figure below ). They sense chemicals in the air. In fact, odor receptors can sense hundreds of different chemicals. Did you ever notice that food seems to have less taste when you have a stuffy nose? This occurs because the sense of smell contributes to the sense of taste, and a stuffy nose interferes with the ability to smell.

What lines the passages of the nose and senses chemicals in the air?

[ "consumption receptors", "odor receptors", "matter receptors", "optic receptors" ]

1

722

Telomerase is typically active in germ cells and adult stem cells. It is not active in adult somatic cells. For her discovery of telomerase and its action, Elizabeth Blackburn (Figure 14.16) received the Nobel Prize for Medicine and Physiology in 2009.

Telomerase is typically active in germ cells and adult what?

[ "stem cells", "sex cells", "chromosomes", "human growth hormone" ]

0

723

Many chemists are currently working in the field of superconductivity. Superconductors are materials that are able to conduct electricity with 100% efficiency, meaning that no energy is lost during the electrical transmission, as happens with conventional conducting materials like copper cable. The challenge is to design materials that can act as superconductors at normal temperatures, as opposed to only being able to superconduct at very low temperatures.

What do you call materials able to conduct electricity with 100% efficiency, meaning that no energy is lost during the electrical transmission?

[ "electromagnets", "poor conductors", "superconductors", "super-insulators" ]

2

724

Scientific notation is a way of writing very large or very small numbers that uses exponents. Numbers are written in this format:.

What does scientific notation use to write very large or very small numbers?

[ "whole numbers", "coefficients", "exponents", "zeros" ]

2

725

Properties of sound include speed, loudness, and pitch. The speed of sound varies in different media. The loudness of sound depends on the intensity of sound waves. The pitch of sound depends on the frequency of sound waves.

Speed, loudness, and pitch are properties of what?

[ "metal", "sound", "light", "colour" ]

1

726

Radioactive nuclei and particles are represented by nuclear symbols that indicate their numbers of protons and neutrons. For example, an alpha particle (helium nucleus) is represented by the symbol , where He is the chemical symbol for helium, the subscript 2 is the number of protons, and the superscript 4 is the mass number (2 protons + 2 neutrons).

Radioactive nuclei and particles are represented by which symbols?

[ "energy", "greek", "nuclear", "compound" ]

2

727

Properties of matter can be considered physical or?

[ "liquid", "gas", "chemical", "mineral" ]

2

728

Mammalian lungs have millions of tiny air sacs called alveoli . They provide a very large surface area for gas exchange.

What are alveoli?

[ "sacs in the diaphragm", "tiny air sacs in the lungs", "tiny air natalensis in the lungs", "cilia in the throat" ]

1

729

Forces and pressures created by thermal stress are typically as great as that in the example above. Railroad tracks and roadways can buckle on hot days if they lack sufficient expansion joints. (See Figure 13.14. ) Power lines sag more in the summer than in the winter, and will snap in cold weather if there is insufficient slack. Cracks open and close in plaster walls as a house warms and cools. Glass cooking pans will crack if cooled rapidly or unevenly, because of differential contraction and the.

Railroad tracks and roadways can buckle on hot days if they lack sufficient what?

[ "expansion joints", "cartilaginous joints", "contraction joints", "attraction joints" ]

0

730

Milk is a complex mixture of water, proteins, fats, carbohydrates, and minerals. While the minerals and carbohydrates are water-soluble, the fats and some of the proteins do not dissolve but are held in suspension.

What is the name of the complex mixture that consists of water, proteins, fats, carbohydrates, and minerals?

[ "blood", "milk", "sperm", "plasma" ]

1

731

6.3 Cancer and the Cell Cycle Cancer is the result of unchecked cell division caused by a breakdown of the mechanisms regulating the cell cycle. The loss of control begins with a change in the DNA sequence of a gene that codes for one of the regulatory molecules. Faulty instructions lead to a protein that does not function as it should. Any disruption of the monitoring system can allow other mistakes to be passed on to the daughter cells. Each successive cell division will give rise to daughter cells with even more accumulated damage. Eventually, all checkpoints become nonfunctional, and rapidly reproducing cells crowd out normal cells, resulting in tumorous growth.

What disease is the result of unchecked cell division caused by a breakdown of the mechanisms regulating the cell cycle?

[ "dementia", "cancer", "gout", "diabetes" ]

1

732

Recombinant DNA technology is used in gene cloning. A clone is an exact genetic copy. Genes are cloned for many reasons, including use in medicine and in agriculture.

What is the term for an exact genetic copy?

[ "duplication", "genetic repeat", "clone", "genetic recreation" ]

2

733

Rocks on different continents that are the same age point to different locations. Only recent rocks point to the current north magnetic pole.

Where do recent rocks point towards on earth?

[ "north magnetic pole", "equator", "space", "south magnetic pole" ]

0

734

What type of cell function relies on microfilaments, which are the actin components of the cytoskeleton?

[ "muscle", "skin cells", "neurons", "nephrons" ]

0

735

Population Growth The two simplest models of population growth use deterministic equations (equations that do not account for random events) to describe the rate of change in the size of a population over time. The first of these models, exponential growth, describes theoretical populations that increase in numbers without any limits to their growth. The second model, logistic growth, introduces limits to reproductive growth that become more intense as the population size increases. Neither model adequately describes natural populations, but they provide points of comparison. Exponential Growth Charles Darwin, in developing his theory of natural selection, was influenced by the English clergyman Thomas Malthus. Malthus published his book in 1798 stating that populations with abundant natural resources grow very rapidly; however, they limit further growth by depleting their resources. The early pattern of accelerating population size is called exponential growth. The best example of exponential growth in organisms is seen in bacteria. Bacteria are prokaryotes that reproduce largely by binary fission. This division takes about an hour for many bacterial species. If 1000 bacteria are placed in a large flask with an abundant supply of nutrients (so the nutrients will not become quickly depleted), the number of bacteria will have doubled from 1000 to 2000 after just an hour. In another hour, each of the 2000 bacteria will divide, producing 4000 bacteria. After the third hour, there should be 8000 bacteria in the flask. The important concept of exponential growth is that the growth rate—the number of organisms added in each reproductive generation—is itself increasing; that is, the.

The two simplest models of population growth use what to describe the rate of change in the size of a population over time?

[ "deterministic equations", "analogous equations", "predestination equations", "wave function" ]

0

736

Dissociation is the separation of ions that occurs when a solid ionic compound dissolves.

What is the separation of ions that occurs when a solid ionic compound dissolves?

[ "decomposition", "combustion", "dissociation", "inflammation" ]

2

737

Paints can be both toxic and flammable. Paints may spill on the ground or be thrown improperly in the trash.

What do charged particles in motion generate?

[ "gravitational fields", "fission", "electricity", "magnetic fields" ]

3

738

Hydrogen bonding. Hydrogen bonding forms between a highly electronegative oxygen atom or a nitrogen atom and a hydrogen atom attached to another oxygen atom or a nitrogen atom, such as those found in polar amino acid side chains. Hydrogen bonding (as well as ionic attractions) is extremely important in both the intra- and intermolecular interactions of proteins (part (b) of http://catalog. flatworldknowledge. com/bookhub/reader/2547 - gob-ch18_s04_s01_f05). Disulfide linkages. Two cysteine amino acid units may be brought close together as the protein molecule folds. Subsequent oxidation and linkage of the sulfur atoms in the highly reactive sulfhydryl (SH) groups leads to the formation of cystine (part (c) ofhttp://catalog. flatworldknowledge. com/bookhub/reader/2547 - gob-ch18_s04_s01_f05). Intrachain disulfide linkages are found in many proteins, including insulin (yellow bars in http://catalog. flatworldknowledge. com/bookhub/reader/2547 - gob-ch18_s04_s01_f01) and have a strong stabilizing effect on the tertiary structure.

What bonding is formed in polar amino acid side chains?

[ "helium bonding", "hydrogen bonding", "calcium bonding", "carbon bonding" ]

1

739

Geologists study earthquake waves to “see” Earth's interior. Waves of energy radiate out from an earthquake’s focus. These waves are called seismic waves ( Figure below ). Seismic waves go different speeds through different materials. They change speed when they go from one type of material to another. This causes them to bend. Some seismic waves do not travel through liquids or gases. They just stop. Scientists use information from seismic waves to understand what makes up the Earth’s interior.

What is the name for the energy waves that radiate out from the center of an earthquake?

[ "deep waves", "seismic waves", "particle waves", "volcanic waves" ]

1

740

43.5 Human Pregnancy and Birth Human pregnancy begins with fertilization of an egg and proceeds through the three trimesters of gestation. The labor process has three stages (contractions, delivery of the fetus, expulsion of the placenta), each propelled by hormones. The first trimester lays down the basic structures of the body, including the limb buds, heart, eyes, and the liver. The second trimester continues the development of all of the organs and systems. The third trimester exhibits the greatest growth of the fetus and culminates in labor and delivery. Prevention of a pregnancy can be accomplished through a variety of methods including barriers, hormones, or other means. Assisted reproductive technologies may help individuals who have infertility problems.

During a human pregnancy, which trimester exhibits the greatest growth of the fetus and culminates in labor and delivery?

[ "second trimester", "first trimester", "third trimester", "fourth trimester" ]

2

741

Ecologists study ecosystems at every level, from the individual organism to the whole ecosystem and biosphere. They can ask different types of questions at each level. Examples of these questions are given in Table below , using the zebra ( Equus zebra ) as an example.

What do ecologists study at every level?

[ "ecosystems", "taxonomy", "solar system", "plants" ]

0

742

The main shaft of the penis is covered by relatively thick what?

[ "bone", "skin", "collagen", "cellulose" ]

1

743

The broadest category in the Linnaean system is the kingdom . Figure above shows the Animal Kingdom because Homo sapiens belongs to that kingdom. Other kingdoms include the Plant Kingdom, Fungus Kingdom, and Protist Kingdom.

What is the broadest category in the linnaean system?

[ "phylum", "class", "kingdom", "domain" ]

2

744

Most chemical reactions within organisms would be impossible under the normal conditions within cell. For example, the body temperature of most organisms is too low for reactions to occur quickly enough to carry out life processes. Reactants may also be present in such low concentrations that it is unlikely they will meet and collide. Therefore, the rate of most biochemical reactions must be increased by a catalyst. A catalyst is a chemical that speeds up chemical reactions. In organisms, catalysts are called enzymes .

Reactants may also be present in such low concentrations that it is unlikely they will meet and do what?

[ "collide", "explode", "depart", "melt" ]

0

745

Insects range in length from less than a millimeter to about the length of your arm. They can be found in most habitats, but they are mainly terrestrial. Many can fly, so they are also aerial. Like other arthropods, insects have a head, thorax, and abdomen. They have a wide variety of appendages, including six legs attached to the thorax.

The three main body segments of an arthropod are head, thorax, and what?

[ "abdomen", "tail", "legs", "gluteus" ]

0

746

This Concept deals with some Earth basics. Earth is a planet and has the characteristics of a planet. Like other planets, it is nearly round. This is because it has enough mass for its gravity to pull material into a round shape. Earth's gravity has also pulled in small objects, like asteroids. So the planet's orbit is cleared. Earth rotates on its axis and revolves around its star. As a result of its rotation, Earth has a day-night cycle. The tilt of its axis creates the seasons. Earth has layers from crust to mantle to core. The core is divided into a liquid outer core and a solid inner core. The liquid outer core has convection, which generates the magnetic field. The mantle is solid rock. The crust has two major types: continental and oceanic. The crust and uppermost mantle make up the lithosphere. Beneath the lithosphere is the asthenosphere. The lithosphere is brittle and will break. The asthenosphere can flow.

What is the term for what the earth rotates on?

[ "axis", "tip", "compass", "radius" ]

0

747

What is the end product of glycolysis?

[ "hydrolysis", "fructose", "gluclose", "pyruvate" ]

3

748

A vector is any quantity that has magnitude and direction. A scalar is any quantity that has magnitude but no direction. Displacement and velocity are vectors, whereas distance and speed are scalars. In one-dimensional motion, direction is specified by a plus or minus sign to signify left or right, up or down, and the like.

A vector is any quantity that has magnitude and what?

[ "direction", "length", "latitude", "longitude" ]

0

749

Mineral Storage, Energy Storage, and Hematopoiesis On a metabolic level, bone tissue performs several critical functions. For one, the bone matrix acts as a reservoir for a number of minerals important to the functioning of the body, especially calcium, and phosphorus. These minerals, incorporated into bone tissue, can be released back into the bloodstream to maintain levels needed to support physiological processes. Calcium ions, for example, are essential for muscle contractions and controlling the flow of other ions involved in the transmission of nerve impulses. Bone also serves as a site for fat storage and blood cell production. The softer connective tissue that fills the interior of most bone is referred to as bone marrow (Figure 6.5). There are two types of bone marrow: yellow marrow and red marrow. Yellow marrow contains adipose tissue; the triglycerides stored in the adipocytes of the tissue can serve as a source of.

The softer connective tissue that fills the interior of most bone is referred to as what?

[ "solid marrow", "liquid marrow", "attached marrow", "bone marrow" ]

3

750

What is stored mainly in liver and muscle cells by humans and other vertebrates?

[ "glycogen", "amylopectin", "glucose", "protein" ]

0

751

Pedalfer is the soil common in deciduous forests. Pedalfer is dark brown and fertile.

What soil is common in deciduous forests?

[ "pedalfer", "sandy soil", "loam", "xerophyte" ]

0

752

Ammeters and voltmeters are cleverly designed for the way they are used. Ammeters measure the current of a circuit, and voltmeters measure the voltage drop across a resistor. It is important in the design and use of these meters that they don't change the circuit in such a way as to influence the readings. While both types of meters are technically resistors, they are specifically designed to make their readings without changing the circuit itself.

What do voltmeters measure across a resistor?

[ "amplitude", "the vibration drop", "the voltage drop", "energy loss" ]

2

753

Cardiac muscle is found only in the walls of the heart. When cardiac muscle contracts, the heart beats and pumps blood. Cardiac muscle contains a great many mitochondria, which produce ATP for energy. This helps the heart resist fatigue. Contractions of cardiac muscle are involuntary, like those of smooth muscle. Cardiac muscle, like skeletal muscle, is arranged in bundles, so it appears striated , or striped.

Cardiac muscle is found only in which part of the heart?

[ "the ridges", "the bottom", "the walls", "the left side" ]

2

754

Safety precautions are in place to help prevent accidents. Always wear personal protective equipment such as goggles and gloves when recommended to do so by your teacher.

Wearing personal protective equipment such as goggles and gloves during an experiment is an example of what?

[ "office politics", "safety precaution", "pollution precaution", "lab organization" ]

1

755

When the pH of a solution is known, the concentration of the hydrogen ion can be calculated. The inverse of the logarithm (or antilog) is the 10 x key on a calculator.

The concentration of the hydrogen ion in a solution can be calculated when what is known?

[ "velocity", "ph", "temperature", "pressure" ]

1

756

White blood cells also make chemicals that cause a fever. A fever is a higher-than-normal body temperature. Normal human body temperature is 98.6°F (37°C). Most bacteria and viruses that infect people reproduce fastest at this temperature. When the temperature is higher, the pathogens cannot reproduce as fast, so the body raises the temperature to kill them. A fever also causes the immune system to make more white blood cells. In these ways, a fever helps the body fight infection.

A fever also causes the immune system to make more of what?

[ "insulin", "white blood cells", "urea", "red blood cells" ]

1

757

Vascular plants also have roots, stems, and leaves.

Vascular plants all have roots, stems, and what?

[ "leaves", "flowers", "beans", "fruits" ]

0

758

In an aqueous solution, what is the solvent?

[ "oil", "water", "any liquid", "saltwater" ]

1

759

Scientists think that protists are the oldest eukaryotes. If so, they must have evolved from prokaryotes. How did this happen? How did cells without organelles acquire them? What was the origin of mitochondria, chloroplasts, and other organelles?.

What do scientists think to be the oldest eukaryotes?

[ "ciliate", "protists", "arthropods", "bivalves" ]

1

760

Figure 8.7 Bones of the Wrist and Hand The eight carpal bones form the base of the hand. These are arranged into proximal and distal rows of four bones each. The metacarpal bones form the palm of the hand. The thumb and fingers consist of the phalanx bones.

Carpal, metacarpal and phalanx bones comprise what part of the body?

[ "foot", "pelvis", "thumb", "hand" ]

3

761

The first seed plants formed seeds in cones. Cones are made up of overlapping scales, which are modified leaves (see Figure below ). Male cones contain pollen, and female cones contain eggs. Seeds also develop in female cones. Modern seed plants that produce seeds in cones are called gymnosperms .

How did the first seed plants form seeds?

[ "in stems", "in leaves", "in cones", "in folds" ]

2

762

High power microscopic photo of the upper part of a Winter Jasmine leaf. Viewed under a microscope many green chloroplasts are visible.

What green cell structures of a leaf are visible under a high power microscope?

[ "chloroplasts", "fibroblasts", "golgi apparatus", "veins" ]

0

763

The reaction rate indicates how fast the reaction proceeds.

What indicates the speed at which a reaction proceeds?

[ "reaction scale", "the transform rate", "the reaction rate", "time zone" ]

2

764

Mediterranean climates are found on the western coasts of continents. The latitudes are between 30° and 45°. The coast of California has a Mediterranean climate. Temperatures are mild and rainfall is moderate. Most of the rain falls in the winter, and summers are dry. To make it through the dry summers, short woody plants are common.

What type of climate does the coast of california have?

[ "rainforest", "tropical", "arctic", "mediterranean" ]

3

765

Figure 11.7 Solutions of nonelectrolytes such as ethanol do not contain dissolved ions and cannot conduct electricity. Solutions of electrolytes contain ions that permit the passage of electricity. The conductivity of an electrolyte solution is related to the strength of the electrolyte.

Solutions of nonelectrolytes such as ethanol do not contain dissolved ions and cannot conduct what?

[ "light", "electricity", "current", "sound" ]

1

766

Most diplomonads and parabasalids are found in what kind of environment?

[ "enzymatic", "acidic", "skeletal", "anaerobic" ]

3

767

Physical properties include the state of matter and its color and odor. For example, oxygen is a colorless, odorless gas. Chlorine is a greenish gas with a strong, sharp odor. Other physical properties include hardness, freezing and boiling points, the ability to dissolve in other substances, and the ability to conduct heat or electricity. These properties are demonstrated in Figure below . Can you think of other physical properties?.

Oxygen is an element in what form of matter?

[ "liquid", "solid", "gas", "plasma" ]

2

768

What do experts estimate is the cause for the extinction of hundreds of species every year?

[ "migration", "human activities", "intraspecies competition", "predation" ]

1

769

Chemistry is the study of matter and the changes that matter can undergo.

What branch of science is concerned with matter and the changes that it can undergo?

[ "chemistry", "geology", "biology", "physiology" ]

0

770

No charge is actually created or destroyed when charges are separated as we have been discussing. Rather, existing charges are moved about. In fact, in all situations the total amount of charge is always constant. This universally obeyed law of nature is called the law of conservation of charge. Law of Conservation of Charge Total charge is constant in any process.

No charge is actually created or destroyed when charges are separated as we have been discussing. rather, existing charges are moved about. in fact, in all situations the total amount of charge is always this?

[ "more", "smaller", "constant", "less" ]

2

771

The plasma membrane contains molecules other than phospholipids, primarily other lipids and proteins. The green molecules in Figure below , for example, are the lipid cholesterol. Molecules of cholesterol help the plasma membrane keep its shape. Many of the proteins in the plasma membrane assist other substances in crossing the membrane.

What type of molecules help the plasma membrane keep its shape?

[ "proteins", "metabolic", "magnesium", "cholesterol" ]

3

772

Energy must constantly be added to an ecosystem for use by organisms. Matter, on the other hand, is continuously recycled through ecosystems.

Unlike matter, which is continuously recycled through ecosystems, what must constantly be added to an ecosystem for use by organisms?

[ "carbon", "fuel", "energy", "hydrogen" ]

2

773

Ocean water is an example of a liquid. A liquid is matter that has a fixed volume but not a fixed shape. Instead, a liquid takes the shape of its container. If the volume of a liquid is less than the volume of its container, the top surface will be exposed to the air, like the oil in the bottles in Figure below .

What form of matter has a fixed volume but not a fixed shape?

[ "liquid", "mixture", "solid", "gas" ]

0

774

6.5 | Fractures: Bone Repair By the end of this section, you will be able to: • Differentiate among the different types of fractures • Describe the steps involved in bone repair A fracture is a broken bone. It will heal whether or not a physician resets it in its anatomical position. If the bone is not reset correctly, the healing process will keep the bone in its deformed position. When a broken bone is manipulated and set into its natural position without surgery, the procedure is called a closed reduction. Open reduction requires surgery to expose the fracture and reset the bone. While some fractures can be minor, others are quite severe and result in grave complications. For example, a fractured diaphysis of the femur has the potential to release fat globules into the bloodstream. These can become lodged in the capillary beds of the lungs, leading to respiratory distress and if not treated quickly, death.

Why is closed reduction simpler than open reduction in bone repair?

[ "no treatment needed", "no pain pills needed", "no surgery needed", "no medicine needed" ]

2

775

What do methanogens act as in sewage treatment plants?

[ "fertilizers", "killers", "creators", "as decomposers" ]

3

776

Figure 45.9 When resources are unlimited, populations exhibit exponential growth, resulting in a J-shaped curve. When resources are limited, populations exhibit logistic growth. In logistic growth, population expansion decreases as resources become scarce, and it levels off when the carrying capacity of the environment is reached, resulting in an S-shaped curve.

When resources are limited, populations exhibit what type of growth?

[ "efficient growth", "logistic growth", "component growth", "lasting growth" ]

1

777

35.3 The Central Nervous System The vertebrate central nervous system contains the brain and the spinal cord, which are covered and protected by three meninges. The brain contains structurally and functionally defined regions. In mammals, these include the cortex (which can be broken down into four primary functional lobes: frontal, temporal, occipital, and parietal), basal ganglia, thalamus, hypothalamus, limbic system, cerebellum, and brainstem—although structures in some of these designations overlap. While functions may be primarily localized to one structure in the brain, most complex functions, like language and sleep, involve neurons in multiple brain regions. The spinal cord is the information superhighway that connects the brain with the rest of the body through its connections with peripheral nerves. It transmits sensory and motor input and also controls motor reflexes.

What protects the brain and spinal cord in the central nervous system?

[ "Flexing", "neutrophils", "dermis", "meninges" ]

3

778

Adding energy to matter gives its atoms or molecules the ability to resist some of the forces holding them together. For example, heating ice to its melting point (0°C) gives its molecules enough energy to move. The ice melts and becomes liquid water. Similarly, heating liquid water to its boiling point (100°C) gives its molecules enough energy to pull apart from one another so they no longer have contact. The liquid water vaporizes and becomes water vapor.

Heating ice to its melting point (0°c) gives its molecules enough energy to do what?

[ "move", "evaporate", "freeze", "settle" ]

0

779

What occur in arteries that can cause heart attacks and strokes?

[ "clots", "toxins", "tumors", "lesions" ]

0

780

Water pollution comes from many sources. One of the biggest sources is runoff. Runoff picks up chemicals such as fertilizer from agricultural fields, lawns, and golf courses. It carries the chemicals to bodies of water. The added nutrients from fertilizer often cause excessive growth of algae, creating algal blooms (see Figure below ). The algae use up oxygen in the water so that other aquatic organisms cannot survive. This has occurred over large areas of the ocean, creating dead zones , where low oxygen levels have killed all ocean life. A very large dead zone exists in the Gulf of Mexico. Measures that can help prevent these problems include cutting down on fertilizer use. Preserving wetlands also helps because wetlands filter runoff water.

The added nutrients from fertilizer often cause excessive growth of what organism?

[ "mushrooms", "sediments", "crustaceans", "algae" ]

3

781

As decibel levels get higher, sound waves have greater intensity and sounds are louder. For every 10-decibel increase in the intensity of sound, loudness is 10 times greater.

An increase in what levels results in sound waves that are louder and of greater intensity?

[ "radiation levels", "heat levels", "decibel levels", "height levels" ]

2

782

Two plates may slide past each other in opposite directions. This is called a transform plate boundary . The plates meet at a transform fault . As you might imagine, plates do not slide past each other easily. These plate boundaries experience massive earthquakes. The world’s best known transform fault is the San Andreas Fault in California ( Figure below ). At this fault, the Pacific and North American plates grind past each other. Transform plate boundaries are common as offsets along mid-ocean ridges. They are very small compared to transform faults on land.

What is it called when two plates slide past each other in opposite directions?

[ "transform plate boundary", "transformation", "plate divergence", "tectonic movement" ]

0

783

Friction occurs because no surface is perfectly smooth.

What force occurs because no surface is perfectly smooth?

[ "vibration", "friction", "gravity", "tension" ]

1

784

Lymph capillaries collect fluid that leaks out from blood capillaries.

What structure collect fluid that leaks out from blood capillaries?

[ "pulmonary capillaries", "lymph capillaries", "alveoli", "varicose veins" ]

1

785

Neptune is shown in Figure below . It is the eighth planet from the Sun. Neptune is so far away you need a telescope to see it from Earth. Neptune is the most distant planet in our solar system. It is nearly 4.5 billion kilometers (2.8 billion miles) from the Sun. One orbit around the Sun takes Neptune 165 Earth years.

What is the eighth planet from our sun?

[ "mars", "uranus", "earth", "neptune" ]

3

786

Prokaryotic cells are cells without a nucleus. The DNA in prokaryotic cells is in the cytoplasm rather than enclosed within a nuclear membrane. Prokaryotic cells are found in single-celled organisms, such as bacteria, like the one shown in Figure below . Organisms with prokaryotic cells are called prokaryotes . They were the first type of organisms to evolve and are still the most common organisms today.

Where is dna located in prokaryotic cells?

[ "ribosomes", "mitochondria", "cytoskeleton", "cytoplasm" ]

3

787

Water’s Solvent Properties Since water is a polar molecule with slightly positive and slightly negative charges, ions and polar molecules can readily dissolve in it. Therefore, water is referred to as a solvent, a substance capable of dissolving other polar molecules and ionic compounds. The charges associated with these molecules will form hydrogen bonds with water, surrounding the particle with water molecules. This is referred to as a sphere of hydration, or a hydration shell, as illustrated in Figure 2.15 and serves to keep the particles separated or dispersed in the water. When ionic compounds are added to water, the individual ions react with the polar regions of the water molecules and their ionic bonds are disrupted in the process of dissociation. Dissociation occurs when atoms or groups of atoms break off from molecules and form ions. Consider table salt (NaCl, or sodium chloride): when NaCl crystals are added to water, the molecules of NaCl dissociate into Na+ and Cl– ions, and spheres of hydration form around the ions, illustrated in Figure 2.15. The positively charged sodium ion is surrounded by the partially negative charge of the water molecule’s oxygen. The negatively charged chloride ion is surrounded by the partially positive charge of the hydrogen on the water molecule.

Water is considered a what since it is a polar molecule with slightly positive and slightly negative charges, so ions and polar molecules can readily dissolve in it?

[ "osmotic", "solute", "pigment", "solvent" ]

3

788

The pressure inside a container is dependent on the amount of gas inside the container. If the basketball does not bounce high enough, the official could remedy the situation by using a hand pump and adding more air to the ball. Conversely, if it bounces too high, he could let some air out of the ball.

The pressure inside a container is dependent on the amount of what inside the container?

[ "emissions", "air", "gas", "liquids" ]

2

789

Some seed plants evolved another major adaptation. This was the formation of seeds in flowers. Flowers are plant structures that contain male and/or female reproductive organs.

What are plant structures that contain male and/or female reproductive organs?

[ "leaves", "stems", "flowers", "roots" ]

2

790

Each species has a particular way of making a living. This is called its niche . You can see the niche of a lion in Figure below . A lion makes its living by hunting and eating other animals. Each species also has a certain place where it is best suited to live. This is called its habitat . The lion’s habitat is a grassland. Why is a lion better off in a grassland than in a forest?.

Each species has a particular way of making a living which is called its what?

[ "life-cycle", "system", "habit", "niche" ]

3

791

One thing to note about equilibrium is that the reactions do not stop; both the forward reaction and the reverse reaction continue to occur. They both occur at the same rate, so any overall change by one reaction is cancelled by the reverse reaction. We say that chemical equilibrium is dynamic, rather than static. Also, because both reactions are occurring simultaneously, the equilibrium can be written backward. For example, representing an equilibrium as.

Both the forward reaction and the reverse reaction continue to occur, so chemical equilibrium is said to be what, rather than static?

[ "fluid", "dynamic", "abrasive", "stable" ]

1

792

The Lymphatic System Lymph is the watery fluid that bathes tissues and organs and contains protective white blood cells but does not contain erythrocytes. Lymph moves about the body through the lymphatic system, which is made up of vessels, lymph ducts, lymph glands, and organs, such as tonsils, adenoids, thymus, and spleen. Although the immune system is characterized by circulating cells throughout the body, the regulation, maturation, and intercommunication of immune factors occur at specific sites. The blood circulates immune cells, proteins, and other factors through the body. Approximately 0.1 percent of all cells in the blood are leukocytes, which include monocytes (the precursor of macrophages) and lymphocytes. Most cells in the blood are red blood cells. Cells of the immune system can travel between the distinct lymphatic and blood circulatory systems, which are separated by interstitial space, by a process called extravasation (passing through to surrounding tissue). Recall that cells of the immune system originate from stem cells in the bone marrow. B cell maturation occurs in the bone marrow, whereas progenitor cells migrate from the bone marrow and develop and mature into naïve T cells in the organ called the thymus. On maturation, T and B lymphocytes circulate to various destinations. Lymph nodes scattered throughout the body house large populations of T and B cells, dendritic cells, and macrophages (Figure 17.19). Lymph gathers antigens as it drains from tissues. These antigens then are filtered through lymph nodes before the lymph is returned to circulation. APCs in the lymph nodes capture and process antigens and inform nearby lymphocytes about potential pathogens.

What is the watery fluid that bathes tissues and organs and contains protective white blood cells but does not contain erythrocytes?

[ "lymph", "stomach", "secretion", "basil" ]

0

793

Adult tunicates are barrel-shaped. They have two openings that siphon water into and out of the body. The flow of water provides food for filter feeding. Tunicates reproduce sexually. Each individual produces both male and female gametes. However, they avoid self-fertilization. Tunicates can also reproduce asexually by budding.

How many openings do adult tunicates have that siphon water in and out of the body?

[ "three", "two", "four", "one" ]

1

794

The combined forces acting on an object are called the net force. When forces act in opposite directions, they are subtracted to yield the net force. When they act in the same direction, they are added to yield the net force.

What is the term for the combined forces acting on an object?

[ "total impact", "net force", "critical force", "blunt force" ]

1

795

The first stage of photosynthesis is called the light reactions. During this stage, light is absorbed and transformed to chemical energy in the bonds of NADPH and ATP. You can follow the process in the Figure below as you read about it below.

What is the name of the first stage of photosynthesis?

[ "light reactions", "consumption", "absorption", "contamination" ]

0

796

Birds are endothermic tetrapod vertebrates. They are bipedal, which means they walk on two legs. Birds also lay amniotic eggs, and the eggs have hard, calcium carbonate shells. Although birds are the most recent class of vertebrates to evolve, they are now the most numerous vertebrates on Earth. Why have birds been so successful? What traits allowed them to increase and diversify so rapidly?.

What are endothermic tetrapod vertebrates most commonly called?

[ "mammals", "birds", "insects", "reptiles" ]

1

797

It literally jumps by way of a chemical transmitter. Notice the two cells are not connected, but separated by a small gap. The synapse. The space between a neuron and the next cell.

What is the space between a neuron and the next cell?

[ "the synapse", "dendritic gap", "neurotransmitter passage", "cell divide" ]

0

798

In the Figure below , we see the structures of some common classes of lipids. Free fatty acids are carboxylic acids that contain long hydrocarbon chains. Saturated fatty acids are alkanes with a single carboxylic acid, whereas unsaturated fatty acids contain one or more C-C double bonds. Fatty acids often form esters with one of the alcohol functional groups on glycerol , a three carbon chain in which each carbon is bonded to one OH group. Triglycerides are common structures, in which all three of these OH groups are esterified with a fatty acid. The three fatty acids in a triglyceride may be the same or different. Another common structure is a phospholipid, in which two of the alcohols in glycerol form esters with fatty acids, and the third is connected to a very polar phosphorus-containing group.

Free fatty acids are carboxylic acids that contain long chains of what?

[ "hydrocarbons", "vapors", "particles", "lipds" ]

0

799

Macronutrients are nutrients the body needs in relatively large amounts. They include carbohydrates, proteins, lipids, and water.

What do you call nutrients that your body needs in fairly large amounts?

[ "antioxidants", "macronutrients", "super foods", "B-complex" ]

1