Biology Exam 4 practice questions

The gene for red-green color vision is on the X chromosome. Color-blindness is caused by a recessive allele. A normal woman (XNXN) marries a color-blind man (XnY). What fraction of their children will be color-blind? (Make a 2 by 2 chart) a. 0/4 b. 1/4 c. 2/4 d. 3/4

a. 0/4

In a cross of Aa Bb cc X Aa Bb Cc, what is the probability of obtaining an individual with the genotype AA Bb Cc? a. 1/16 b. 3/16 c. 1/64 d. 3/64

a. 1/16

Taxonomy is based on putting organisms into monophyletic groups. Which kingdom contains organisms that should be split into several kingdoms? a. Protista b. Plantae c. Fungi d. Animalia

a. Protista

Which of these is an example of natural selection? a. There is a species of moth that occurs in shades of gray that vary from very light gray to dark gray. This species often sits on the trunks of trees. The medium and dark gray moths blend in very well, but the very light gray moths are easy to see. As a result most of them get eaten by predators before they can reproduce. Over time, the number of light gray moths in the population has decreased and the number of darker moths has increased. b. The ancestor of modern corn had a few, tiny kernels on each ear. Humans selected plants with the most and biggest kernels and used the seeds from these plants to plant their next year's crops. Over a number of years of doing this corn plants were modified into what we know today. c. The ancestor of the domestic dog was the wolf. Humans took wolves and bred those individuals that had certain desirable traits. After thousands of years of selectively breeding for certain traits we now have dog varieties that are as different as poodles and St. Bernards. d. All of these are examples of natural selection

a. There is a species of moth that occurs in shades of gray that vary from very light gray to dark gray. This species often sits on the trunks of trees. The medium and dark gray moths blend in very well, but the very light gray moths are easy to see. As a result most of them get eaten by predators before they can reproduce. Over time, the number of light gray moths in the population has decreased and the number of darker moths has increased.

Homologous structures a. are structures in two or more species that originate as the same structure in a common ancestor b. are structures that look the same in different species c. cannot serve different functions in different species d. must serve different functions in different species

a. are structures in two or more species that originate as the same structure in a common ancestor

The modern dog is descended from wolves. Humans selected animals with particular traits and bred them. This is an example of __________. a. artificial selection b. natural selection c. convergent evolution d. adaptive radiation

a. artificial selection

Which of the following PREVENTS two populations from becoming different? a. gene flow b. genetic drift c. natural selection d. nonrandom mating

a. gene flow

Prezygotic isolating mechanisms include all of the following except a. hybrid sterility b. courtship rituals c. habitat separation d. seasonal reproduction

a. hybrid sterility

If you see the genotype Dd you know that this individual _______________. a. is heterozygous for this trait b. displays both the recessive and dominant traits c. is homozygous recessive for this trait d. is homozygous dominant for this trait

a. is heterozygous for this trait

Which of these is the best description of a dominant allele? a. It is the allele that is expressed. b. It is the most common allele. c. It is the best allele. d. both b and c

a. it is the allele that is expressed

What percent of the population in the last question is heterozygous? (Hardy one with 2 alleles and q=0.3 what percent is homozygous dominant one) a. 70% b. 42% c. 49% d. 21%

b. 42%

In guinea pigs there is a gene that codes for hair length. Short hair (S) is dominant to long hair (s). Another gene codes for curly hair. Curly (C) is dominant to straight (c). If a guinea pig has the genotype SsCc, what gametes could it produce? a. Ss and Cc b. SC, Sc, sC, and sc c. S, s, C, and c d. SS, CC, ss, and cc

b. SC, Sc, sC, and sc

Cephalization means that an animal has _________. a. a tail b. a brain c. sexual reproduction d. a coelom

b. a brain

In a testcross an individual of unknown genotype is crossed with ________ . a. a homozygous dominant individual b. a homozygous recessive individual c. a heterozygous individual d. an individual lacking the gene

b. a homozygous recessive individual

A clade is __________. a. a group of interbreeding individuals b. a taxonomic group c. any group that is heterotrophic d. any group that is haploid

b. a taxonomic group

Gaps in the fossil record a. demonstrate our inability to date geological sediments b. are expected since the probability that any organism will fossilize is extremely low c. have not been filled in as new fossils have been discovered d. weaken the theory of evolution

b. are expected since the probability that any organism will fossilize is extremely low

A coelom is a __________. a. reproductive structure of fungi b. body cavity lined with mesoderm c. structure that protects the brain d. backbone

b. body cavity lined with mesoderm

Stomata allow plants to ________. a. reproduce b. diffuse gas and water c. attach to the soil d. move nutrients from the roots to leaves

b. diffuse gas and water

Two closely related beetle species can produce hybrid offspring in the laboratory but in their natural environment they don't. This is because the one species lives up in oak trees and the other species lives on the ground. Because they live in different parts of the environment the two species don't come in contact with each other. This is an example of _________. a. temporal isolation b. ecological isolation c. mechanical isolation d. behavioral isolation

b. ecological isolation

The possession of fine fur in 5-month human embryos indicates a. that the womb is cold at that point in pregnancy b. humans evolved from a hairy ancestor c. hair is a defining feature of mammals d. some parts of the embryo grow faster than others

b. humans evolved from a hairy ancestor

Allopatric speciation a. is less common than sympatric speciation b. involved geographic isolation of some kind c. is the only kind of speciation that occurs in plants d. requires polyploidy

b. involved geographic isolation of some kind

An organism's __________ is/are determined by its ____________. a. genotype; phenotype b. phenotype; genotype c. alleles; phenotype d. genes; alleles

b. phenotype; genotype

In humans eye color is determined by several genes and eye color can vary from very light blue to very dark brown. This is an example of a trait coded for by ________. a. pleiotropic genes b. polygenes c. codominant genes d. incomplete dominance

b. polygenes

In Alabama there are many species of treefrog that breed at the same time. Sometimes a mistake happens and a male of one species fertilizes the eggs of a female belonging to another species. The hybrid youngster grows up and does well. When it becomes an adult other treefrogs don't want to mate with it. This is an example of _________. a. temporal isolation b. postzygotic isolation c. gametic isolation d. mechanical isolation

b. postzygotic isolation

A couple gets married and decides to have 3 children. What is the probability that all three will be girls? a. 3 x ½ b. ½ x ½ x ½ c. ½ d. 1/4 x 1/4 x 1/4

b. ½ x ½ x ½

If a man with type AB blood marries a woman with type O blood, what proportion of their children will have type A blood? (Make sure you write the alleles correctly) (Make a chart thing) a. none b. 1/4 c. ½ d. all

c. 1/2

The F1 plants from the previous question (PP x pp)=(all purple) are allowed to self fertilize. The phenotypic ration for the F2 should be a. all purple b. 1 purple: 1 white c. 3 purple: 1 white d. 3 white: 1 purple

c. 3 purple: 1 white

When you cross true-breeding tall and short tobacco plants you get an F1 that is intermediate in height. When this F1 is self-crossed, it yields an F2 with a continuous distribution of heights. What is the best explanation for these data? a. Height is determined by a single gene with incomplete dominance b. Height is determined by a single gene with many alleles c. Height is determined by the additive effects of many genes d. Height is determined by epistatic genes

c. Height is determined by the additive effects of many genes

Which of the following is NOT a characteristic of fungus? a. cell walls made of chitin b. a form of mitosis different from plants and animals c. ability to conduct photosynthesis d. filamentous structure

c. ability to conduct photosynthesis

A tetrapod is a type of __________. a. plant b. fungus c. animal d. protist

c. animal

How is the process of natural selection different from that of artificial selection? a. natural selection produces more variation b. natural selection makes an individual better adapted c. artificial selection is a result of human intervention d. artificial selection results in better adaptations

c. artificial selection is a result of human intervention

You have _______ symmetry and are a(n) __________. a. radial; vertebrate b. radial; invertebrate c. bilateral; vertebrate d. bilateral; invertebrate

c. bilateral; vertebrate

Which of these groups is often lumped into the Reptiles? a. fish b. amphibians c. birds d. mammals

c. birds

Hyphae are found in ________________. a. protists b. bacteria c. fungi d. plants

c. fungi

In a small rodent species the genotype CBCB codes for black fur, the genotype CWCW codes for white fur, and the genotype CBCW codes for gray fur. This is an example of ___________. a. pleiotropy b. codominance c. incomplete dominance d. a sex-linked trait

c. incomplete dominance

If an allele has multiple effects it is _____________. a. a polygene b. codominant c. pleiotropic d. an autosome

c. pleiotropic

The first group to undergo mitosis was the __________. a. plants b. bacteria c. protists d. fungi

c. protists

If 70% (= 0.7) of the alleles for height in a plant species are T and 30% are t, what percentage of the population is tt? a. 30% b. 0.7 x 0.3 = 0.21 = 21% c. 0.3 + 0.3 = 0.6 = 60% d. 0.3 x 0.3 = 0.09 = 9%

d. 0.3 x 0.3 = 0.09 = 9%

If you cross 2 SsCc parents from the last question(the guinea pig), how many youngsters would have long, straight hair? (Make a 4 by 4 chart) a. 9/16 b. 8/16 c. 3/16 d. 1/16

d. 1/16

Japanese four o'clocks that are red and tall are crossed to white short ones, producing an F1 that is pink and tall. If these genes assort independently, and the F1 is self-crossed, what would you predict for the ratio of F2 phenotypes? a. 3 red tall: 1 white short b. 1 red tall: 2 pink short: 1 white short c. 3 pink tall: 6 red tall: 3 white tall: 1 pink short: 2 red short: 1 white short d. 3 red tall: 6 pink tall: 3 white tall: 1 red short: 2 pink short: 1 white short

d. 3 red tall: 6 pink tall: 3 white tall: 1 red short: 2 pink short: 1 white short

In a population of red (dominant allele) or white flowers in Hardy-Weinberg equilibrium, the frequency of red flowers is 91%. What is the frequency of the red allele? a. 9% b. 30% c. 91% d. 70%

d. 70%

Tall (T) is dominant to short (t) and yellow flower (Y) is dominant to white (y). If you cross a TtYy individual with a TtYy individual what proportion of the offspring will be tall with yellow flowers? (You don't need a Punnett square to answer this) a. 0/16 b. 1/16 c. 3/16 d. 9/16

d. 9/16

Which of these is an example of allopatric speciation? a. A small group of fruit flies from the U.S. mainland somehow got to Hawaii. The fruit and climate in their new home was different than what they had experienced on the mainland. Over time this population of fruit flies on Hawaii adapted to the local environment. During the process a number of changes occurred in the Hawaiian fruit flies and they eventually became a new species. b. A species of insect was accidently transported from South America to Australia. The transported insects did well in their new home and adapted to the local conditions. After many years they had changed sufficiently to be considered a different species than the insects in South America. c. A small group of iguanid lizards from Ecuador made it out to the Galapagos Islands. Once they made it to the islands they quit eating leaves and started eating seaweed. They became adapted for swimming in the ocean and made a number of other changes in their anatomy, behavior, and ecology. After many years, this group of lizards became a species that was quite different from its ancestors in Ecuador. d. All of these are examples of allopatric speciation.

d. All of these are examples of allopatric speciation.

For natural selection to result in evolutionary change a. variation must exist in a population b. reproductive success of different phenotypes must differ c. variation must be inherited from one generation to the next d. all of the choices are correct

d. all of the choices are correct

Symbiotic relationships occur between the fungi and a. plants b. bacteria c. animals d. all of the choices are correct

d. all of the choices are correct

A population's gene frequency should NOT change if ____________. a. the population is large b. there is random mating c. there is no natural selection d. all of these

d. all of these

Gametophytes _________. a. are haploid b. make gametes c. a type of plant d. all of these

d. all of these

Select the characteristic that is found in all chordates at some time in life. a. notochord b. postanal tail c. pharyngeal gill slits d. all of these

d. all of these

Which of the following groups is made up of single celled organisms? a. Archaea b. Bacteria c. Protista d. all of these

d. all of these

Which of these is an example of a prezygotic isolating mechanism? a. Two closely related species of insects occur in the same place, but one lives up in the trees and never spends time on the ground, the other species lives in the grass and never spends time in the trees. b. Two species of closely related mice occur in the same area. One of the species is active and reproduces at night while the other species is active and reproduces during the day. c. Several closely related salamander species that look very similar breed together in the same ponds. Each species has a unique set of courtship behaviors which prevent crossbreeding between related species. d. all of these

d. all of these

If you found a fossil for a modern organism next to the fossil of a dinosaur, this would a. argue against evolution by natural selection b. have no bearing on evolution by natural selection c. indicate that dinosaurs may still exist d. both b and c are correct

d. both b and c are correct

In which domain of life would you find only single-celled organisms? a. eukarya b. bacteria c. archaea d. both b and c are correct

d. both b and c are correct

The theory of evolution by natural selection is a good example of how science proceeds because a. it rationalizes a large body of observations b. it makes predictions that have been tested by a variety of approaches c. it represents Darwin's belief of how life has changed over time d. both b and c are correct

d. both b and c are correct

Genetic drift and natural selection can both lead to rapid rates of evolution. However, a. genetic drift works fastest in large populations b. only drift leads to adaptation c. natural selection requires genetic drift to produce new variation in populations d. both processes of evolution can be slowed by gene flow

d. both processes of evolution can be slowed by gene flow

Artificial selection is different from natural selection because a. artificial selection is not capable of producing large changes b. artificial selection does not require genetic variation c. natural selection cannot produce new species d. breeders (people) choose which individuals reproduce based on desirability of traits

d. breeders (people) choose which individuals reproduce based on desirability of traits

Artificial selection experiments in the laboratory such as figure 21.5 are an example of a. stabilizing selection b. negative frequency-dependent selection c. directional selection d. disruptive selection

d. disruptive selection

Allopatric species ____________. a. occur in the same place b. are closely related species c. are species that look alike d. do not occur in the same place

d. do not occur in the same place

Founder effects and bottlenecks are a. expected only in large populations b. mechanisms that increase genetic variation in a population c. two different modes of natural selection d. forms of genetic drift

d. forms of genetic drift

A mycelium is found in _____________. a. animals b. bacteria c. protists d. fungi

d. fungi

Phenotypes like height in humans, which show a continuous distribution, are usually the result of a. an alteration of dominance for multiple alleles of a single gene b. the presence of multiple alleles for a single gene c. the action of one gene on multiple phenotypes d. the action of multiple genes on a single phenotype

d. the action of multiple genes on a single phenotype

Suppose that the relationship between birth weight and infant mortality, instead of being at a minimum at intermediate sizes, changed such that babies born at 5 or 10 pounds had the highest survival, with a valley in between such that 7.5 pound babies had low survival rate. How would you expect the distribution of birth weights to change over time? a. it would not change b. The distribution would shift to the right c. the distribution would become bimodal, with two peaks and the mean value unchanged d. the distribution would become bimodal, with two peaks and the mean value shifted to the right.

d. the distribution would become bimodal, with two peaks and the mean value shifted to the right.

What is the probability of obtaining an individual with the genotype bb from a cross between two individuals with the genotype Bb? a. 1/2 b. 1/4 c. 1/8 d. 0

b. 1/4

Use the Hardy-Weinberg Equation to answer the next questions. If you have a gene with two alleles and q = 0.3 what percent of the population is homozygous dominant? a. 30% b. 70% c. (0.3)(0.3) = 0.09 = 9% d. (0.7)(0.7) = 0.49 = 49%

d. (0.7)(0.7) = 0.49 = 49%