Final Exam Practice Quiz Questions Flashcards
In a population of organisms with 4 alleles, how many homozygous genotypes are possible? How many heterozygous genotypes are possible?
4; 6 3; 4 4; 10 4; 3 4; 4
4;6
A true-breeding black rabbit is crossed with a true-breeding white rabbit to produce an F1 generation of 15 individuals. If the black color trait is dominant, which of the following represents the expected phenotype of an F1 generation cross?
0 black rabbits, 15 white rabbits, 0 grey rabbits 0 black rabbits, 0 white rabbits, 15 grey rabbits 5 black rabbits, 3 white rabbits, 7 grey rabbits 15 black rabbits, 0 white rabbits, 0 grey rabbits 5 black rabbits, 5 white rabbits, 6 grey rabbits
15 black rabbits,
0 white rabbits,
0 grey rabbits
The pedigree shown here pertains to a trait due to a rare, X-linked recessive mutation.
Individual 1 has an affected father, but the genotypes and phenotypes of individuals 1–4 are unknown. What is the probability that individual 1 is heterozygous? What is the probability that individual 3 is heterozygous? What is the probability that individual 4 is affected?
1/2; 1/4; 1/4 1; 1/4; 1/2 1; 1/2; 1/4 1; 1/2; 1/2 1/2; 1/4; 1/2
1; 1/2; 1/2
Individual 1 is heterozygous if you assume the mother is affected. If the mutation is x linked recessive then the mother has both x mutations. So all female offspring would be heterozygous
Imagine the following genotype frequencies in a population: p2 = 0.49, 2pq = 0.42, q2 = 0.09. Now assume that there is nonrandom mating where individuals with one genotype will only mate with individuals that also have their genotype. Assume this pattern of mating goes on until the frequency of heterozygotes is effectively zero. What will the frequency of allele p be in the population?
0. 49 1. 0 0. 91 0. 3 0. 7
0.7
In some large groups of plants, including dandelions, oaks, and willows, the biological species concept is complicated because the process of _____ allows gene flow to occur between good _____ that can be easily distinguished based on appearance.
allopatric speciation; ring species hybridization; morphospecies polyploidy; evolutionary species polyploidy; ring species hybridization; ecological species
hybridization; morphospecies
How is it possible that phylogenies based on sequences from nuclear genomes and organellar genomes (i.e., chloroplasts and mitochondria) from the same group of species yield phylogenetic trees with different branching orders?
Nuclear and organellar genes evolved at different rates, obscuring evolutionary relationships. For organelles like chloroplasts, no mutations can occur or photosynthesis would stop and the organism would die. The nuclear genome can accumulate mutations, so it can continue to evolve. Transfer of genetic material from the genome of the endosymbiont to the host results in two phylogenies, host and endosymbiont. The host genome continues to accumulate mutations, but the endosymbiont genome cannot. The genome of the endosymbiont is more closely related to members of the group in which it originally evolved, while the nuclear genome of the engulfing organism has its own evolutionary trajectory.
The genome of the endosymbiont is more closely related to members of the group in which it originally evolved, while the nuclear genome of the engulfing organism has its own evolutionary trajectory.
endosymbiont: when one cell lives within another cell
Why:
Consider the data in Figure 46.11 illustrating the survivorship curve of the lime swallowtail butterfly. As indicated in your text, the survivorship from the egg to larval stage is 68%. Calculate the survivorship from the larval to pupal stage.
93% (0.93) 68% (0.68) 45% (0.45) 40% (0.40)
93% (0.93)
Tropical leafcutter ants collect leaf cuttings which they transport to special underground chambers. There, they chew the leaves to create nursery beds on which they grow a species of fungus they use for food. When ant queens disperse to establish new colonies, they carry the fungus with them, dispersing it as well (this benefits the fungus). In the ants’ nest, the fungus is at risk of being destroyed by another fungal species that is able to grow in the same habitat, using the same limited resources. On their bodies, the ants carry and provide a home for bacteria that produces antibiotics the ants use to kill this second fungus and thereby protect their food supply. In this system, the relationship between the leafcutter ants and their fungal food species is:
interspecific competition. predation. commensalism. mutualism. parasitism.
mutualism.
Tropical rainforests have high species richness of trees. Which of the following statements provides the MOST reasonable explanation why animal species richness is also high in tropical rainforests?
Animals are unable to adapt to climate variability in higher latitudes. Animals have had the same amount of time to evolve in rainforest areas as trees. Animals have diversified into the vast number of niches provided by tree diversity. Animal diversification rates are higher than those of trees.
Animals have diversified into the vast number of niches provided by tree diversity.
Some biologists believe that the latitudinal gradient in species diversity reflects the fact that high latitudes recently lay beneath large glaciers. If there had been no recent ice age, would we still expect to see a latitudinal diversity gradient?
Yes, with or without recent glaciation of high latitudes, there is still less energy available at high latitudes to support diverse biomes. No, without the ice ages, biomes at high latitudes would be older, with more time for the diversification of species. Yes, nutrient availability would still be lower at high latitudes. No, without polar ice (large ice formation around the pole), warm ocean currents like the Gulf Stream would carry more heat to high latitudes, making them more productive and, so, supporting more diversity.
Yes, with or without recent glaciation of high latitudes, there is still less energy available at high latitudes to support diverse biomes.
Why:
Glaciers accentuate the latitudinal gradient in climate, but this is fixed by basic features of Earth’s curvature and orbit. Thus, to the extent that primary production and seasonality influence species diversity, a latitudinal gradient would still exist. Consistent with this, paleontological studies of species diversity during warm epochs when there were no polar ice caps still show that more species resided at low latitudes
Examine Figure 49.1 below illustrating human population growth. What pattern of growth are we currently exhibiting?
logistic growth None of the answer options is correct. intrinsic growth geometric growth exponential growth
exponential growth
Many endangered species of birds in Hawaii are in danger of contracting avian malaria from mosquito bites. Many of these bird species live in the higher elevations of mountains in Hawaii, where it is too cold for the mosquitoes to exist. If global warming continues at the current estimated pace, what would you expect to happen to the distribution of these bird species?
Their distribution will remain the same, but their population size will decrease. Their distribution will increase because mosquitoes will die in the warmer regions. Their distribution will decrease to areas of even higher elevation.
Their distribution will decrease to areas of even higher elevation.
Based on the figure below, which of the following statements is/are a direct reflection of the data presented? (Select all that apply.)
In 2010 illegal killing rates surpassed natural mortality rates of elephants. Natural mortality rate is higher than the illegal killing rate of elephants between 1998 and 2006. Increasing ivory prices always increases the amount of illegal killing of elephants. After 2008, increasing ivory prices are coincident with increases in illegal killing of elephants.
In 2010 illegal killing rates surpassed natural mortality rates of elephants.
After 2008, increasing ivory prices are coincident with increases in illegal killing of elephants.
Shown here are two alleles of an SNP, one of which is associated with a higher risk of developing high blood pressure (hypertension).
Normal allele:
5’ -ATTCGCGGAATTCTGG -3’
3’ -TAAGCGCCTTAAGACC -5’
Allele associated with hypertension:
5’-ATTCGCGGGATTCTGG- 3’
3’-TAAGCGCCCTAAGACC -5’
You amplify DNA from multiple patients at a cardiologist’s office and digest each with EcoRI in order to determine the patients’ genotypes for this SNP. EcoRI recognizes the sequence below and cuts each strand at the locations indicated by the arrows.
Which lane in the gel below which lane represents an individual homozygous for the hypertension allele?
lane A lane D lane B lane C lane E
lane A
Why: there should only be one band because they is only one cuts being made because of the hypertension.
Among the progeny of a heterozygous round (Aa) × homozygous wrinkled (aa) testcross, three seeds are chosen at random. What is the probability that all three seeds are round?
3(1/2)3 2(1/2)3 (1/2)3 4(1/2)3
(1/2)3
