Biology 1009 Final Exam Quiz Questions Flashcards
Evolution…
A. must happen, due to organisms’ innate desire to survive.
B. can happen whenever any of the conditions for Hardy-Weinberg equilibrium are not met.
C. must happen whenever a population is not well-adapted to its environment.
D. requires that populations become better suited to their environments.
B
The concept of “Fitness” is described as the…
A. likelihood of an individual contributing fertile offspring to the next generation.
B. relative likelihood that more females will die than males in the population.
C. relative likelihood that one genotype will contribute to the gene pool of the next generation compared with other genotypes.
D. all of the above are true.
D
In a population of squirrels, fur color varies from a light shade, almost white, to a very dark brown. If changes in the environment resulted in decreased predation of individuals with the lightest coloration, which type of natural selection would you expect to occur? A. Diversifying selection. B. Stabilizing selection. C. Directional selection. D. Balancing selection.
C
In peas, a gene controls flower color such that R = purple and r = white. R is dominant to r. In an isolated pea patch, there are 36 purple-flowering plants and 64 white-flowering plants. Assuming Hardy-Weinberg equilibrium, what is the allele frequency of “r” for this population?
A. 0.36
B. 0.64
C. 0.75
D. 0.80
D
Natural selection changes allele frequencies because some ________ survive and reproduce more successfully than others…
A. individuals
B. alleles
C. loci
D. gene pools
A
Members of two different species possess a similar-looking structure that they use in a similar way to perform about the same function. Which of the following would suggest that the relationship more likely represents homology instead of convergent evolution?
A. The structures in adult members of both species are similar in size.
B. Both species are well adapted to their particular environments.
C. The two species also live in similar habitats.
D. The two species share many proteins in common, and the nucleotide sequences that code for these proteins are almost identical.
D
Which of the following must be true of a population before the population can evolve in response to natural selection?
A. There must be genetic variation among individuals.
B. The population must exhibit sexual reproduction.
C. The population must have predators.
D. The population must have recently colonized a new environment.
A
A test question for your midterm exam states, “The elephant stretched its nose while reaching for higher leaves; therefore its offspring inherited longer noses.” Which statement is most likely to be helpful in correcting this misconception?
A. Spontaneous mutations can result in the appearance of new traits.
B. Disuse of an organ may lead to its eventual disappearance.
C. Only favorable adaptations have survival value.
D. Characteristics acquired during an organism’s life-time are not passed on through the genes.
D
In a Hardy-Weinberg population with two alleles, “A” and “a”, that are in equilibrium, the frequency of the allele “a” is 0.3. What is the percentage of the population that is homozygous for this allele?
A. 9.0
B. 0.9
C. 0.09
D. 0.49
A
In the formula for determining a population’s genotype frequencies, the 2 in the term 2pq is necessary because….
A. heterozygotes have two alleles.
B. the population is doubling in number.
C. heterozygotes can come about in two ways.
D. the population is diploid.
C
There are two alleles, B and b, at a gene locus in a population at Hardy-Weinberg equilibrium. The relative frequency of the dominant (B) allele is 0.7. What is the expected number of heterozygous individuals if the total population size is 500 individuals?
A. 150
B. 210
C. 350
D. 420
B
Given a population that contains genetic variation, what is the correct sequence of the following events, under the influence of natural selection?
1: Well-adapted individuals leave more offspring than do poorly adapted individuals.
2: A change occurs in the environment.
3: Genetic frequencies within the population change.
4: Poorly adapted individuals have decreased survivorship.
A. 4 → 2 → 1 → 3
B. 2 → 4 → 1 → 3
C. 4 → 1 → 2 → 3
D. 2 → 4 → 3 → 1
B
Which of the following must be true of a population before the population can evolve in response to natural selection?
A. There must be genetic variation among individuals.
B. The population must exhibit sexual reproduction.
C. The population must have predators.
D. The population must have recently colonized a new environment.
A
If two modern organisms are distantly related in an evolutionary sense, then one should expect that…
A. they live in very different habitats.
B. they should share fewer homologous structures than two more closely related organisms.
C. their chromosomes should be very similar.
D. they shared a common ancestor relatively recently.
B
Artificial selection is the process by which…
A. individuals in wild populations randomly mate.
B. humans prevent natural selection.
C. natural selection fails to act in wild populations.
D. humans allow only organisms with specific characteristics to breed.
D