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Like all tetrapods except birds and mammals, frogs possess a heart with what structure? | eight chambers | One Chamber | four chambers | three chambers | Adult frogs are characterized by long hind legs, a short body, webbed finger-like parts, and the lack of a tail. They also have a three-chambered heart, as do all tetrapods except birds and mammals. Most frogs live part of the time in water and part of the time on land. They move easily on land by jumping or climbing. To become great jumpers, frogs evolved long hind legs and long ankle bones. They also have a short backbone with only ten vertebrae. Frog and toad skin hangs loosely on the body, and skin texture can be smooth, warty, or folded. |
Energy is the capacity to do work or to produce what? | humidity | vibration | light | heat | Energy is the capacity to do work or to produce heat. |
In mammals, sound waves are collected by the external, cartilaginous part of the ear called the pinna, then travel through the auditory canal and cause vibration of the thin diaphragm called the tympanum or this? | head drum | speaker drum | microphone drum | ear drum | Reception of Sound In mammals, sound waves are collected by the external, cartilaginous part of the ear called the pinna, then travel through the auditory canal and cause vibration of the thin diaphragm called the tympanum or ear drum, the innermost part of the outer ear (illustrated in Figure 36.13). Interior to the tympanum is the middle ear. The middle ear holds three small bones called the ossicles, which transfer energy from the moving tympanum to the inner ear. The three ossicles are the malleus (also known as the hammer), the incus (the anvil), and stapes (the stirrup). The aptly named stapes looks very much like a stirrup. The three ossicles are unique to mammals, and each plays a role in hearing. The malleus attaches at three points to the interior surface of the tympanic membrane. The incus attaches the malleus to the stapes. In humans, the stapes is not long enough to reach the tympanum. If we did not have the malleus and the incus, then the vibrations of the tympanum would never reach the inner ear. These bones also function to collect force and amplify sounds. The ear ossicles are homologous to bones in a fish mouth: the bones that support gills in fish are thought to be adapted for use in the vertebrate ear over evolutionary time. Many animals (frogs, reptiles, and birds, for example) use the stapes of the middle ear to transmit vibrations to the middle ear. |
Unlike ionic compounds, covalent compounds do not have freely moving what? | Nuclei. | neutrons | atoms | electrons | Unlike ionic compounds, covalent compounds do not have freely moving electrons, so they cannot conduct electricity. |
How do seed plants benefit from herbivores? | rainfall of seeds | radiation of seeds | consumption of seeds | dispersal of seeds | Herbivory has been used by seed plants for their own benefit in a display of mutualistic relationships. The dispersal of fruit by animals is the most striking example. The plant offers to the herbivore a nutritious source of food in return for spreading the plant’s genetic material to a wider area. An extreme example of collaboration between an animal and a plant is the case of acacia trees and ants. The trees support the insects with shelter and food. In return, ants discourage herbivores, both invertebrates and vertebrates, by stinging and attacking leaf-eating insects. |
What is the process in which cells make proteins called? | gas synthesis | factor synthesis | light synthesis | protein synthesis | The process in which cells make proteins is called protein synthesis . It actually consists of two processes: transcription and translation . Transcription takes place in the nucleus. It uses DNA as a template to make an RNA molecule. RNA then leaves the nucleus and goes to a ribosome in the cytoplasm, where translation occurs. Translation reads the genetic code in mRNA and makes a protein. |
How do you decrease errors in an experiment? | decrease measurements | write about it | ask God | take many measurements | Scientists make many measurements during experiments. Humans and equipment can make mistakes. Errors are often unavoidable. This is called experimental error . Errors may be due to the equipment being used. In this case, the numbers may be always skewed in one direction. For example, a scale may always measure one-half of an ounce high. People can also make errors. A measurement may not be made precisely. For example, a stopwatch may be stopped too soon or too late. But probably not always in the same direction. To correct for this, many measurements are taken. The measurements are then averaged. Experiments always have a margin of error associated with them. |
What term describes scientists who debate the origin of the earliest plants? | protobotanists | specialists | archaebotanists | paleobotanists | Evolution of Angiosperms Undisputed fossil records place the massive appearance and diversification of angiosperms in the middle to late Mesozoic era. Angiosperms (“seed in a vessel”) produce a flower containing male and/or female reproductive structures. Fossil evidence (Figure 26.6) indicates that flowering plants first appeared in the Lower Cretaceous, about 125 million years ago, and were rapidly diversifying by the Middle Cretaceous, about 100 million years ago. Earlier traces of angiosperms are scarce. Fossilized pollen recovered from Jurassic geological material has been attributed to angiosperms. A few early Cretaceous rocks show clear imprints of leaves resembling angiosperm leaves. By the mid-Cretaceous, a staggering number of diverse flowering plants crowd the fossil record. The same geological period is also marked by the appearance of many modern groups of insects, including pollinating insects that played a key role in ecology and the evolution of flowering plants. Although several hypotheses have been offered to explain this sudden profusion and variety of flowering plants, none have garnered the consensus of paleobotanists (scientists who study ancient plants). New data in comparative genomics and paleobotany have, however, shed some light on the evolution of angiosperms. Rather than being derived from gymnosperms, angiosperms form a sister clade (a species and its descendents) that developed in parallel with the gymnosperms. The two innovative structures of flowers and fruit represent an improved reproductive strategy that served to protect the embryo, while increasing genetic variability and range. Paleobotanists debate whether angiosperms evolved from small woody bushes, or were basal angiosperms related to tropical grasses. Both views draw support from cladistics studies, and the so-called woody magnoliid hypothesis—which proposes that the early ancestors of angiosperms were shrubs—also offers molecular biological evidence. |
What anatomical system is made up of neurons and glia? | digestive system | reproductive system | lymphatic system | nervous system | CHAPTER SUMMARY 35.1 Neurons and Glial Cells The nervous system is made up of neurons and glia. Neurons are specialized cells that are capable of sending electrical as well as chemical signals. Most neurons contain dendrites, which receive these signals, and axons that send signals to other neurons or tissues. There are four main types of neurons: unipolar, bipolar, multipolar, and pseudounipolar neurons. Glia are non-neuronal cells in the nervous system that support neuronal development and signaling. There are several types of glia that serve different functions. |
What term describes the overall ability of an animal to survive and produce offspring? | abilities | change | evolution | fitness | Animal communication, like most other animal behaviors, increases the ability to survive and have offspring. This is known as fitness. Communication increases fitness by helping animals find food, defend themselves from predators, mate, and care for offspring. |
Production of abnormal white blood cells occurs in what cancer, which is the most common form in children? | Bone | Brain | Breast | leukemia | Cancer can also be found in children. But childhood cancer is rare. Leukemia is the main type of cancer in children. It makes up about one third of all childhood cancers. It happens when the body makes abnormal white blood cells. |
How is the energy of an atomic orbital affected as the principal quantum number increases? | It triples | it decreases | It doubles | it increases | Orbital Energies and Atomic Structure The energy of atomic orbitals increases as the principal quantum number, n, increases. In any atom with two or more electrons, the repulsion between the electrons makes energies of subshells with different values of l differ so that the energy of the orbitals increases within a shell in the order s < p < d < f. Figure 6.25 depicts how these two trends in increasing energy relate. The 1s orbital at the bottom of the diagram is the orbital with electrons of lowest energy. The energy increases as we move up to the 2s and then 2p, 3s, and 3p orbitals, showing that the increasing n value has more influence on energy than the increasing l value for small atoms. However, this pattern does not hold for larger atoms. The 3d orbital is higher in energy than the 4s orbital. Such overlaps continue to occur frequently as we move up the chart. |
During the typical human female ovulation cycles, how many eggs are released? | three | four | two | one | The Zygote Recall that at the point of fertilization, the oocyte has not yet completed meiosis; all secondary oocytes remain arrested in metaphase of meiosis II until fertilization. Only upon fertilization does the oocyte complete meiosis. The unneeded complement of genetic material that results is stored in a second polar body that is eventually ejected. At this moment, the oocyte has become an ovum, the female haploid gamete. The two haploid nuclei derived from the sperm and oocyte and contained within the egg are referred to as pronuclei. They decondense, expand, and replicate their DNA in preparation for mitosis. The pronuclei then migrate toward each other, their nuclear envelopes disintegrate, and the male- and femalederived genetic material intermingles. This step completes the process of fertilization and results in a single-celled diploid zygote with all the genetic instructions it needs to develop into a human. Most of the time, a woman releases a single egg during an ovulation cycle. However, in approximately 1 percent of ovulation cycles, two eggs are released and both are fertilized. Two zygotes form, implant, and develop, resulting in the. |
Spores are the basic reproductive units of what organism? | tropical plants | mushrooms | yeast | fungi | Specialized structures for reproduction: One example is a fruiting body. Just like a fruit is involved in the reproduction of a fruiting plant, a fruiting body is involved in the reproduction of a fungus. A mushroom is a fruiting body , which is the part of the fungus that produces spores ( Figure below ). The spores are the basic reproductive units of fungi. The mycelium remains hidden until it develops one or more fruiting bodies. |
During diastole, what happens to the elastic walls of the arteries? | they evolve | they expand | they become hardened | they snap back | |
Blood pressure is significantly affected by what physical force? | density | mass | volume | gravity | |
An electormagnet is a piece of iron inside a? | reactor | copper core | tunnel | solenoid | An electormagnet is a piece of iron inside a solenoid. |
What term describes motion that repeats itself at regular time intervals, such as exhibited by a vibrating guitar string? | apparent motion | gravitational pull | specific speed | periodic motion | When you pluck a guitar string, the resulting sound has a steady tone and lasts a long time. Each successive vibration of the string takes the same time as the previous one. We define periodic motion to be a motion that repeats itself at regular time intervals, such as exhibited by the guitar string or by an object on a spring moving up and down. The time to complete one oscillation remains constant and is called the period T . Its units are usually seconds, but may be any convenient unit of time. The word period refers to the time for some event whether repetitive or not; but we shall be primarily interested in periodic motion, which is by definition repetitive. A concept closely related to period is the frequency of an event. For example, if you get a paycheck twice a month, the frequency of payment is two per month and the period between checks is half a month. Frequency f is defined to be the number of events per unit time. For periodic motion, frequency is the number of oscillations per unit time. The relationship between frequency and period is. |
What form do biofuels take that makes them very useful? | chemical | crystals | solid | liquid | Biofuels are useful because they are liquid. Biofuels can go into a gas tank unlike many other types of alternative energy. |
Most of food's chemical energy ultimately comes from what source? | minerals | plants | air | sunlight | Living things must have chemical energy from food to power life processes. Most of the chemical energy in food comes ultimately from the energy in sunlight. |
The northern spotted owl and the mexican spotted owl inhabit geographically separate locations with different climates and ecosystems. the owl is an example of? | symbiotic species | parallel evolution | biodiversity | allopatric speciation | Figure 18.12 The northern spotted owl and the Mexican spotted owl inhabit geographically separate locations with different climates and ecosystems. The owl is an example of allopatric speciation. (credit "northern spotted owl": modification of work by John and Karen Hollingsworth; credit "Mexican spotted owl": modification of work by Bill Radke). |
Human actions such as plowing, logging, construction and other actions contribute to what kind of erosion? | wind erosion | weathering | flooding | soil erosion | Many human actions make it easier for wind and water to carry away soil. They include plowing, logging, construction, and even some types of recreation. |
Why does the fish odour diminish when you put lemon juice over cooked fish? | due to acidification | due to oxidation | due to evaporation | due to neutralization | Chemistry in Everyday Life Culinary Aspects of Chemistry Cooking is essentially synthetic chemistry that happens to be safe to eat. There are a number of examples of acid-base chemistry in the culinary world. One example is the use of baking soda, or sodium bicarbonate in baking. NaHCO3 is a base. When it reacts with an acid such as lemon juice, buttermilk, or sour cream in a batter, bubbles of carbon dioxide gas are formed from decomposition of the resulting carbonic acid, and the batter “rises. ” Baking powder is a combination of sodium bicarbonate, and one or more acid salts that react when the two chemicals come in contact with water in the batter. Many people like to put lemon juice or vinegar, both of which are acids, on cooked fish (Figure 14.15). It turns out that fish have volatile amines (bases) in their systems, which are neutralized by the acids to yield involatile ammonium salts. This reduces the odor of the fish, and also adds a “sour” taste that we seem to enjoy. |
When additional water is added to an aqueous solution, what happens to the concentration of that solution? | increases | doubles | no change | decreases | When additional water is added to an aqueous solution, the concentration of that solution decreases. This is because the number of moles of the solute does not change, while the volume of the solution increases. We can set up an equality between the moles of the solute before the dilution (1) and the moles of the solute after the dilution (2). |
How many chambers does a mammalian heart have? | three | one | five | four | The four-chambered mammalian heart can pump blood in two different directions. The right side of the heart pumps blood to the lungs to pick up oxygen. The left side of the heart pumps blood containing oxygen to the rest of the body. Because of the dual pumping action of the heart, all of the blood going to body cells is rich in oxygen. |
Meaning a disease that spreads from person to person, what term is synonymous with "contagious"? | noncommunicable | benign | harmless | infectious | Has this ever happened to you? A student sitting next to you in class has a cold. The other student is coughing and sneezing, but you feel fine. Two days later, you come down with a cold, too. Diseases like colds are contagious. Contagious diseases are also called infectious diseases. An infectious disease is a disease that spreads from person to person. |
The common carotid artery gives rise to the external and internal carotid arteries. the external carotid artery remains superficial and gives rise to many arteries of this? | back | chest | stomach | head | Figure 20.26 Arteries Supplying the Head and Neck The common carotid artery gives rise to the external and internal carotid arteries. The external carotid artery remains superficial and gives rise to many arteries of the head. The internal carotid artery first forms the carotid sinus and then reaches the brain via the carotid canal and carotid foramen, emerging into the cranium via the foramen lacerum. The vertebral artery branches from the subclavian artery and passes through the transverse foramen in the cervical vertebrae, entering the base of the skull at the vertebral foramen. The subclavian artery continues toward the arm as the axillary artery. |
What are resources that don't run out? | orbital resources | residual resources | general resources | renewable resources | Renewable resources can be renewed as they are used. An example is timber , which comes from trees. New trees can be planted to replace those that are cut down. Sunlight is a renewable resource. It seems we will never run out of that! What are some other renewable resources?. |
Maintaining a balance inside the body or cells of organisms is known as? | consciousness | ketosis | equanimity | homeostasis | When you are cold, what does your body do to keep warm? You shiver to warm up your body. When you are too warm, you sweat to release heat. When any living organism gets thrown off balance, its body or cells help it return to normal. In other words, living organisms have the ability to keep a stable internal environment. Maintaining a balance inside the body or cells of organisms is known as homeostasis . Like us, many animals have evolved behaviors that control their internal temperature. A lizard may stretch out on a sunny rock to increase its internal temperature, and a bird may fluff its feathers to stay warm ( Figure below ). |
The ability to what is affected by the velocity, or speed, of the water? | hinder | construct | impede | erode | Moving water also picks up and carries particles of soil and rock. The ability to erode is affected by the velocity, or speed, of the water. The size of the eroded particles depends on the velocity of the water. Eventually, the water deposits the materials. As water slows, larger particles are deposited. As the water slows even more, smaller particles are deposited. The graph in Figure below shows how water velocity and particle size influence erosion and deposition. |
What is the process of isolating a specific gene and then making a copy of it for use in gene therapy? | gene copying | attribute cloning | gene treatment | gene cloning | Gene cloning is the process of isolating and making copies of a gene. This is useful for many purposes. For example, gene cloning might be used to isolate and make copies of a normal gene for gene therapy. Gene cloning involves four steps: isolation, ligation, transformation, and selection. You can watch an interactive animation about gene cloning at this link: http://www. teachersdomain. org/asset/biot09_int_geneclone/ . |
The epochs of the universe are known back to very shortly after what 'explosive' event? | major bang | Biggest bang | Explosive bang | big bang | H0 = 20km/s ⋅ Mly. • Explanations of the large-scale characteristics of the universe are intimately tied to particle physics. • The dominance of matter over antimatter and the smoothness of the CMBR are two characteristics that are tied to particle physics. • The epochs of the universe are known back to very shortly after the Big Bang, based on known laws of physics. • The earliest epochs are tied to the unification of forces, with the electroweak epoch being partially understood, the GUT epoch being speculative, and the TOE epoch being highly speculative since it involves an unknown single superforce. • The transition from GUT to electroweak is called spontaneous symmetry breaking. It released energy that caused the inflationary scenario, which in turn explains the smoothness of the CMBR. |
What is the term for a change in an object’s motion, which occurs whenever an object is acted upon by an unbalanced force? | inclination | rotation | compression | acceleration | A change in an object’s motion—such as Xander speeding up on his scooter—is called acceleration . Acceleration occurs whenever an object is acted upon by an unbalanced force. The greater the net force acting on the object, the greater its acceleration will be, but the mass of the object also affects its acceleration. The smaller its mass is, the greater its acceleration for a given amount of force. Newton’s second law of motion summarizes these relationships. According to this law, the acceleration of an object equals the net force acting on it divided by its mass. This can be represented by the equation:. |
All metabolic functions carried out by a prokaryote take place in the plasma membrane or where else? | mitochondrial | extracellular | Shell | cytosol | The bacterium in Figure above is a prokaryote. Prokaryotes are microscopic organisms that have neither a membrane-bound nucleus nor membrane-bound organelles. Some cell biologists consider the term "organelle" to describe membrane-bound structures only, whereas other cell biologists define organelles as discrete structures that have a specialized function. Prokaryotes have ribosomes, which are not surrounded by a membrane but do have a specialized function, and could therefore be considered organelles. All metabolic functions carried out by a prokaryote take place in the plasma membrane or the cytosol. |
How does burning matter affect its mass? | the mass decreases | the mass quadruples | the mass increases | the mass remains the same | Burning and other changes in matter do not destroy matter. The mass of matter is always the same before and after the changes occur. |
What type of stratified deposit is formed where lakes are covered by ice in the winter? | tangles | telomeres | glacier | varves | Several types of stratified deposits form in glacial regions but are not formed directly by the ice. Varves form where lakes are covered by ice in the winter. Dark, fine-grained clays sink to the bottom of the lake in winter. Melting ice in the spring brings running water that deposits lighter colored sands. Each alternating dark/light layer represents one year of deposits. |
Where do greenhouse gases trap heat? | altitude | ground | space | atmosphere | We learned in the previous concept, "Scientific Explanations and Interpretations," that the average global temperature has been on the rise. Scientists know that carbon dioxide is a greenhouse gas . Greenhouse gases trap heat in the atmosphere. This leads us to a question:. |
The hamstrings flex the leg, whereas the quadriceps femoris have what effect? | no effect | contract | stabilize | extend | The hamstrings flex the leg, whereas the quadriceps femoris extend it. |
Many ceramics are composed of what, which are salts containing anions composed of silicon and oxygen? | soils | vinylates | crystals | silicates | At 1600 °C, quartz melts to yield a viscous liquid. When the liquid cools, it does not crystallize readily but usually supercools and forms a glass, also called silica. The SiO4 tetrahedra in glassy silica have a random arrangement characteristic of supercooled liquids, and the glass has some very useful properties. Silica is highly transparent to both visible and ultraviolet light. For this reason, it is important in the manufacture of lamps that give radiation rich in ultraviolet light and in certain optical instruments that operate with ultraviolet light. The coefficient of expansion of silica glass is very low; therefore, rapid temperature changes do not cause it to fracture. CorningWare and other ceramic cookware contain amorphous silica. Silicates are salts containing anions composed of silicon and oxygen. In nearly all silicates, sp3-hybridized silicon atoms occur at the centers of tetrahedra with oxygen at the corners. There is a variation in the silicon-to-oxygen ratio that occurs because silicon-oxygen tetrahedra may exist as discrete, independent units or may share oxygen atoms at corners in a variety of ways. In addition, the presence of a variety of cations gives rise to the large number of silicate minerals. Many ceramics are composed of silicates. By including small amounts of other compounds, it is possible to modify the physical properties of the silicate materials to produce ceramics with useful characteristics. |
Attaching strips of neutral metals that are higher in the activity series can protect a structure from what? | weathering | diffusion | deoxidation | corrosion | Attaching strips of neutral metals that are higher in the activity series can protect a structure from corrosion. |
Weight is a measure of what force pulling down on an object? | motion | light | distortion | gravity | Weight is a measure of the force of gravity pulling down on an object, whereas buoyant force pushes up on an object. Which force is greater determines whether an object sinks or floats. Look at the Figure below . On the left, the object’s weight is the same as the buoyant force acting on it, so the object floats. On the right, the object’s weight is greater than the buoyant force acting on it, so the object sinks. |
What organ absorbs about 90 percent of the water you ingest? | large intestine | skin | lungs | small intestine | Absorption, Feces Formation, and Defecation The small intestine absorbs about 90 percent of the water you ingest (either as liquid or within solid food). The large intestine absorbs most of the remaining water, a process that converts the liquid chyme residue into semisolid feces (“stool”). Feces is composed of undigested food residues, unabsorbed digested substances, millions of bacteria, old epithelial cells from the GI mucosa, inorganic salts, and enough water to let it pass smoothly out of the body. Of every 500 mL (17 ounces) of food residue that enters the cecum each day, about 150 mL (5 ounces) become feces. Feces are eliminated through contractions of the rectal muscles. You help this process by a voluntary procedure called Valsalva’s maneuver, in which you increase intra-abdominal pressure by contracting your diaphragm and abdominal wall muscles, and closing your glottis. The process of defecation begins when mass movements force feces from the colon into the rectum, stretching the rectal wall and provoking the defecation reflex, which eliminates feces from the rectum. This parasympathetic reflex is mediated by the spinal cord. It contracts the sigmoid colon and rectum, relaxes the internal anal sphincter, and initially contracts the external anal sphincter. The presence of feces in the anal canal sends a signal to the brain, which gives you the choice of voluntarily opening the external anal sphincter (defecating) or keeping it temporarily closed. If you decide to delay defecation, it takes a few seconds for the reflex contractions to stop and the rectal walls to relax. The next mass movement will trigger additional defecation reflexes until you defecate. If defecation is delayed for an extended time, additional water is absorbed, making the feces firmer and potentially leading to constipation. On the other hand, if the waste matter moves too quickly through the intestines, not enough water is absorbed, and diarrhea can result. This can be caused by the ingestion of foodborne pathogens. In general, diet, health, and stress determine the frequency of bowel movements. The number of bowel movements varies greatly between individuals, ranging from two or three per day to three or four per week. |
In drosophila, gradients of morphogens encoded by maternal effect genes determine what? | body mass | cell mass | cells axes | body axes | |
What features of a salamander's skin help protect itself from predators ? | thick and impenetrable | camouflaged and thin | slimy and camouflaged | brightly colored and poisonous | Salamanders have developed ways not to be eaten. Most salamanders have brightly colored, poisonous skin. The bold color tells predators not to eat the salamander. Many salamanders have glands on the back of the neck or on the tail that give off a poisonous or bad-tasting liquid. Some species can even shed their tail during an attack and grow a new one later. Some salamanders stand high on its legs and waves its tail to scare away danger. One particular salamander, the ribbed newt, has needle-like rib tips. It can squeeze its muscles to make the rib tips pierce through its skin and into its enemy, telling the predator to stay away, a feature unique among the animal kingdom. |
Precipitation maps show the amount of what in different areas? | geographical variety | population | heat | rainfall | Precipitation maps show the amount of rainfall in different areas. |
What is a germ cell that divides into gametocytes during gametogenesis? | pollenation | cocklebur | gonads | gametogonium | From gametogonium (plural, gametogonia ), male and female gametes develop differently - males by spermatogenesis and females by oogenesis. A gametogonium is a germ cell that divides into gametocytes during gametogenesis. Male gametogonia are called spermatogonia , and female gametogonia are called oogonia . However, the following pattern is common for both oogonia and soermatogonia (chromosome numbers depict human chromosomes):. |
The saguaro doesn't have any leaves to lose water by which process? | propagation | respiration | evaporation | transpiration | The saguaro cactus pictured in Figure below has adapted in all three ways. When it was still a very small plant, just a few inches high, its shallow roots already reached out as much as 2 meters (7 feet) from the base of the stem. By now, its root system is much more widespread. It allows the cactus to gather as much moisture as possible from rare rainfalls. The saguaro doesn't have any leaves to lose water by transpiration. It also has a large, barrel-shaped stem that can store a lot of water. Thorns protect the stem from thirsty animals that might try to get at the water inside. |
What is the most important source of energy on earth? | moon | the earth's core | water | sun | The sunlight that reaches Earth is the planet’s most important source of energy. The energy in sunlight, called solar energy, is electromagnetic energy. This is a form of energy that travels through space in electric and magnetic waves. Solar energy can be used to heat homes and produce electricity in solar cells like those on the roof seen in the Figure below . Sunny areas receive plenty of sunlight to generate electricity, but solar energy may not be practical in areas that are often cloudy. |
What do cyclotrons use to cause particles to move in circular orbits? | mixed field | layers field | occurs field | magnetic field | Figure 33.8 Cyclotrons use a magnetic field to cause particles to move in circular orbits. As the particles pass between the plates of the Ds, the voltage across the gap is oscillated to accelerate them twice in each orbit. |
An example of a variable relating to the ramp is its what? | weight | color | mass | steepness | A: Variables might include factors relating to the ramp or to the object. An example of a variable relating to the ramp is its steepness. An example of a variable relating to the object is the way it moves—it might roll or slide down the ramp. Either of these variables could be manipulated by the researcher, so you could choose one of them for your manipulated variable. |
Deep within the earth what force is so great that a rock behaves like a stretched rubber band? | volcanoes | momentum | magnetism | pressure | The amount of stress on a rock may be greater than the rock’s strength. In that case, the rock will undergo strain or deformation ( Figure below ). Deep within the Earth, the pressure is very great. A rock behaves like a stretched rubber band. When the stress stops, the rock goes back to its original shape. If more stress is applied to the rock, it bends and flows. It does not return to its original shape. Near the surface, if the stress continues, the rock will fracture (rupture) and break. |
What shape is the colony of a volvox cell? | tubular | pyramid | coil-shaped | hollow ball shaped | Volvox Colony. Volvox cells live in a colony shaped like a hollow ball. The cells of the colony may be connected by strands of cytoplasm and can function together. For example, the whole colony can swim from one place to another as one. |
What do puffer fish produce to protect itself? | hormones | teeth | enzymes | venom | This odd-looking creature is a fish called a puffer fish. Like all fish, puffer fish are vertebrates. The puffer fish puffs up by rapidly filling its stretchy stomach with water. The reason? Getting bigger makes the fish seem larger to potential predators. Just to be on the safe side, the puffer fish also produces venom. In fact, it’s the second-most-poisonous vertebrate in the world after the poison dart frog. In this chapter, you’ll learn more about vertebrates such as these. You’ll find out that vertebrates are a diverse and fascinating group of animals. |
What are polymers composed of many sugar building blocks called? | hydrocarbons | monosaccarides | monomers | polysaccharides | |
Most gas molecules in the atmosphere are pulled close to earth’s surface by what force? | traction | weight | light | gravity | Like water in the ocean, air in the atmosphere exerts pressure that increases with depth. Most gas molecules in the atmosphere are pulled close to Earth’s surface by gravity. As a result, air pressure decreases quickly at lower altitudes and then more slowly at higher altitudes. This is illustrated in Figure below . Air pressure is greatest at sea level, where the depth of the atmosphere is greatest. At higher altitudes, the pressure is less because the depth of the atmosphere is less. For example, on top of Mount Everest, the tallest mountain on Earth, air pressure is only about one-third of the pressure at sea level. At such high altitudes, low air pressure makes it hard to breathe and is dangerous to human health. |
Coral reefs and tropical rainforests are ecosystems known for what, contributing greatly to the species in existence on earth? | spontaneous mutation | commensalism | mass migrations | biodiversity | How many species actually exist in the world? No one knows for sure because only a small percentage of them have already been discovered. Estimates range from 5 to 30 million total species currently in existence. Many of them live on coral reefs and in tropical rainforests (see Figure below ). These two ecosystems have some of the greatest biodiversity on the planet. |
Gymnosperms and angiosperms are types of _________ seed plants. | genetic | heritage | extinct | modern | Modern seed plants include gymnosperms and angiosperms. |
Not getting enough calcium may cause what health problem? | diabetes | blindness | arthritis | osteoporosis | Not getting enough minerals can cause health problems. For example, not getting enough calcium may cause osteoporosis. This is a disease in which the bones become porous so they break easily. Getting too much of some minerals can also cause health problems. Many people get too much sodium. Sodium is added to most packaged foods. People often add more sodium to their food by using table salt. Too much sodium has been linked to high blood pressure in some people. |
What is the sequence of elementary steps that together comprise an entire chemical reaction called? | basic reaction | reaction circle | mechanical mechanism | reaction mechanism | The overall balanced equation for a chemical reaction does not always tell us how a reaction actually proceeds. In many cases, the overall reaction takes place in a series of small steps. An elementary step (or elementary reaction) is one step in a series of simple reactions that show the progress of a reaction at the molecular level. In terms of collision theory, each elementary step corresponds to a single collision. A reaction mechanism is the sequence of elementary steps that together comprise an entire chemical reaction. As an analogy, consider the route that you might take while driving to the grocery store. That route may consist of several turns, similar to the elementary steps. The overall reaction specifies only the beginning point (your house) and the final destination (the store), with no information about the specifics in between. |
What is the clear, curved structure that works with the cornea to help focus light at the back of the eye? | iris | pupil | retina | lens | After passing into the eye through the pupil, light passes through the lens. The lens of the eye is a clear, curved structure. Along with the cornea, the lens helps focus light at the back of the eye. This is pictured below ( Figure below ). |
What is the color of the powder of a mineral called? | hue | dye | pigment | streak | Streak is the color of the powder of a mineral. To do a streak test, you scrape the mineral across an unglazed porcelain plate. The plate is harder than many minerals, causing the minerals to leave a streak of powder on the plate. The color of the streak often differs from the color of the larger mineral sample ( Figure below ). Yellow-gold pyrite has a blackish streak. This blackish streak tells you that the mineral is not gold, because gold has a gold-colored streak. |
What part of the plant anchors it into the soil? | leaves | stems | buds | roots | |
Evolution happens because of what? | natural process | natural resources | natural change | natural selection | Evolution happens because of natural selection . Good traits become more common in a population. Bad traits become less common. The deer mouse, species Peromyscus maniculatus gives an example of evolution by natural selection. In Nebraska, this mouse is typically brown. But in places where glaciers dropped lighter sand over the darker soil, the mice are light. Why? Because predators could more easily spot the dark mice on light sand. The lighter mice were more likely to survive and have offspring. Natural selection favored the light mice. Over time, the population became light colored. Enough changes may take place over time that the two types of mice become different species. |
The nephron is the functional unit of what pair of organs? | ribs | lungs | eyes | kidneys | Figure 41.6 The nephron is the functional unit of the kidney. The glomerulus and convoluted tubules are located in the kidney cortex, while collecting ducts are located in the pyramids of the medulla. (credit: modification of work by NIDDK). |
Nonshivering thermogenesis, which involves the breakdown of brown adipose tissue, is a special methods newborns have for what purpose? | moving heat | losing heat | harnessing heat | generating heat | Thermoregulatory Adjustments The fetus floats in warm amniotic fluid that is maintained at a temperature of approximately 98.6°F with very little fluctuation. Birth exposes newborns to a cooler environment in which they have to regulate their own body temperature. Newborns have a higher ratio of surface area to volume than adults. This means that their body has less volume throughout which to produce heat, and more surface area from which to lose heat. As a result, newborns produce heat more slowly and lose it more quickly. Newborns also have immature musculature that limits their ability to generate heat by shivering. Moreover, their nervous systems are underdeveloped, so they cannot quickly constrict superficial blood vessels in response to cold. They also have little subcutaneous fat for insulation. All these factors make it harder for newborns to maintain their body temperature. Newborns, however, do have a special method for generating heat: nonshivering thermogenesis, which involves the breakdown of brown adipose tissue, or brown fat, which is distributed over the back, chest, and shoulders. Brown fat differs from the more familiar white fat in two ways: • It is highly vascularized. This allows for faster delivery of oxygen, which leads to faster cellular respiration. • It is packed with a special type of mitochondria that are able to engage in cellular respiration reactions that produce less ATP and more heat than standard cellular respiration reactions. |
What do you call a predator species that affects other species' populations when its own population size changes? | complement species | paradox species | symbiotic species | keystone species | Some predator species play a special role in their community. They are called keystone species. When the population size of a keystone species changes, the populations of many other species are affected. Prairie dogs, pictured in Figure below , are an example of a keystone species. Their numbers affect most of the other species in their community. Prairie dog actions improve the quality of soil and water for plants, upon which most other species in the community depend. |
What do you call the electrons in the outer energy level of an atom that are involved in chemical bonds? | transitions electrons | force electrons | helium electrons | valence electrons | Carbon is a nonmetal in group 14 of the periodic table. Like other group 14 elements, carbon has four valence electrons. Valence electrons are the electrons in the outer energy level of an atom that are involved in chemical bonds. The valence electrons of carbon are shown in the electron dot diagram in the Figure below . |
How many valence electrons do neutral phosphorus atoms have? | four | nine | three | five | The highest-numbered shell is the third shell, which has 2 electrons in the 3s subshell and 3 electrons in the 3p subshell. That gives a total of 5 electrons, so neutral phosphorus atoms have 5 valence electrons. The 10 remaining electrons, from the first and second shells, are core electrons. |
What impact does photosynthesis have on the direction of electron flow? | cools it | repeats it | cycles it | reverses it | |
In an experiment, what is kept constant so they will not affect the results, including affecting the dependent variable? | educated controls | atmospheric controls | similar controls | experimental controls | Experimental controls are other factors that might affect the dependent variable. They are kept constant so they will not affect the results of the experiment. |
The rate of evaporation depends only on the surface area of the liquid and is essentially constant. the rate of condensation depends on the number of molecules in the vapor phase and increases steadily until it equals the rate of this? | absorption | accumulation | condensation | evaporation | The rate of evaporation depends only on the surface area of the liquid and is essentially constant. The rate of condensation depends on the number of molecules in the vapor phase and increases steadily until it equals the rate of evaporation. |
What are the two main types of diabetes? | type 3, 4 | type 0, 1 | type a, b | type 1, type 2 | There are two main types of diabetes: type 1 diabetes and type 2 diabetes. The two types of diabetes have different causes. |
What function does the longer flagellae perform in dinoflagellates? | attacks | defends | grasps | propels | 22.11.5 Pyrrophytes Pyrrophytes are unicellular, photosynthetic, and mostly aquatic. They have protective coats composed of stiff cellulose. They are more easily identifiable, due to the presence of two flagellae. The longer flagellae propels the dinoflagellate, while the second shorter, flatter flagellae functions as a rudder. Some species of pyrrophytes are zooxanthellae. Since they lack cellulose plates, they make their home in coral reefs and animals, such as sea anemones, and molluscs. In returning the favour of sheltering them, dinoflagellates provide carbohydrates to their host through photosynthesis. This is why there are nutrient-rich coral reefs in malnutritions water. A negative aspect of pyrrophytes is that under certain conditions, species of dinoflagellates reproduce rapidly to form a harmful algal bloom (HAB), known as a red tide if dinoflagellates are the cause. Such pyrrophytes can produce toxins which may injure or kill wildlife, and additionally any consumers of contaminated wildlife. |
What are the three stages of water? | liquid, underground, frozen | ice, rock, sky | vapor, earth, internal | ice, liquid, vapor | (A) Natalie Lucier; (B) Gareth Haywood; (C) Lynn Greyling. Ice, liquid, and water vapor are the three phases of water . (A) CC BY 2.0; (B) CC BY 2.0; (C) Public Domain. |
What is the first stage of cellular respiration? | breath | defacation | photosynthesis | glycolysis | Glycolysis is the first stage of cellular respiration. It takes place in the cytoplasm of the cell. The world glycolysis means "glucose splitting". That's exactly what happens in this stage. Enzymes split a molecule of glucose into two smaller molecules called pyruvate. This results in a net gain of two molecules of ATP. Other energy-storing molecules are also produced. (Their energy will be used in stage 3 to make more ATP. ) Glycolysis does not require oxygen. Anything that doesn't need oxygen is described as anaerobic . |
Roundworms are intervertebrates that belong to which phylum? | amoebozoa | annelida | Gordiacea | nematoda | Roundworms are invertebrates in Phylum Nematoda. Roundworms have a pseudocoelom and complete digestive system. They are free-living heterotrophs or parasites. |
The development of multi-cellular organisms begins from a single-celled zygote, which undergoes rapid cell division to form this? | eukaryote | gametophyte | multicell | blastula | Cleavage and Blastula Stage The development of multi-cellular organisms begins from a single-celled zygote, which undergoes rapid cell division to form the blastula. The rapid, multiple rounds of cell division are termed cleavage. Cleavage is illustrated in (Figure 43.24a). After the cleavage has produced over 100 cells, the embryo is called a blastula. The blastula is usually a spherical layer of cells (the blastoderm) surrounding a fluid-filled or yolk-filled cavity (the blastocoel). Mammals at this stage form a structure called the blastocyst, characterized by an inner cell mass that is distinct from the surrounding blastula, shown in Figure 43.24b. During cleavage, the cells divide without an increase in mass; that is, one large single-celled zygote divides into multiple smaller cells. Each cell within the blastula is called a blastomere. |
While components of a mixture can be separated by physical means, the components of a pure substance can only be broken down through what means? | thermal | mechanical | radiation | chemical | In the previous lesson, we discussed pure substances and mixtures. We indicated that the components of a mixture could be separated by physical means, but the components of a pure substance could not. Pure substances can only be broken down further through chemical means. In this lesson, we list several methods for separating mixtures. We will also be looking at chemical changes which alter the chemical identity of a substance, and how to recognize when a chemical change is taking place. |
What is it called when pollen from one plant fertilizes another plant of the same species? | cross - vegetation | cross-typing | cross-breeding | cross-pollination | Pea plants are naturally self-pollinating. In self-pollination , pollen grains from anthers on one plant are transferred to stigmas of flowers on the same plant. Mendel was interested in the offspring of two different parent plants, so he had to prevent self-pollination. He removed the anthers from the flowers of some of the plants in his experiments. Then he pollinated them by hand with pollen from other parent plants of his choice. When pollen from one plant fertilizes another plant of the same species, it is called cross-pollination . The offspring that result from such a cross are called hybrids. |
Calcium hydroxide and calcium carbonate are effective in neutralizing the effects of what on lakes? | dioxide rain | oil rain | ozone rain | acid rain | Calcium hydroxide and calcium carbonate are effective in neutralizing the effects of acid rain on lakes. Suggest other compounds that might be effective in treating lakes. Give a plausible reason to explain why Ca(OH)2 and CaCO3 are used. ♦ Approximately 95% of the chlorine produced industrially comes from the electrolysis of sodium chloride solutions (brine): NaCl(aq) + H2O(l) → Cl2(g) + H2(g) + NaOH(aq) Chlorine is a respiratory irritant whose presence is easily detected by its penetrating odor and greenishyellow color. One use for the chlorine produced is in the manufacture of hydrochloric acid. |
Most of these bacterial illnesses can be prevented with proper cooking of food and washing what? | teeth | vegetables | hair | hands | Bacteria that cause foodborne illnesses include Salmonella , a bacterium found in many foods, including raw and undercooked meat, poultry, dairy products, and seafood. Campylobacter jejuni is found in raw or undercooked chicken and unpasteurized milk. Several strains of E. coli can cause illnesses, and are found in raw or undercooked hamburger, unpasteurized fruit juices and milk, and even fresh produce. Vibrio is a bacterium that may contaminate fish or shellfish. Listeria has been found in raw and undercooked meats, unpasteurized milk, soft cheeses, and ready-to-eat deli meats and hot dogs. Most of these bacterial illnesses can be prevented with proper cooking of food and washing of hands. |
If something is in the state of matter where it has both a definite shape and volume, then what state of matter is it in? | liquid | gas | plasma | solid | |
What is the region known as the myelencephalon in the embryonic brain? | Diencephalon | Telencephalon | Mesencephalon | medulla | Medulla The medulla is the region known as the myelencephalon in the embryonic brain. The initial portion of the name, “myel,” refers to the significant white matter found in this region—especially on its exterior, which is continuous with the white. |
What involves the reaction of a hydrocarbon with oxygen gas to produce water and carbon dioxide? | material reactions | hydrogen reactions | chemical reactions | combustion reactions | Combustion reactions involve the reaction of a hydrocarbon with oxygen gas to produce water and carbon dioxide. |
What law states that matter cannot be created or destroyed? | construct of energy | Murphy's Law | law of inertia | conservation of energy | The law of conservation of energy states that matter cannot be created or destroyed. Whether a chemical reaction absorbs or releases energy, there is no overall change in the amount of energy during the reaction. |
The air bubbles resulting from cavitation expand and block water channels of the what? | ectoderm | heart | respiration | xylem | |
Which gender typically experiences growth spurts first? | transgender | no difference | male | female | Like boys, girls also go through an adolescent growth spurt . However, girls typically start their growth spurt a year or two earlier than boys (and therefore a couple of centimeters shorter, on average). Girls also have a shorter growth spurt. For example, they typically reach their adult height by about age 15. In addition, girls generally do not grow as fast as boys do during the growth spurt, even at their peak rate of growth. As a result, females are about 10 centimeters (about 4 inches) shorter, on average, than males by the time they reach their final height. |
What are the only organisms that can decompose wood? | fossil | bacteria | protists | fungi | Saprotrophs are the final step in decomposition. They feed on any remaining organic matter that is left after other decomposers do their work. Saprotrophs include fungi and single-celled protozoa. Fungi are the only organisms that can decompose wood. |
What part of the plant do nutrients enter? | the stem | the seeds | the flower | the roots | |
What is a solid particle that is indestructible? | neutron | quark | nucleus | atom | Atoms are solid particles that are indestructible. |
Activated macrophages and neutrophils discharge what that signals molecules that enhance an immune response? | nucelotides | alkaloids | pathogens | cytokines | |
The extracellular fluid is in contact with the axon membrane only at what location? | Sensory Receptors | dendrites | synapses | the nodes | |
Muscarinic receptors can cause both depolarization or hyperpolarization depending on the what? | phenotype | strain | gravity | subtype | Nicotinic receptor causes depolarization. Muscarinic receptors can cause both depolarization or hyperpolarization depending on the subtype. |
What does rising air do when it reaches the top of the troposphere? | warms | dries | heats | cools | The rising air cools as it reaches the top of the troposphere. The air gets denser, so it sinks to the surface. The sinking, heavy air creates an area of high air pressure near the ground. |
The what is the number of wave cycles that pass a specified point in space in a specified amount of time? | density | vibrancy | intensity | frequency | Waves need not be restricted to travel through matter. As Maxwell showed, electromagnetic waves consist of an electric field oscillating in step with a perpendicular magnetic field, both of which are perpendicular to the direction of travel. These waves can travel through a vacuum at a constant speed of 2.998 × 108 m/s, the speed of light (denoted by c). All waves, including forms of electromagnetic radiation, are characterized by, a wavelength (denoted by λ, the lowercase Greek letter lambda), a frequency (denoted by ν, the lowercase Greek letter nu), and an amplitude. As can be seen in Figure 6.2, the wavelength is the distance between two consecutive peaks or troughs in a wave (measured in meters in the SI system). Electromagnetic waves have wavelengths that fall within an enormous range-wavelengths of kilometers (103 m) to picometers (10−12 m) have been observed. The frequency is the number of wave cycles that pass a specified point in space in a specified amount of time (in the SI system, this is measured in seconds). A cycle corresponds to one complete wavelength. The unit for frequency, expressed as cycles per second [s−1], is the hertz (Hz). Common multiples of this unit are megahertz, (1 MHz = 1 × 106 Hz) and gigahertz (1 GHz = 1 × 109 Hz). The amplitude corresponds to the magnitude of the wave's displacement and so, in Figure 6.2, this corresponds to one-half the height between the peaks and troughs. The amplitude is related to the intensity of the wave, which for light is the brightness, and for sound is the loudness. |
Intermediate filaments tend to give the structural stability to what? | muscles | nerves | proteins | cells | 8.7.1 Intermediate Filaments These are rope like filaments, 8-10nm in diameter and tend to give the structural stability to cells. Examples inculude Vimentin, neurofilaments and keratin. It is keratin which priniciply makes up hair, nails and horns. |
What is the process in which a layer of a second metal is deposited on the metal electrode that acts as the cathode during electrolysis? | distillation | casting | cold fusion | electroplating | Electroplating In a process called electroplating, a layer of a second metal is deposited on the metal electrode that acts as the cathode during electrolysis. Electroplating is used to enhance the appearance of metal objects and protect them from corrosion. Examples of electroplating include the chromium layer found on many bathroom fixtures or (in earlier days) on the bumpers and hubcaps of cars, as well as the thin layer of precious metal that coats silver-plated dinnerware or jewelry. In all cases, the basic concept is the same. A schematic view of an apparatus for electroplating silverware and a photograph of a commercial electroplating cell are shown in Figure 19.24 "Electroplating". |
What is the term for diseases in which blood does not clot normally? | lymphoma | arthritis | diabetes | hemophilia | Hemophilia is a group of diseases in which blood does not clot normally. Factors in blood are involved in clotting. When you bleed, your body begins a coagulation cascade of reactions, involving special proteins known as coagulation factors, to stop that bleeding. When one or more of these clotting factors are missing, there is a higher chance of having dificulties stoping the bleeding. Hemophiliacs lacking the normal Factor VIII are said to have Hemophilia A (or Factor VIII deficiency), the most common form. Hemophilia is a genetic disease, passed down through family. It is linked to the X-chromosome, so it mostly affects males. F8 is the gene for the Factor VIII protein. Mutations in the F8 gene lead to the production of an abnormal version of coagulation factor VIII, or reduce the amount of the protein. The altered or missing protein cannot participate effectively in the blood clotting process. |
Cardiomyocytes are striated muscle cells found where? | in the intestines | in the diaphram | in lung tissue | in cardiac tissue | Figure 40.13 Cardiomyocytes are striated muscle cells found in cardiac tissue. (credit: modification of work by Dr. Girod, Anton Becker; scale-bar data from Matt Russell). |
Which protein, that stores oxygen in muscle cells, has been purified from a number of organisms? | iodine | melanin | potassium | myoglobin | Myoglobin, a protein that stores oxygen in muscle cells, has been purified from a number of organisms. The protein from a sperm whale is composed of 153 amino acid units. What is the minimum number of nucleotides that must be present in the mRNA that codes for this protein?. |
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