Q: Which formula would you use to calculate the percentage similarity between two DNA sequences if you know the number of matching base pairs and the total length of the sequence?

$$ \text{Percentage Similarity} = \frac{\text{Number of Matching Base Pairs}}{\text{Total Number of Base Pairs}} \times 100 $$

Question 1

Which of the following best explains why the arctic hare has shorter ears compared to the black-tail jackrabbit?

Accepted Answer

Shorter ears in arctic hares reduce heat loss, which is advantageous in cold environments.

Question 2

Which statement about natural selection is correct?

Accepted Answer

Natural selection acts on populations, not individuals, over many generations.

Question 3

A population of insects is exposed to a new pesticide. Over several generations, most individuals become resistant. Which type of selection is this an example of?

Accepted Answer

Directional selection

Question 4

Which of the following is NOT a line of evidence supporting evolution?

Accepted Answer

Seasonal migration patterns

Question 5

In a population, birthweight is an example of a trait under stabilizing selection. What does this mean?

Accepted Answer

Individuals with intermediate birthweights have higher survival rates than those with very low or very high birthweights.

Question 6

Which of the following best describes evolutionary fitness?

Accepted Answer

The ability of an organism to survive and reproduce in its environment.

Question 7

A mutation causes a seahorse to develop seaweed-like 'pods' that help it blend into its environment. Over time, this trait becomes common in the population. Which statement best explains this process?

Accepted Answer

The trait arose randomly and provided a survival and reproductive advantage, increasing its frequency in the population.

Question 8

Which type of selection favors individuals at both extremes of a trait, potentially leading to two distinct forms?

Accepted Answer

Disruptive (diversifying) selection

Question 9

Comparing the amino acid sequence of cytochrome c between humans and pigs shows only a few differences. What does this suggest about their evolutionary relationship?

Accepted Answer

Humans and pigs share a more recent common ancestor compared to species with more differences.

Question 10

Which of the following is an example of a vestigial structure?

Accepted Answer

The human appendix

Question 11

If a population of birds experiences a fluctuating environment where both very large and very small beaks are favored, what type of selection is occurring?

Accepted Answer

Disruptive selection

Question 12

Which formula would you use to calculate the percentage similarity between two DNA sequences if you know the number of matching base pairs and the total length of the sequence?

Accepted Answer

$$ 	ext{Percentage Similarity} = \frac{	ext{Number of Matching Base Pairs}}{	ext{Total Number of Base Pairs}} 	imes 100 $$

Question 13

Which method is used to compare evolutionary relationships by measuring the heat required to denature hybrid DNA strands from different species?

Accepted Answer

DNA hybridization studies

Question 14

Why are fibrinopeptides useful for studying recent evolutionary relationships?

Accepted Answer

They are not subject to strong natural selection and accumulate mutations rapidly.

Question 15

Which of the following statements about mutations and evolution is correct?

Accepted Answer

Mutations occur randomly and can provide variation for natural selection to act upon.

Question 16

Which evidence supports the idea that all aerobic eukaryotes share a common ancestor?

Accepted Answer

The presence of highly conserved cytochrome c proteins across species.

Question 17

A scientist compares mitochondrial DNA (mtDNA) between two individuals and finds only a few differences. What can be inferred?

Accepted Answer

The individuals share a recent common maternal ancestor.

Question 18

Which of the following is a correct inference from immunological studies comparing human and chimpanzee blood proteins?

Accepted Answer

High reactivity of anti-human antibodies with chimpanzee proteins suggests close evolutionary relationship.

Question 19

Which of the following is an example of a homologous structure?

Accepted Answer

The forelimbs of whales, bats, and humans

Question 20

If a population of foxes in a cold environment evolves thicker fur over generations, which evolutionary process is most likely responsible?

Accepted Answer

Natural selection favoring individuals with thicker fur

Chapter 22 Notes

Study Guide - Practice Questions

Study Guide - Flashcards