Exam 4: Questions from Book

A fluid-filled cavity that develops completely with mesodermal tissue is a characteristic of a a. coelmate b. pseudocoelomate c. acoelmate d. all of the choices are correct

a

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

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

In animal sexual reproduction the gametes are formed by the process of a. meiosis b. mitosis c. fusion d. binary fission

a

stabilizing selection differs from directional selection because a. in the former, phenotypic variation is reduced but the average phenotype stays the same, whereas in the latter both the variation and the mean phenotype change b. the former requires genetic variation, but the latter does not c. intermediate phenotypes are favored in directional selection d. none of the choices is correct

a

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

b

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

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

In the figure, item A is the ______________ and item B is the ______________. a. complete digestive system; notochord b. spinal chord; nerve chord c. notochord; nerve cord d. pharyngeal slits; notochord

c

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 in 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

Which of the following characteristics is unique to all animals? a. sexual reproduction b. multicellularity c. lack of cell walls d. heterotrophy

c

Which of the following is NOT a characteristic of a 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

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

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 choice are correct

d

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

In a population of red (dominant allele) or white flowers in a 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

Japanese four o' clocks that are red and tall are crossed to white short ones, producing an F1 genotype 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: 1 tall white 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

Phenotypes like height in humans, which show a continuous distribution, are usually the result of a. an alternation 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

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

d

The evolution of bilateral symmetry was a necessary precursor for the evolution of a. tissues b. segmentation c. a body cavity d. cephalization

d

The possession of fine fur in 5 - month human embryo's 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

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

c

The F1 generation of the monohybrid cross purple (PP) x white (pp) The phenotype ratio for the F2 should be a. all purple b. 1 purple: 1 white c. 3 purple: 1 white d. 3 white: 1 purple

c

The F1 generation of the monohybrid cross purple (PP) x white (pp) flower pea plants should a. have all white flowers b. all have a light purple or blended appearance c. all have purple flowers d. have 3/4 purple flowers, and 1/4 white flowers

c

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

d