The Final Exam in Biol 178 is comprehensive. This study guide has sample questions related only to Evolution and Ecology. Use previous study guides/exams for other sections of the comprehensive final exam. 1. Natural selection as a mechanism of evolution that acts on variants within populations and ultimately leads to the evolution of different species was proposed by A. Mendel. B. Lyell. C. Malthus. D. Darwin. E. Founder. 2. Features that increase the likelihood of survival and reproduction by an organism in a particular environment are called A. genes. B. fitness. C. mutations. D. adaptations. E. selection. 3. The gene pool includes A. all of the fitness within a population. B. all of the individuals within a population. C. all of the mutations within a population. D. all of the adaptations within a population. E. all of the alleles of genes within a population. 4. The founder principle explains how rare alleles may become more common in new A. populations. B. clines. C. bottleneck areas. D. migratory areas. E. genomes. 5. A restriction in genetic variability caused by a drastic reduction in population size is called a A. founder effect. B. Hardy-Weinberg effect. C. bottleneck effect. D. polymorphic effect. E. adaptive effect. 6. The genetic contribution of an individual to succeeding generations, compared with that of other individuals in the population, is known as A. variation. B. microevolution. C. macroevolution. D. fitness. E. adaptive makeup.

7. Darwin proposed that natural selection occurs in an environment by A. favoring heritable features that make the organism better suited to survive and reproduce. B. producing a constant number of offspring while in that environment. C. surviving for a fixed amount of time. D. resisting the environment and keeping the environment from changing. E. favoring those individuals with the most favorable acquired characteristics. 8. The Hardy-Weinberg equations only hold true, that is, a population is only in equilibrium A. when immigration in and out of the area are held constant. B. when changes only take place over long periods of time. C. when it includes episodes of extinction. D. when the population is designed to survive in new habitats. E. when all of the Hardy-Weinberg assumptions are met. 9. In the Hardy-Weinberg equations, the frequencies of 2 alleles in a population (where there are only 2 alleles to consider) can be designated as A. (p + q)2. B. p and q. C. p2 and q2. D. 2pq. E. 1 - p and 1 - q. 10. The frequency of a particular allele within a population can be changed, over time, by A. genetic outflow. B. large population size. C. selection. D. inheritance of acquired characteristics. E. random mating. 11. The genetic preservation of the features that increase the likelihood of survival and reproduction of some individuals within a population is called the process of A. natural selection. B. creation of new species. C. genetic drift. D. outcrossing. E. increasing evolutionary resistance. 12. For a gene with two alternative alleles, a (frequency p) and a (frequency q), the term in the algebraic form of the Hardy-Weinberg equilibrium for the heterozygote genotype frequency is A. p2. B. q2. C. 2pq. D. (p+q)2. E. 2Aa.

13. Which one of the following is not an agent of natural evolutionary change? A. mutation B. migration C. genetic drift D. non-random mating E. artificial selection 14. The phenomenon in which rare alleles become more common in new populations is called A. founder effect. B. gene flow. C. genetic drift. D. assortative mating. E. mutation. 15. In small populations, frequencies of certain alleles may change by chance alone. Such random change in the frequency of alleles is called A. mutation. B. migration. C. genetic drift. D. nonrandom mating. E. selection. 16. The type of non-random mating that causes the frequencies of particular genotypes to differ greatly from those predicted by the Hardy-Weinberg equilibrium is called A. mutation. B. migration. C. genetic drift. D. assortative mating. E. selection. 17. Sometimes a restriction in genetic variability is imposed on populations by natural catastrophes such as flooding, earthquake, etc. The surviving individuals reflect only a small, random genetic sample of the population affected. This process is termed A. mutation. B. migration. C. genetic drift. D. assortative mating. E. bottleneck effect. 18. Which one of the following is not an agent of evolutionary change? A. mutation B. gene flow C. random mating D. genetic drift E. selection

19. In order for natural selection to occur within a population, certain conditions must be met. One such condition is A. phenotypic differences resulting from environmental conditions. B. frequent mutations that are inherited. C. low rates of immigration. D. phenotypic variations that are genetic. E. heterozygosity must be very low. 20. When selection acts to eliminate one extreme from an array of phenotypes it is called A. natural selection. B. stabilizing selection. C. disruptive selection. D. directional selection. E. artificial selection. 21. The total of all the alleles of all the genes in a population can be thought of as A. an allele mixture. B. a gene pool. C. a genetic melting pot. D. a genome. E. variant genes. 22. Cheetahs have been through a genetic bottleneck; evidence for this is that A. little natural selection occurs in this species. B. the body is long, thin, and graceful. C. there is very little genetic variability. D. these cats are members of an endangered species. E. they originally came from small areas of Africa. 23. The Hardy-Weinberg equilibrium conditions for populations of organisms result in A. polymorphic alleles. B. assortive mating. C. natural selection. D. maintenance of recessive alleles in the gene pool. E. no evolutionary changes. After a coastal storm 3 deermice (Peromyscus), huddled on a tree trunk, are carried many miles out to sea and wash ashore on a small island that has no mice, but does have habitat to support them. Two of the mice are female, and both mate with the only male. 24. At least some of the requirements for a Hardy-Weinberg equilibrium would be in effect on the island. For instance there is probably A. a high rate of immigration. B. a very large population size. C. little gene flow. D. no mutation. E. random mating.

25. In disruptive selection, over time A. a population goes extinct. B. the most extreme outliers of a population are eliminated (e.g., the largest beaks and smallest beaks are eliminated). C. the population is strongly selected for in one direction (e.g., larger beak size). D. the population is strongly selected for in two directions (e.g., larger beak size and smaller beak size). E. a population increases its variation (e.g., a wide selection of all beak sizes). 26. In directional selection, over time A. a population goes extinct. B. the most extreme outliers of a population are eliminated (e.g., the largest beaks and smallest beaks are eliminated). C. the population is strongly selected for in one direction (e.g., larger beak size). D. the population is strongly selected for in two directions (e.g., larger beak size and smaller beak size). E. a population increases its variation (e.g., a wide selection of all beak sizes). 27. If the frequency of an autosomal recessive trait in humans is 1 out of 4000 births, what would be the expected frequency of heterozygote carriers for the trait if we assume that the gene is in Hardy-Weinberg equilibrium? A. 0.00025 B. 0.0158 C. 0.031 D. 0.969 E. 0.984 28. Which of the following would be expected to produce the largest evolutionary change in a given period of time in a population of birds? A. mutation B. natural selection C. migration D. random mating E. Hardy-Weinberg equilibrium 29. The recessive phenotype of a trait occurs in 20% of a population. There are no selection pressures affecting this trait. What would be the expected frequency of the dominant allele after six generations of continued non-selection? A. 0.2 B. 0.306 C. 0.447 D. 0.494 E. 0.553 30. The recessive phenotype of a trait occurs in 20% of a population. There are no selection pressures affecting this trait. What would be the expected frequency of the heterozygote genotype after six generations of continued non-selection? A. 0.2 B. 0.306 C. 0.447 D. 0.494 E. 0.553 31. The genotype frequencies in a population with no evolution occurring are AA = 0.25, Aa = 0.5, aa = 0.25. By removing all AA individuals before they reproduce and assuming the population will remain under Hardy-Weinberg conditions, what will be the frequency of aa individuals in the next generation? A. 0.25 B. 0.33 C. 0.5 D. 0.67 E. 0.75

32. In a large population of randomly reproducing rabbits, a recessive allele r comprises 80% of the alleles for a gene, while a dominant allele R comprises the remaining 20%. What percentage of the rabbits would you expect to have the recessive phenotype? A. 4% B. 32% C. 64% D. 80% E. none 33. Coloration in the peppered moth (Biston betularia) is determined by a single gene with two alleles showing complete dominance. Dark moths are homozygous dominant or heterozygous for the gene, light moths are homozygous recessive. In a sample of 100 moths, you determine that 64 of the moths are dark. According to the Hardy-Weinberg rule, the expected frequency of the dominant allele is ____. A. 0.4 B. 0.36 C. 0.6 D. 0.64 E. cannot be determined 34. The California populations of the Northern elephant seal are descendants from a very small population of seals that was over-hunted in the 1890s. Heterozygosity in this population would be expected to be ________ due to ________________. A. slight; a bottleneck effect B. slight; the founder effect C. great; disruptive selection D. great; a bottleneck effect E. great; assortive mating 35. Natural selection varies the shape of the beaks among Darwin's finches in response A. to the available food supply. B. to the available nest building material supplies. C. to the availability of potential mating partners. D. to presence of ectoparasites on their feathers. E. to the need to improve their feather preening abilities. 36. A technique used in dating a rock can be used to accurately predict the age of the fossils occurring in the rocks. This technique involves A. fossil dating. B. successive rock layering. C. radioactive isotope decay. D. structural geology. E. developmental geology. 37. The evolution of similar forms in different lineages when exposed to the same selective pressures is A. called divergence. B. called convergence. C. referred to as successive homologies. D. referred to as descent. E. also known as natural selection.

38. Industrial melanism is a term describing A. the color change induced by living in industrialized areas. B. the darker moths having higher mutation rates because of industrialization. C. the evolutionary process in which initially light-colored organisms become dark as a result of natural selection. D. the darker moths having higher reproductive success because of their pigmentation. E. the widespread implementation of pollution controls. 39. The shape of the beaks of Darwin's finches, industrial melanism, and sickle-cell disease are often cited as examples of the process of _______________ leading to evolutionary change. A. artificial selection B. coevolution C. intelligent design D. founder effect E. natural selection 40. Today, the fossil record A. can be dated only with one layer in relation to older layers below and younger layers above, no actual dates can be estimated. B. can be dated reasonably well only with uranium-238. C. can be dated reasonably well using a variety of radioactive isotopes with known half-lives. D. can be dated precisely, to within a single year, using radioactive isotopes. E. can be dated precisely, to within a single year, using DNA hybridization. 41. Darwin concluded that evolution was at work by studying the shapes of A. seeds. B. malarial parasites. C. peppered moths. D. hemoglobins. E. beaks of finches. 42. Evidence for evolution includes all of the following except A. the fossil record. B. homologous structures. C. the molecular record. D. intelligent design. E. vestigial structures. 43. Evidence for evolution can be obtained by examining presently existing species through studies on each of the following except one. Select the exception. A. early development B. vestigial structures C. patterns of distribution D. convergence E. analogous structures

44. Progressive changes in fossils of different ages provides one of the strongest lines of evidence for A. extinction. B. evolution. C. coevolution. D. adaptation. E. mutation. 45. The molecular record suggests that a series of evolutionary changes is tied to a progressive accumulation of A. extinctions. B. alterations of DNA sequences. C. modifications of the environment. D. somatic mutations. E. structural modifications. 46. Structures that are derived from the same body part in a common ancestor but may have different appearances and functions are called A. analogous structures. B. homologous structures. C. vestigial structures. D. embryonic structures. E. homozygous structures. 47. Which of the reasons does not explain why "scientific creationism" cannot be considered a science? A. It is not supported by any empirical observations. B. It does not obtain its principles from observation, as does science. C. Its assumptions lead to no hypotheses that could be tested and possibly disproved. D. The idea of creation by a supernatural agency lies outside the realm of science. E. Only non-scientists believe it. 48. The wings of birds and butterflies are examples of structures that resemble each other and have similar function, but are the result of parallel evolution in separate lineages. These structures are called A. analogous structures. B. homologous structures. C. vestigial structures. D. embryonic structures. E. homozygous structures. 49. Many organisms possess structures that have no apparent function, but they resemble structures of presumed ancestors. This is the study of A. the fossil record. B. the molecular record. C. homology. D. development. E. vestigial structures.

50. The observation that different geographical areas sometimes exhibit plant and animal communities of similar appearance, even though the individual plants and animals are not closely related, is called A. the fossil record. B. homology. C. convergent evolution. D. divergent evolution. E. adaptation. 51. Which of the following is an example of convergent evolution? A. Australian marsupials and placental mammals of other continents B. analogous organs of horses, antelopes, and deer C. homologous organs of apes and humans D. skull bones of vertebrates E. all of the species in a genus of placental mammals 52. The evolution of different forms in the same lineage when exposed to different selective pressures is called A. convergence. B. homology. C. phylogeny. D. analogy. E. divergence. Marsupials are a very ancestral form of mammal, evolving before placental mammals over 70 million years ago. Today Australian marsupials can be compared to placental mammals on other continents. 53. It could be said that today's Australian marsupials and today's placental mammals have A. undergone divergent evolution. B. undergone selective advantage. C. undergone heterozygote advantage. D. undergone convergent evolution. E. developed homologous structures. 54. Industrial melanism involving the peppered moths (Biston sp.) is cited as an example of natural selection that has been observed in the last one hundred years. Recall that the peppered moth exhibits two distinct morphological types with dark and light colored wings. Which of the following statements about changes in these two types of moths as a result of industrial melanism is true? A. The dark forms are selected against in nonpolluted forests. B. The dark forms are distasteful to birds and are thus safe in polluted forests. C. The light forms are selected against in nonpolluted forests. D. Birds prey on the dark and light forms equally and neither morph has an advantage. E. Dark forms emigrate from nonpolluted forests to polluted forests.

55. A friend is trying to understand the concept of convergent evolution. Which one of the following statements best describes this concept? A. Convergent evolution occurs when two species living in the same area become reproductively isolated. B. Convergent evolution occurs when two species living in different areas become reestablished and are able to reproduce. C. Convergent evolution occurs when two species living in the same area are competing for the same resource thus causing one to evolve away from the other. D. Convergent evolution occurs when two species living in different areas evolve similarities through natural selection acting on those characteristics. 56. A biologist seeing a sign describing evolution as "just a theory" would think that A. evolution is a theory that is supported with a tremendous amount of evidence. B. evolution is just a collection of facts without a central theme and this is not a theory. C. evolution is what Darwin proposed to account for all the changes he observed in the finches so it is a hypothesis, not a theory. D. evolution occurred in the past, but it is not occurring in the present, so it cannot be a theory. 57. You see a sign on a door that reads "Homologous Structures Inside." You go in and find A. structures of animals that appear to have evolved from different parts of their bodies. B. structures of animals that have difference appearances and functions but seem to have evolved from the same body part in a common ancestor. C. structures of animals that have the same appearances and functions but obviously no common ancestor. D. structures of animals that have different appearances and functions but different ancestors. 58. Radioactive isotopes are used in dating materials from the distant past. Which of the following statements about radioactive dating techniques is true? A. It gives the general ages of rock strata. (± 1 million years). B. It gives exact ages of rock strata. (± 1 year). C. It uses a technique in which the degree of radioactive decay is measured, the younger the rock the more radioactive decay. D. It uses a technique in which the degree of radioactive decay is measured, the older the rock the more radioactive decay. E. It does not work well with fossil remains that have not absorbed radiation. 59. In comparing artificial and natural selection, which of the following statements is true? A. Artificial selection is slower than natural selection. B. Artificial selection is reversible; natural selection is not. C. Artificial selection can produce maladaptive structures, natural selection cannot. D. Artificial selection cannot produce changes as large as changes produced by natural selection. E. In artificial selection, the magnitude of the selection pressure can be varied; in natural selection, it cannot. 60. A rock contains 18 mg of the radioactive isotope carbon-14. The half-life of carbon-14 is 5,600 years. How many half-lives and years will it take before the carbon-14 decays to less than 4 mg? A. 1 half-lives; 5,600 years B. 2 half-lives; 11,200 years C. 3 half-lives; 16,800 years D. 4 half-lives; 22,400 years E. 9 half-lives; 50,400 years

61. The half-life of carbon-14 is 5,600 years. A fossil that has one-eighth the normal proportion of carbon-14 to carbon-12 is probably A. 2,800 years old. B. 5,600 years old. C. 11,200 years old. D. 16,800 years old. E. 22,400 years old. 62. The most precise method of obtaining estimates of the absolute ages of geological deposits is A. measure rates of sedimentary rock formation. B. measure the ratios of various radioactive isotopes in the deposits. C. apply the principle of superposition (younger deposits above older deposits). D. make salinity measurements in ocean sediment deposits. E. study the sequence of fossil types in the deposits. 63. The side toes of a horse, the pelvis of the whale, and the human appendix are all examples of A. analogous structures. B. homologous structures. C. vestigial structures. D. homeotic mutations. E. acquired structures. 64. The convergence in form seen in sharks, tuna, and dolphins best relates to A. a recent shared common ancestor. B. dissimilar selection pressures. C. the physical properties of water. D. the need to escape fast-moving predators. E. intelligent design. 65. Two groups of organisms that differ from one another in one or more characteristics and do not hybridize extensively if they occur together in nature are considered to be different A. races. B. species. C. kingdoms. D. hybrids. E. cohabitants. 66. Once species have formed, they keep their identity by A. developmental differences. B. genetic blocks. C. isolating mechanisms. D. somatic mutations. E. structural modifications. 67. A classical example of adaptive radiation is seen in A. peppered moths. B. mules. C. Darwin's finches. D. Hawaiian finches. E. mainland birds.

68. Species formation among alpine buttercups in New Zealand was promoted by A. mechanical isolation. B. gametic isolation. C. periodic isolation by glaciation. D. temporal isolation. E. geographical isolation. 69. All of the following describe members of a species except A. they have several isolated gene pools. B. they differ from other species in one or more characteristics. C. they cannot hybridize freely with other species members. D. they can interbreed freely with all other members. E. for potential gene flow with all other members. 70. A group of individuals of a single species living together is a A. deme. B. phenotype. C. genome. D. biotic community. E. population. 71. A community and the nonliving factors with which it interacts is called a(n) A. population. B. race. C. cline. D. environment. E. ecosystem. 72. The number of individuals of a species that can be supported indefinitely in a particular place is called its A. niche. B. biotic potential. C. carrying capacity. D. maximum size. E. habitat usage. 73. Population pyramids are primarily used to show A. death rates. B. birth rates. C. competition. D. sex and age composition of a population. E. the carrying capacity. 74. All of the following apply to the demography of human populations today except A. we use almost half of the Earth's land. B. we use over half of all renewable fresh water sources. C. we are unevenly distributed and the difference is increasing. D. we are using distributed resources unevenly—less than 20% of us use over 80% of the energy. E. our ecological footprint is decreasing.

75. You construct a life table for a plant species and find that in all cases about the same proportion of the cohort survive to the beginning of the next time interval. Such a plant would have A. a Type I survivorship curve. B. a Type II survivorship curve. C. a Type III survivorship curve. D. a semelparous life history adaptation. E. populations regulated by density-independent events. 76. The way in which an organism utilizes its environment may be called A. resource partitioning. B. its habitat. C. competitive exclusion. D. intraspecific competition. E. its niche. 77. Communities evolve to have greater biomass and species richness in a process called A. sympatric interactions. B. adaptive modifications. C. succession. D. symbiotic relationships. E. competitive exclusion. 78. Insects that feed on milkweed plants are generally brightly colored. Such coloration is called A. Batesian mimicry. B. apoptosis. C. cryptic coloration. D. warning coloration. E. Müllerian mimicry. 79. Some insects that lack any specific chemical defenses blend with their environment to avoid predators. This type of defense strategy is called A. Batesian mimicry. B. apoptosis. C. cryptic coloration. D. warning coloration. E. Müllerian mimicry. 80. Which of the following gases in the atmosphere appears to be changing the global climates? A. ozone B. water vapor C. carbon dioxide D. hydrogen E. oxygen 81. Which of the following feed directly on the green plants? A. primary producers B. primary consumers C. secondary consumers D. secondary producers E. decomposers

82. Organisms that break down organic matter are called A. detritivores. B. omnivores. C. herbivores. D. carnivores. 83. All of the following are true about ecosystems except A. they contain both living and nonliving components. B. there is a transfer of energy through the system and it is lost. C. there is a cycling of nutrients through the system again and again. D. the ultimate source of energy is the sun for nearly all known ecosystems. E. they represent the lowest level of biological organization that is known. 84. All of the following undergo biogeochemical cycles except A. carbon. B. energy. C. nitrogen. D. sulfur. E. water. 85. In global terms, the production of CO2 by respiration and its fixation by photosynthesis are balanced, but the balance has been shifted towards accumulation of CO2 by the increase in use of A. meat products. B. vegetable products. C. fossil fuels. D. all types of foods. E. nuclear energy. 86. Energy enters the ecosystem mainly by the process of A. biosynthesis. B. nutrition. C. biogeochemical weathering. D. photosynthesis. E. metabolism. 87. The primary consumers are A. autotrophs. B. carnivores. C. decomposers. D. detritivores. E. herbivores. 88. The organisms that live on the refuse of an ecosystem are called A. autotrophs. B. carnivores. C. denitrifiers. D. detritivores. E. herbivores.

89. A good average value for the amount of organic matter that reaches the next trophic level is about A. 20%. B. 10%. C. 5%. D. 2%. E. 1%. 90. In an ecosystem, which statement reflects the relationship with energy and nutrients? A. Energy cycles and nutrients also cycle in a balanced ecosystem. B. Energy flows and nutrients cycle in an ecosystem. C. Energy cycles and nutrients flow in an ecosystem. D. Energy flows and nutrients flow through an ecosystem. E. In an unbalanced ecosystem, nutrients are stored in energy cycles. 91. Which of the following choices best describes the relationship that exists between photosynthesis and cellular respiration? A. Photosynthesis captures and stores carbon from the atmosphere. Cellular respiration releases carbon back into the atmosphere. B. Photosynthesis captures and stores carbon from the atmosphere as does cellular respiration. C. Photosynthesis releases carbon into the atmosphere. Cellular respiration captures and stores carbon from the atmosphere. D. Photosynthesis releases carbon into the atmosphere as does cellular respiration. 92. Which one of the links in the food chain shown below does the cricket represent? grass—cricket—garden spider—blue jay—red-tailed hawk A. producer B. primary producer C. primary consumer D. secondary consumer E. tertiary consumer 93. Which one of the links in the food chain shown below is the producer? grass—cricket—garden spider—blue jay—red-tailed hawk A. grass B. cricket C. garden spider D. blue jay E. red-tailed hawk 94. Which one of the links in the food chain shown below does the garden spider represent? grass—cricket—garden spider—blue jay—red-tailed hawk A. producer B. primary producer C. primary consumer D. secondary consumer E. tertiary consumer

95. In a food chain with four trophic levels, what would be the energy in the top trophic level if the energy contained in the primary producer level is 40,000 kcal/m2/yr? Assume a trophic level transfer efficiency of 10%. A. 4,000 kcal/m2/yr B. 400 kcal/m2/yr C. 40 kcal/m2/yr D. 4 kcal/m2/yr E. 0.4 kcal/m2/yr 96. In a food chain consisting of four trophic levels, if the energy present in the top level is 48 kcal/m2/yr, how much energy do you expect in primary consumers? (Use an energy transfer rate of 10%.) A. 4.8 kcal/m2/yr B. 48 kcal/m2/yr C. 480 kcal/m2/yr D. 4,800 kcal/m2/yr E. 48,000 kcal/m2/yr 97. The richest land biome in terms of the number of different species is the A. tundra. B. temperature deciduous forest. C. savannas. D. grasslands. E. tropical rain forest. 98. Which of the following is not one of the characteristics of a biome? A. They include terrestrial communities the world over. B. They contain the same species throughout their range. C. They occur over wide areas. D. They are recognized by their overall appearance. E. They have characteristic climates. 99. One of the most serious and rapidly accelerating of all global environmental problems is the loss of A. carbon dioxide in the tropical forests. B. ground water in the tropical forests. C. cloud cover in the tropical forests. D. nutrients in the tropical forests. E. biodiversity in the tropical forests. 100. Most of the ultraviolet radiation reaching the upper atmosphere is absorbed by A. CFCs. B. ozone. C. nitrogen. D. carbon dioxide. E. water vapor. 101. The biome which contains at least half of Earth's plants and animals is the A. desert. B. grassland. C. savanna. D. taiga forest. E. tropical rain forest.

102. A layer of ozone in the upper atmosphere shields Earth from most A. acid rain. B. bacterial diseases. C. greenhouse effects. D. solar ultraviolet radiation. E. water pollution. 103. The major cause of thinning of the ozone layer was attributed to A. greenhouse gases. B. nitric and sulfuric acids. C. chloroflorocarbons. D. phosphorus. E. water vapor. 105. Chlorinated hydrocarbons cause A. "Biological magnification." D. greenhouse effect.

B. air pollution. E. acid precipitation.

C. ozone hole.

106. A friend asks you about what has caused global warming. You explain A. as carbon dioxide and other gases have increased in the atmosphere, the global temperature has increased due to trapped solar radiation. B. as carbon dioxide and other gases have increased in the atmosphere, the global temperature has increased due to ozone depletion. C. as carbon dioxide and other gases have increased in the atmosphere, the global temperature has increased due to acid precipitation changing the pH of the atmosphere. D. that there really is no evidence for global warming and these are mere scare tactics being used by environmentalists to reduce oil consumption. 107. Which of the following gases is most associated with global warming? A. oxygen B. ozone C. nitrous oxides D. carbon dioxide E. chlorofluorocarbons 108. Biomagnification is a significant problem in aquatic communities. The amounts of chemicals magnify (increase or accumulate) at each new link in a food chain. Use the following information to calculate the level of chemical X in the large-mouth bass. One small plant can accumulate 1 unit of chemical X. A microscopic animal eats 15 small plants. A minnow consumes 10 microscopic animals, a large-mouth bass consumes 20 minnows. A. 15 units of chemical X B. 30 units of chemical X C. 150 units of chemical X D. 300 units of chemical X E. 3,000 units of chemical X 109. Temperate grasslands and temperate deciduous forests are two different biomes that are located in the same latitudes. Which one of the following abiotic conditions is most likely to account for the differences in their community composition? A. temperature B. precipitation C. sunlight D. soil nutrients E. a rain shadow 110. Biological magnification of persistent toxins should be greatest in A. herbivores. B. primary carnivores. C. secondary carnivores.

D. detritivores.