Question 1

Which experiment provided the first strong evidence that DNA, and not protein, is the genetic material in cells?

Accepted Answer

The Hershey-Chase experiment using bacteriophages labeled with radioactive sulfur and phosphorus

Question 2

If a DNA sample contains 30% adenine, what percentage of guanine would you expect to find in the sample?

Accepted Answer

$$20\%$$

Question 3

Which of the following best describes the process of transcription?

Accepted Answer

The synthesis of RNA from a DNA template

Question 4

A mutation changes a codon from UAU (tyrosine) to UAA (stop codon). What type of mutation is this?

Accepted Answer

Nonsense mutation

Question 5

Which of the following is a requirement for a population to be in Hardy-Weinberg equilibrium?

Accepted Answer

No migration into or out of the population

Question 6

Given the Hardy-Weinberg equation $$p^2 + 2pq$$ + $$q^2 = 1$, what does 2pq$ represent?

Accepted Answer

The frequency of heterozygous individuals in the population

Question 7

A population of 1000 individuals has 360 individuals with genotype AA, 480 with Aa, and 160 with aa. What is the frequency of allele a?

Accepted Answer

$$q = 0.4$$

Question 8

Which of the following scenarios best illustrates genetic drift?

Accepted Answer

A hurricane randomly kills most of a small island population, leaving only a few survivors

Question 9

Why is the sickle cell allele more common in regions where malaria is prevalent?

Accepted Answer

Heterozygotes for the sickle cell allele have increased resistance to malaria

Question 10

Which of the following is an example of a founder effect?

Accepted Answer

A small group of individuals colonizes a new island, and their descendants show different allele frequencies than the original population

Question 11

Which of the following statements about natural selection is TRUE?

Accepted Answer

Natural selection acts on heritable variation within a population

Question 12

In the context of human skin color evolution, what is the main evolutionary advantage of darker skin in equatorial regions?

Accepted Answer

Protection against DNA damage from high UV radiation

Question 13

Which of the following best describes a bottleneck effect?

Accepted Answer

A sharp reduction in population size due to a random event, leading to a loss of genetic diversity

Question 14

Which of the following is NOT a condition required for Hardy-Weinberg equilibrium?

Accepted Answer

Small population size

Question 15

A population is in Hardy-Weinberg equilibrium with $$p = 0.7$$ and $$q = 0.3. $$What is the expected frequency of heterozygotes?

Accepted Answer

$$2pq = 0.42$$

Question 16

Which of the following best explains why most harmful mutations are not eliminated from populations immediately?

Accepted Answer

Many harmful mutations are recessive and can persist in heterozygotes

Question 17

Which of the following is an example of convergent evolution?

Accepted Answer

Wings in bats and wings in birds

Question 18

Which of the following is a direct result of random genetic drift?

Accepted Answer

Allele frequencies change unpredictably from one generation to the next in small populations

Question 19

Why is it important for a genetic code to be redundant (degenerate)?

Accepted Answer

It reduces the impact of some mutations by allowing multiple codons to code for the same amino acid

Question 20

Which of the following best describes the difference between a synonymous and a non-synonymous mutation?

Accepted Answer

A synonymous mutation does not change the amino acid sequence, while a non-synonymous mutation does

General Biology II: Molecular Biology, Evolution, and Population Genetics Study Notes

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