CH 18 Practice Questions

Each of the phenomena listed below might (or might not) result in a violation of the assumptions required to maintain Hardy-Weinberg equilibrium. For each one, provide the letter for the Hardy-Weinberg assumption that it violates. Phenomenon Hardy-Weinberg Assumptions A. the population is large B. there is no mutation C. there is no migration D. mating is at random E. all genotypes survive and reproduce equally well (no natural selection)

10._C_gene flow 11._A_population bottleneck 12._E_heterozygote advantage 13._D_ inbreeding

11) Races of humans are unlikely to evolve extensive differences in the future for which of the following reasons? I. The environment is unlikely to change. II. Human evolution is complete. III. The human races are incompletely isolated. 11) ____ A) III only B) I, II, and III C) II and III only D) I only E) I and II only

A

18. He had a good idea ("organisms evolve by adapting to their environment") but a faulty mechanism ("inheritance of acquired characteristics"). A. Lamarck B Aristotle C. Buffon D. Linnaeus E. Lyell

A

20. Darwin proposed that new species evolve from ancestral forms by ____. A. populations' gradual accumulation of heritable adaptations to varying environments B. populations independently converging on similar well-adapted phenotypes in different environments C. the accumulation of mutations in isolated populations D. the exponential growth of populations in new environments E. the use or disuse of morphological structures in separate populations

A

22. A midnight raid of gator poachers canoes down the Wakulla River and they kill off 84 of the 100 gators in the problem above, taking the population out of Hardy-Weinberg equilibrium, and leaving only 12 gators that are heterozygous (Bb) for bad breath and 4 that have sweet-smelling (bb) breath (to another gator maybe!). What is the frequency of the recessive allele in the new population? A. 0.625 B. 0.16 C. 0.438 D. 0.375 E. it cannot be determined

A

24. A case of disruptive selection: a population of fruit-picking monkeys consists of monkeys with either long digits (making it easier to grasp large fruits) or short digits (better able to manipulate small fruits). A. True B. False

A

25. Which of the following represents an idea Darwin took from the writings of Thomas Malthus? A. Populations tend to increase at a faster rate than their food supply. B. The environment is responsible for natural selection. C. All species are fixed in the form in which they are created. D. Earth is more than 10,000 years old. E. Earth changed over the years through a series of catastrophic upheavals.

A

27. If an allele is recessive and lethal in homozygotes for this allele, then which of the following is true? A. The allele will likely remain in the population at low frequency because it cannot be selected against when in a heterozygote. B. The relative fitness (w) of the homozygous recessive genotype is 1. C. The allele will be present in the population at frequency of 0.001. D. The allele will be removed from the population in approximately 1000 years. E. none of the above

A

27. Which statement best describes how the evolution of pesticide resistance occurs in a population of insects? A. A number of genetically resistant pesticide survivors reproduce. The next generation of insects contains more genes from the survivors than it does from susceptible individuals. B. Individual members of the population slowly adapt to the presence of the chemical by striving to meet the new challenge. C. Insects observe the behavior of other insects that survive pesticide application, and adjust their own behaviors to copy those of the survivors. D. All insects exposed to the insecticide begin to use a formerly silent gene to make a new enzyme that breaks down the insecticide molecules. E. B and D only

A

33) When imbalances occur in the sex ratio of sexual species that have two sexes (i.e., other than a 50:50 ratio), the members of the minority sex often receive a greater proportion of care and resources from parents than do the offspring of the majority sex. This is most clearly an example of _______. A) frequency-dependent selection. B) sexual selection. C) disruptive selection. D) balancing selection. E) stabilizing selection.

A

33. Which of the following is a likely result of genetic drift? A. gene fixation B. introduction of new alleles C. natural selection D. gene flow E. migration

A

36) If the HMS Beagle had completely bypassed the Galapagos Islands, Darwin would have had a much poorer understanding of _______. A) the ability of populations to undergo modification as they adapt to a particular environment. B) the tendency of organisms to produce a larger number of offspring than the environment can support. C) the age of Earth. D) the limited resources available to support population growth in most natural environments. E) how fossils of marine organisms could be found high in the Andes.

A

39) Members of two different species possess a similar-looking structure that they use in a similar fashion to perform the same function. Which information would shed the most light on whether these structures are homologous or whether they are, instead, the result of convergent evolution? A) The two species share many proteins in common, and the nucleotide sequences that code for these proteins are almost identical. B) Both species are well adapted to their particular environments. C) The sizes of the structures in adult members of both species are similar in size. D) Both species reproduce sexually. E) The two species live at great distance from each other.

A

40) The theory of evolution is most accurately described as _______. A) a broad explanation, supported by much evidence, for how populations change over time. B) an educated guess about how species originate. C) an opinion that some scientists hold about how living things change over time. D) an idea about how acquired characteristics are passed on to subsequent generations. E) one possible explanation, among several scientific alternatives, about how species have come into existence.

A

5) Which statement represents the best explanation for the observation that the nuclear DNA of wolves and domestic dogs has a very high degree of homology? A) Dogs and wolves shared a common ancestor very recently. B) Dogs and wolves have very similar morphologies. C) Dogs and wolves are both members of the family Canidae. D) Convergent evolution has occurred. E) Dogs and wolves belong to the same order.

A

7. Kettlewell's experiment showing that light and dark-colored peppered moths had differential survival in sooty, urban environments compared to cleaner, rural environments was an important early experimental study that demonstrated _____. A. natural selection B. genetic drift C. melanism is a heritable trait D. early evidence of global warming E. frequency-dependent selection

A

A large population of laboratory animals has been allowed to breed randomly for a number of generations. After several generations, 36% of the animals display a recessive trait (aa), the same percentage as at the beginning of the breeding program. The rest of the animals show the dominant phenotype, with heterozygotes indistinguishable from the homozygous dominants. 18) What is the most reasonable conclusion that can be drawn from the fact that the frequency of the recessive trait (aa) has not changed over time? A) The two phenotypes are about equally adaptive under laboratory conditions. B) The genotype AA is lethal. C) There has been sexual selection favoring allele a. D) The population is undergoing genetic drift. E) There has been a high rate of mutation of allele A to allele a. 19) What is the estimated frequency of allele a in the gene pool? A) 0.40 B) 0.60 C) 0.70 D) 0.18 E) 0.80 20) What proportion of the population is probably heterozygous (Aa) for this trait? A) 0.48 B) 0.72 C) 0.60 D) 0.36 E) 0.18

A B A

10) Two species of frogs belonging to the same genus occasionally mate, but the offspring do not complete development. What is the mechanism for keeping the two frog species separate? 10) ____ A) gametic isolation B) the postzygotic barrier called hybrid inviability C) the prezygotic barrier called hybrid sterility D) adaptation E) the postzygotic barrier called hybrid breakdown

B

14. The classic study of industrial melanism in the peppered moth A. illustrated the effects of gene flow between the color morphs on gene frequencies B. showed that natural selection could change gene frequencies C. provided the first evidence of sexual selection D. provided the first evidence for genetic drift E. provided the first illustration of the Hardy-Weinberg Rule

B

17. He placed different kinds of organisms on a continuum, or "scala naturae", of simple to complex, with humans at the pinnacle. A. Lamarck B Aristotle C. Buffon D. Linnaeus E. Lyell

B

24) What percentage of the population has type O blood? A) 0 B) 9 C) 10 D) 24 E) 48

B

25. A case of directional selection: in a population of butterflies composed of many red morphs and few yellow morphs, birds preferentially feed on the red morph and then switch once the number of yellow morphs begins to increase in the population. A. True B. False

B

26) In peas, a gene shows incomplete dominance for flower color such that RR = purple, Rr = pink, and r = white. In an isolated pea patch, a killing frost takes the population out of H/W equilibrium and leaves only 36 plants with white flowers, 7 with pink flowers, and 14 with purple flowers. What is the frequency of the recessive allele in the surviving population population? A) 0.31 B) 0.69 C) 0.63 D) 0.60 E) 0.37

B

26. When we say that one organism has a greater fitness than another individual of the same species, we specifically mean that the organism _____. A. competes for resources better B. leaves more living offspring C. lives longer D. mates more frequently E. none of the above

B

29. A recent trend seen in many plant species that are most susceptible to global warming is an increase in the number of tiny white hairs on leaves to increase leaf reflectivity and help cool leaves. This trend is an example of _____. A. a cline B. directional selection C. disruptive selection D. inheritance of acquired characteristics E. Bergman's rule

B

29. In a Hardy-Weinberg population with two alleles, T and t, that are in equilibrium, the frequency of the allele "t" is 0.7. What is the percentage of the population that is homozygous for this allele? A. 30 B. 49 C. 9 D. 3 E. 42

B

30. In a population of blue jays that is at Hardy-Weinberg equilibrium for two alleles for crest height, 16% of the population shows the recessive trait. What percent of the population show the dominant phenotype? A. 96% B. 84% C. 60% D. 48% E. 36%

B

34) In the mid-1900s, the Soviet geneticist Lysenko exposed winter wheat plants to ever-colder temperatures, collected their seeds, and then exposed the seedlings to ever-colder temperatures. He repeated his attempts over the course of decades in an attempt to evolve cold-tolerant winter wheat. Lysenko's attempts in this regard were most in agreement with the ideas of _______. A) Hutton B) Lamarck C) Cuvier D) Plato E) Darwin

B

35. In a population of flying spaghetti monsters, a single gene locus controls spaghetti-strand thickness. The allele T codes for thick spaghetti and is co-dominant with t, which codes for thin spaghetti (similar to a vermicelli, or perhaps angel-hair pasta? But I digress...). Heterozygotes have medium-thick spaghetti. The frequency of T in the population, which is at Hardy-Weinberg equilibrium, is 0.4. What should be the most common phenotype among flying spaghetti monsters? A. Thick flying spaghetti monsters B. Medium flying spaghetti monsters C. Thin flying spaghetti monsters D. It cannot be determined.

B

37. A trend toward the decrease in the size of plants on the slopes of mountains as altitudes increase is an example of ________. A. relative fitness. B. a cline. C. genetic drift. D. speciation. E. a bottleneck.

B

37. By itself (i.e., not necessarily Hardy-Weinberg equilibrium) the equation p + q = 1 tells us ____. A. the frequencies of alleles in a population are not changed by random mating B. the sum of the frequencies of two alternate alleles at a gene locus must total 1.0 C. genotype frequencies can be calculated if allele frequencies are known D. there are only two possible genotypes in a population E. a population that does not conform to this equation is evolving

B

41. In the population referred to in the two previous questions, what is the probability that a type O person and their type AB partner have a type A child (think!)? A. 0.0098 B. 0.0196 C. 0.0049 D. 0.0027 E. it cannot be determined

B

42. In Batesian mimicry, the fitness of the ______. A. palatable mimic is highest when the model species exists in low frequency B. palatable mimic is highest when the mimic exists in low frequency C. distasteful mimic is highest when the model species exists in low frequency D. distasteful mimic is highest when the mimic exists in low frequency E. none of the above

B

8. Body size in a species of gray mice shows clinal variation from north to south with northern mice having a larger phenotype than southern mice. If the clinal variation is due to genetic rather than environmental causes, then if I move a pregnant female from Boston to Tallahassee and allow her to give birth and raise her offspring here, how would I expect her offspring to compare to native mice born and bred here in Tallahassee? A. The Boston offspring will have a similar body size to Tallahassee mice. B. The Boston offspring will have a larger body size to Tallahassee mice. C. The Boston offspring will have a smaller body size to Tallahassee mice. D. The transplant study cannot work because the northern and southern populations cannot interbreed. E. The Boston mice will thoroughly embarrass the Yankees and go on to clobber to Colorado Rockies.

B

The allele for red flower color (R) in garden peas shows complete dominance over the allele for white flower color(r) at the same locus. In a population of peas you count 32 white flowered individuals and 168 red flowered plants. 16. Assuming that the population is in Hardy-Weinberg equilibrium, what is the most common genotype at the flower color locus? A. RR B. Rr C. rr 17. What fraction of the red flowered plants is heterozygous? A. 1 B. 0.48 C. 0.16 D. 0.98 E. 0.82

B .57

A. gametic B. temporal C. behavioral D. habitat E. mechanical 4) one species of carnation blooms in April and a second species of carnation blooms in June 4) _________ 5) male fairy shrimp of one species have long antennules to clasp a female when mating and a second species of fairy shrimp has short antennules to clasp females. 5) _________ 6) one species of crickets rapidly "chirp" to attract mates and a seconf species of cricket slowly "chirps" to attract mates 6) _________ 7) males of one species of finch bring nuptial ("wedding") presents of nuts to females prior to mating, whereas males of another finch species bring gifts of over-ripe fruit 7) _________ 8) a loblolly pine grows in rich, organic soils, but a sand pine grows best in well-drained sandy soils along the coast 8) _________ 9) females of one species of blackbird choose mates based on song quality; females of another species of balckbird choose mates on the basis of size 9) _________

B E C C D C

1) The ostrich and the emu look very similar and live in similar habitats, however they are not very closely related. This is an example of _______. A) sympatric speciation. B) divergent evolution. C) convergent evolution. D) exaptation. E) adaptive radiation.

C

1. The allele that causes sickle-cell anemia is maintained in some populations because of _____. A. frequency-dependent selection B. stabilizing selection C. heterozygote advantage D. gene flow E. genetic drift

C

14) Which example below will most likely guarantee that two closely related species will remain distinct biological species? (THINK CAREFULLY!) 14) ____ A) geographic isolation from one another B) convergent evolution C) reproductive isolation from one another D) colonization of new habitats E) hybridization

C

15) A defining characteristic of allopatric speciation is A) asexually reproducing populations. 15) ____ B) large populations. C) geographic isolation. D) artificial selection. E) the appearance of new species in the midst of old ones.

C

17) Which of the following would be an example of macroevolution? A) evolution of polymorphism in Papilio dardanus, with each morph mimicking a different protected butterfly B) evolution of antibiotic resistance in a strain of E. coli C) evolution of modern humans, Homo sapiens, from australopithecine ancestors D) replacement of a melanin-poor morph by a melanin-rich morph over many generations under conditions of increased UV exposure E) evolution of insecticide resistance in populations of insect pests treated through the years with DDT

C

18. Who developed the binomial system of naming organisms as part of his quest to discover order in the diversity of life? A. Aristotle B. Plato C. Linnaeus D. Darwin E. Cuvier

C

22) What is the frequency of the A allele? A) 0.632 B) 0.200 C) 0.500 D) 0.250 E) 0.400

C

24. Who was the naturalist who developed an hypothesis of evolution by natural selection independently of Darwin? A. Gregor Mendel B. Thomas Malthus C. Alfred Wallace D. Charles Lyell E. John Henslow

C

3) Which of the following is considered a post-zygotic barrier that serves to maintain reproductive isolation for a species? 3) _____ A) gametic incompatibility B) ecological isolation C) sterile offspring D) timing of courtship display E) geographic isolation

C

3. In a human population that is in Hardy-Weinberg equilibrium, the frequency of the IA allele is 0.5 and the frequency of the i allele is 0.3. All possible ABO blood groups are present in the population. What is the frequency of individuals with Type B blood? A. 0.55 B. 0.25 C. 0.16 D. 0.09 E. 0.05

C

30. In a Hardy-Weinberg population with two alleles, T and t, that are in equilibrium, the frequency of allele "t" is 0.7. What is the percentage of the population that is heterozygous for this allele? A. 9 B. 30 C. 42 D. 3 E. 21

C

31. Frogs are able to migrate freely among four ponds that are found close together in a section of the Apalachicola National Forest south of Tallahassee. Over time you would expect to see: A. frogs in some ponds better adapted overall than frogs in other ponds B. the pond-populations evolving into two or more separate species of frogs C. similar allele frequencies among pond-populations D. at least one pond-population going extinct E. none of the above

C

32) Which of the following is most likely to have been produced by sexual selection? A) bright colors of female flowers B) camouflage coloration in animals C) a male lion's mane D) different sizes of male and female pinecones E) the ability of desert animals to concentrate their urine

C

39. If a phenotypic polymorphism lacks a genetic component, then A. it must exhibit quantitative variation. B. the environment cannot affect its abundance. C. natural selection cannot act upon it to make a population better adapted over the course of generations. D. it cannot affect an individual's ability to survive. E all of the above.

C

4. In a population of fish, the smallest fish are eaten by crayfish and the largest fish are eaten by wading birds. Medium fish are too big for to be eaten by crayfish and too small for the birds to detect and grab as prey. What kind of selection is operating in this fish population? A. positive directional selection B. negative directional selection C. stabilizing selection D. disruptive selection E. frequency-dependent selection

C

40. In the population mentioned in the problem above, what is the least common blood type? A. Type A B. Type B C. Type AB D. Type 0 E. it cannot be determined

C

6. The allele frequency for fur color in a population of beach mice on Dauphin Island changed dramatically after Hurricane Katrina roared through that part of the Gulf coast and killed many of the beach mice. This is an example of ____. A. gene flow B. catastrophism C. a bottleneck event D. a founder effect E. frequency-dependent selection

C

9. All of the following are required for a population to reach Hardy-Weinberg equilibrium except ______. A. no natural selection B. a large population C. assortative mating D. no mutation E. no gene flow

C

9. The allele frequency at a flower color locus in a population of alpine plants changes when a landslide kills most of the individuals in the population. This is an example of _______. A. gene flow B. catastrophism C. a bottleneck effect D. Hardy-Weinberg equilibrium E. a founder effect

C

1. Which is true of vestigial traits? A. they have the same function in different species B. the are evidence of extinction C. they are caused by the environment rather than genetics D. they have no current function E. none of these is true of vestigial traits

D

10. All of the following would tend to maintain balanced polymorphism in a population except _____. A. disruptive selection B. frequency-dependent selection C. heterozygote advantage D. directional selection E. none of the above

D

15. Laboratory studies have shown that male fruit flies that exhibit uncommon courtship behaviors father more offspring because females prefer to mate with them. When these same behaviors are common in a population, males exhibiting them are no longer preferred. This scenario describes _____. A. positive assortative mating B. negative assortative mating C. stabilizing selection D. frequency-dependent selection E. heterozygote advantage

D

16. A natural theologian who studied organisms and assigned them to a hierarchy of taxonomic categories, including genus and species, based on shared similarities was _____. A. Lamarck B Aristotle C. Buffon D. Linnaeus E. Lyell

D

19. Which of the following does not serve as evidence for evolution? A. artificial breeding programs B. homologous structures C. comparative biochemistry D. analogous morphological structures E. comparative embryology

D

2) The correct sequence from the most to the least comprehensive of the taxonomic levels listed here is _______. A) kingdom, phylum, order, class, family, genus, and species. B) phylum, family, class, order, kingdom, genus, and species. C) phylum, kingdom, order, class, species, family, and genus. D) kingdom, phylum, class, order, family, genus, and species. E) family, phylum, class, kingdom, order, species, and genus.

D

2. In nature, if snow geese with the "blue" morph only mated with other "blue" morphs, and never with any "white" morph, this would be an example of _____. A. inbreeding B. random mating C. natural selection D. assortative mating E. frequency-dependent mating

D

20. In Australia, sugar gliders are small marsupial mammals that glide from tree to tree. In North America, flying squirrels are placental mammals that also glide from tree to tree. The similarities in morphology and lifestyle exhibited by these two types of animals are most likely the result of ________. A. descent with modification from a common ancestor B. genetic drift C. assortative mating D. convergent evolution E. a founder event

D

21. Batesian mimicry is when _______. A. two or more inedible species mimic each other B. two or more palatable species mimic each other C. an inedible species mimics a palatable species D. a palatable species mimics an inedible species

D

21. In a population of 100 alligators at Hardy-Weinberg equilibrium on the Wakulla River, 49 are homozygous dominant for bad breath (BB; not that you would get that close to notice!). The genotype frequency of alligators that are heterozygous for this trait in this population is ___. A. .49 B. 0.09 C. 0.51 D. 0.42 E. it cannot be determined

D

25) If there are 6,000 children born to this generation, how many would be expected to have type BB blood under the conditions of Hardy-Weinberg equilibrium? A) 40 B) 2,400 C) 960 D) 240 E) 100

D

28) Through time, the movement of people on Earth has steadily increased. This has altered the course of human evolution by increasing _______. A) nonrandom reproduction B) genetic drift C) geographic isolation D) gene flow E) mutations.

D

28. If two modern organisms are distantly related in an evolutionary sense, then one should expect that __________. A. they must live in very different habitats. B. they should be members of the same genus. C. they shared a common ancestor relatively recently. D. they should share fewer homologous structures than two more closely related organisms. E. their chromosomes should be very similar.

D

28. Sexual selection will ____. A. increase the size of individuals B. result in individuals better adapted to a particular environment C. result in a relative fitness (w) more than 1 D. select for traits that enhance an individual's chance of mating E. all of the above

D

29) When we say that an individual organism has a greater fitness than another individual, we specifically mean that the organism _______. A) lives longer than others of its species. B) competes for resources more successfully than others of its species. C) mates more frequently than others of its species. D) leaves more viable offspring than others of its species. E) utilizes resources more efficiently than other species occupying similar niches.

D

30) Which of the following statements best summarizes evolution as it is viewed today? A) It represents the result of selection for acquired characteristics. B) It is synonymous with the process of gene flow. C) It is the descent of humans from the present-day great apes. D) It is the differential survival and reproduction of the most fit phenotypes. E) It is goal-directed.

D

31) Cattle breeders have improved the quality of meat over the years by which process? A) directional selection B) artificial selection C) stabilizing selection D) A and B E) A and C

D

32. The existence of two or more distinct phenotypic forms in a species is known as ____. A. a population bottleneck B. stabilizing selection C. heterozygote advantage D. polymorphism E. directional selection

D

34. In a population of 10 rats in which fur color is controlled by a gene locus with two alleles, B and b, three of the rats are homozygous dominant at the locus, five are heterozygous, and the other two are homozygous recessive. What is the total number of alleles in the gene pool for this population with respect to the fur-color gene? A. 2 B. 5 C. 10 D. 20 E. It cannot be determined.

D

36. In a large, sexually reproducing population, the frequency of an allele changes from 0.6 to 0.2. From this change, one can most logically assume that, in this environment, ________. A. random processes have changed allelic frequencies. B. the allele mutates readily. C. the allele is neutral. D. the allele reduces fitness. E. there is no sexual selection.

D

36. Which is true of two analogous structures? A. They have the same developmental origin. B. They have no current function. C. They can be traced to a common ancestor. D. They serve similar functions. E. None of these is true.

D

37) DDT was once considered a "silver bullet" that would permanently eradicate insect pests. Today, instead, DDT is largely useless against many insects. What would need to be true for pest eradication efforts to have been successful in the long run? A) DDT application should have been continual. B) All habitats should have received applications of DDT at about the same time. C) Larger doses of DDT should have been applied. D) All individual insects should have possessed genomes that made them susceptible to DDT. E) The frequency of DDT application should have been higher.

D

38) Structures as different as human arms, bat wings, and dolphin flippers contain many of the same bones, these bones having developed from the same embryonic tissues. How do biologists interpret these similarities? A) by proposing that humans, bats, and dolphins share a common ancestor B) by the principle of convergent evolution C) by identifying the bones as being homologous D) A and C only E) A, B, and C

D

38. Several mice from Alabama with dark fur color float down the Apalachicola River on a tree branch and join a large population of mice in Florida in which nearly all the mice are light- colored. What mechanism of evolution does this scenario illustrate? A. a founder event B. a population bottleneck C. epistasis D. gene flow E. directional selection

D

39. In a population at Hardy-Weinberg equilibrium and where all possible blood types are present, the frequencies the IA allele is 0.20 and the frequency of the IB allele is 0.10. What fraction of this population would you expect to have type A blood (think!)? A. 0.20 B. 0.28 C. 0.04 D. 0.32 E. 0.08

D

5. Which of the following scenarios would most likely cause a population to evolve via genetic drift? A. a spontaneous change in the chromosome number in a population B. movement of individuals back and forth between neighboring populations C. negative assortative mating D. the initiation of a new population by a small number of individuals E. when the rarest phenotype in a population has the highest fitness

D

8. In a population in Hardy-Weinberg equilibrium, 25% of the individuals express the recessive phenotype. What is the expected frequency of heterozygotes? A. 0.05 B. 0.10 C. 0.25 D. 0.50 E. 0.75

D

11. A population geneticist determines that 98 of the 200 crayfish in a pond at Hardy-Weinberg equilibrium are heterozygous for the gene controlling antennal length where the allele coding for for long antennae (L) is dominant to the recessive allele for short antennae (l). The frequency of the recessive allele for this trait in this population is ____. A. 0.70 B. 0.51 C. 0.58 D. 0.76 E. It cannot be determined from this information

E

19. The inheritance of acquired characteristics was a major component of the evolutionary hypothesis proposed by whom? A. Aristotle B. Darwin C. Wallace D. Lyell E. Lamarck

E

21) All of the following are criteria for maintaining Hardy-Weinberg equilibrium involving two alleles except ____. A) there should be no natural selection. B) matings must be random. C) gene flow from other populations must be zero. D) populations must be large. E) the frequency of all genotypes must be equal.

E

23) What percentage of the population has type AB blood? A) 0 B) 40 C) 70 D) 10 E) 20

E

23. During a study session about evolution, one of your fellow students remarks, "The giraffe stretched its neck while reaching for higher leaves; its offspring inherited longer necks as a result." Which statement would you use to correct this student's misconception? A. Overproduction of offspring leads to a struggle for survival. B. Spontaneous mutations can result in the appearance of new traits. C. Only favorable adaptations have survival value. D. Disuse of an organ may lead to its eventual disappearance. E. Characteristics acquired during an organism's life are generally not passed on through genes.

E

23. Which of the following serve to introduce and/or maintain genetic variation in populations despite the trend for natural selection to increase the frequency only of the fittest individuals? A. epistasis B. mutation C. crossing over during meiosis D. A and B only E. A, B and C

E

26. During drought years on the Galapagos, small, easily eaten seeds become rare leaving only large, hard-cased seeds that only birds with large beaks can eat. If a drought persists for several years, then what should one expect to result from natural selection? A. Small birds mutating their beak genes with the result that later-generation offspring have larger beaks. B. Small birds gaining larger beaks by exercising their mouth parts. C. Small birds anticipating the long drought and eating more to gain weight and, consequently, growing larger beaks. D. Larger birds eating less so smaller birds can survive. E. More small-beaked birds dying than the larger-beaked birds. The offspring produced in subsequent generations have a higher percentage of birds with large beaks.

E

3. The forelimbs of modern vertebrates such as a human, a bird, and a bat provide a nice example of _____. A. the inheritance of acquired characteristics B. the idea that ontogeny recapitulates phylogeny C. convergent evolution D. vestigial organs E. descent with modification from a common ancestor

E

31. You sample a population of butterflies and find that 42% are heterozygous for a particular gene. What would be the frequency of the recessive allele in this population? A. 0.70 B. 0.30 C. 0.09 D. 0.49 E. Allele frequency cannot be estimated from this information.

E

35) Who was the naturalist who developed a concept of natural selection independently of Darwin? A) John Henslow B) Charles Lyell C) Thomas Malthus D) Gregor Mendel E) Alfred Wallace

E

38. The Darwinian fitness of an individual is measured by ________. A. how long it lives. B. its physical strength. C. the number of supergenes in the genotype. D. the number of mates it attracts. E. the number of its offspring that survive to reproduce.

E

40. The higher the proportion of loci that are "fixed" in a population, the lower is that population's ______. A. genetic diversity. B. heterozygosity. C. birth rate. D. A, B, and C E. A and B only

E

5. Which of the following is not an essential element of evolution by natural selection? A. more offspring are produced than can survive to become parents themselves B. individuals with some traits produce more offspring than others C. variation among individuals is caused by genetic differences D. there is variation among individuals of a species E. all of these are essential elements of evolution by natural selection

E

6. In a population that has just been reduced to a small size by a natural disaster (i.e., no longer in Hardy- Weinberg equilibrium), you find a total of 6 survivors. Four have the genotype AA, 1 is Aa, and 1 is aa. What is the frequency of the A allele in this gene pool? A. 0.25 B. 0.40 C. 0.50 D. 0.60 E. 0.75

E

7. Which of the following would be most likely to cause genetic drift? A. a spontaneous change in chromosome number in a population B. movement of individuals from one population to another C. the production of more offspring by brighter colored individuals D. a tendency of individuals to prefer to mate with their relatives E. the initiation of a new population by a small number of individuals

E

Choose among these options to answer the following questions. Each option may be used once, more than once, or not at all. A. random selection B. directional selection C. stabilizing selection D. disruptive selection E. sexual selection 41. Brightly colored peacocks mate more frequently than do drab peacocks. E 42. Fossil evidence indicates that horses have gradually increased in size over geologic time. B 43. The average birth weight for human babies is about 3 kg. C 44. A certain species of land snail exists as either a cream color or a solid brown color. Intermediate individuals are relatively rare. D 45. Pathogenic bacteria found in many hospitals are antibiotic resistant. B

E B C D B

A. frequency-dependent selection B. directional selection C. stabilizing selection D. sexual selection E. disruptive selection 12. A population of giant hissing cockroaches from Madagascar are pretty evenly divided among two strikingly different color patterns: very dark brown and very light golden. _____ 13. Male guppies with the flashiest longest fins mate more frequently than males with less showy fins. _____ 14. Farm-raised turkeys have been bred to now have disproportionately much more breast meat than wild turkeys. _____ 15. The pesticide malathion was once widely used but is now ineffective for mosquito control, as it fails to kill off these insects like it once used to. _____

E D B B

In a hypothetical population of 1,000 people, tests of blood-type genes show that 160 have the AA, 480 have the genotype AB, and 360 have the genotype BB. 32. What is the frequency of the A allele? A. 0.001 B. 0.100 C. 0.002 D. 0.600 33. What is the frequency of the B allele? A. 0.001 B. 0.400 C. 0.002 D. 0.600 34. What percentage of the population has type O blood? A. 24 B. 48 C. 60 D. 0 E. 0.400 E. 0.100 E. 10 35. If there are 4,000 children born to this generation, how many would be expected to have AB blood under the conditions of Hardy-Weinberg equilibrium? A. 2,400 B. 100 C. 1,920 D. 2,000 E. 960

E D D C