Q: Which equation would you use to calculate the average percent of loci that are heterozygous in a population?

$$ \frac{\text{Number of heterozygous loci}}{\text{Total number of loci}} \times 100 $$

Question 1

Which of the following best explains why MRSA (Methicillin-resistant Staphylococcus aureus) became resistant to methicillin so quickly after its introduction?

Accepted Answer

MRSA bacteria mutated to produce a new protein for cell wall synthesis, which methicillin could not inhibit.

Question 2

Which of the following is an example of homology as shown in the provided images?

Accepted Answer

The similar bone structure in the forelimbs of humans, cats, horses, bats, and dolphins.

Question 3

A phylogenetic tree can be rotated around branch points without changing the relationships depicted. What does this mean for interpreting evolutionary relationships?

Accepted Answer

The order of taxa at the branch tips does not represent the sequence of evolution.

Question 4

Which equation would you use to calculate the average percent of loci that are heterozygous in a population?

Accepted Answer

$$ \frac{	ext{Number of heterozygous loci}}{	ext{Total number of loci}} 	imes 100 $$

Question 5

Which of the following best describes convergent evolution, as illustrated in the images?

Accepted Answer

Unrelated species independently evolve similar traits due to similar environmental pressures.

Question 6

In a population of fruit flies, the frequency of an allele for DDT resistance increased after widespread pesticide use. Which mechanism of evolution does this illustrate?

Accepted Answer

Natural selection

Question 7

Which of the following statements about genetic drift is correct?

Accepted Answer

Genetic drift is most significant in small populations and can lead to the fixation of harmful alleles.

Question 8

A sudden environmental change drastically reduces the size of a population. Which effect is most likely to occur?

Accepted Answer

The bottleneck effect, leading to a gene pool that may not reflect the original population.

Question 9

Which of the following is NOT a reason why natural selection cannot fashion perfect organisms?

Accepted Answer

Natural selection can create new traits from scratch.

Question 10

Which of the following best describes the relationship between genotype and phenotype?

Accepted Answer

Phenotype is the product of both inherited genotype and environmental influences.

Question 11

Which of the following is a real-world example of gene flow affecting adaptation to local environments?

Accepted Answer

Migration of banded snakes from the mainland maintains disadvantageous alleles for banding pattern on the islands.

Question 12

Which of the following equations represents the Hardy-Weinberg equilibrium for allele frequencies?

Accepted Answer

$$ p^2$ + 2pq + q^2$ = 1 $$

Question 13

Which of the following is a characteristic of homologous structures?

Accepted Answer

They have similar underlying anatomy due to common ancestry, but may serve different functions.

Question 14

Which of the following best describes the founder effect?

Accepted Answer

A few individuals become isolated from a larger population, resulting in different allele frequencies due to chance.

Question 15

Which of the following is true about phylogenetic trees?

Accepted Answer

They show patterns of descent, not phenotypic similarity.

Question 16

Which of the following is a source of genetic variation in populations?

Accepted Answer

Mutation, gene duplication, and sexual reproduction.

Question 17

Which of the following best describes the process of adaptive evolution?

Accepted Answer

Traits that enhance survival or reproduction increase in frequency over time due to natural selection.

Question 18

Which of the following is an example of a polyphyletic group as shown in the diagrams?

Accepted Answer

A group that includes two convergent descendants but not their common ancestor.

Question 19

Which of the following best explains why nucleotide variation rarely results in phenotypic variation?

Accepted Answer

Most differences occur in noncoding regions (introns) and do not affect protein sequence.

Evolution, Phylogeny, and Genetic Variation Exam #2

Guida di studio - Domande di pratica

Study guide - Flashcard