AP Bio Unit 7

allopatric speciation

A geographic barrier becomes present, separating the parent population. The barrier can create two different environments, which could make the species evolve, potentially leading to two different species.

Based on morphological characteristics, the phylogenetic tree above has been developed for species I, II, III, and IV. D N A sequencing has recently been completed for a particular gene found in all four species. The sequencing will provide additional information for answering which of the following questions?

Are species III and IV the most closely related?

The validity of the cladogram is best supported by molecular evidence for which of the following changes in the amino acid composition of the beta-hemoglobin protein during the evolution of these species?Ciprofloxacin is given as an antibiotic to healthy livestock to promote efficient weight gain. Strains of the bacterium Campylobacter jejuni naturally colonize the digestive tracts of livestock, and the C. jejuni can be transferred to people through the handling and consumption of contaminated meat. People infected with C. jejuni also are treated with ciprofloxacin. Which of the following is the most likely consequence of adding ciprofloxacin to animal feed?

Ciprofloxacin-resistant strains of C. jejuni will have a selective advantage in the digestive tracts of livestock, increasing the risk of serious infections in people.

Which of the following is most likely to create genetic variation in a population?

DNA polymerase errors during replication

A researcher released large numbers of moths into different environments in an attempt to better understand a mechanism of evolution. The moths were released in four trials as described in the table above. Each of the released moths had a small mark on the underside of a wing for identification. After an appropriate amount of time, the researcher recaptured as many of the released moths as possible. Data from the experiment are included in the table above. Which of the following claims is best supported by the data?

Dark-colored moths were more likely to be recaptured in the polluted environment than in the unpolluted environment, suggesting an increased chance of reproductive success.

Which of the following scientific questions will best help researchers determine when the nontaster allele arose in the evolutionary history of the selected primates?

Does the nontaster allele exist in any nonhuman primate populations?

Toxic substances often have a bitter taste that causes animals who try to eat such substances to spit them out rather than swallow them. Additional data suggest that gorilla populations have a very low frequency of nontasters. Which of the following best describes the likely evolution of the TAS2R38 locus in the gorilla population?

Gorillas who could taste bitter toxins were more likely to survive and reproduce than nontasters

punctuated equilibrium

Long periods of stability are interrupted suddenly by a major disruption that causes a mass extinction of existing species to occur

Refer to the information included above. Group I of the cladogram most likely includes which of the following species?

P and S only

To determine the evolutionary history and relationships among organisms, scientists gather evidence from a wide variety of sources including paleontology, embryology, morphology, behavior, and molecular biology. A phylogenetic tree of vertebrates is shown. Which of the following statements is most consistent with the phylogenetic tree shown?

The common ancestor of reptiles, birds, and mammals produced amniotic eggs.

The TAS2R38 receptor protein has been detected on the surface of cells from individuals who are homozygous for the nontaster allele of the TAS2R38 gene. Which of the following is the most likely effect of the mutations associated with the nontaster allele on TAS2R38 gene expression?

The mutations alter the primary structure of the encoded receptor protein

gradualism

The theory that evolution occurs slowly but steadily

p+q=1 P = ??

dominant allele frequency

Change in allele frequency =

evolution is occurring

p² + 2pq + q² = 1 2pq = ??

heterozygous frequency

p² + 2pq + q² = 1 p² = ??

homozygous dominant frequency

p² + 2pq + q² = 1 q² = ??

homozygous recessive frequency

No change in allele frequency =

no evolution is evident

p+q=1 q = ??

recessive allele frequency

In order to be a species, organisms must be able to produce ...

viable, fertile offspring