Question 1

Which experimental result from the Meselson-Stahl experiment provided the strongest evidence for semiconservative DNA replication?

Accepted Answer

After one generation in light nitrogen, DNA showed a single intermediate-density band.

Question 2

What is the primary function of DNA helicase during DNA replication?

Accepted Answer

It unwinds the double helix using ATP, separating the two DNA strands.

Question 3

Why does DNA polymerase require a primer to begin DNA synthesis?

Accepted Answer

DNA polymerase can only add nucleotides to a free 3'-OH group.

Question 4

Which enzyme is responsible for removing RNA primers and filling in the resulting gaps with DNA during lagging strand synthesis?

Accepted Answer

DNA polymerase

Question 5

What is the role of topoisomerase during DNA replication?

Accepted Answer

It relieves torsional strain by transiently breaking and rejoining DNA.

Question 6

Which of the following best describes the difference between leading and lagging strand synthesis?

Accepted Answer

The leading strand is synthesized continuously toward the replication fork, while the lagging strand is synthesized in short fragments away from the fork.

Question 7

Which of the following equations correctly represents the direction of DNA synthesis?

Accepted Answer

$$5' \rightarrow 3'$$

Question 8

What is the function of single-strand binding proteins (SSB) during DNA replication?

Accepted Answer

They prevent the separated DNA strands from reannealing.

Question 9

Which of the following statements about Okazaki fragments is correct?

Accepted Answer

They are joined together by DNA ligase.

Question 10

In eukaryotic cells, which DNA polymerase is primarily responsible for synthesizing the leading strand?

Accepted Answer

DNA polymerase ε

Question 11

Which of the following best explains why eukaryotic chromosomes have multiple origins of replication?

Accepted Answer

Multiple origins allow the entire genome to be replicated efficiently within the time constraints of the cell cycle.

Question 12

What is the main role of DNA ligase during DNA replication?

Accepted Answer

It seals nicks in the sugar-phosphate backbone between Okazaki fragments.

Question 13

Which of the following is a direct consequence of the antiparallel nature of DNA strands during replication?

Accepted Answer

One strand is synthesized continuously and the other discontinuously.

Question 14

Which enzyme is responsible for proofreading newly synthesized DNA and correcting mismatched bases?

Accepted Answer

DNA polymerase

Question 15

During DNA replication, which of the following provides the energy for the formation of new phosphodiester bonds?

Accepted Answer

Hydrolysis of dNTPs

Question 16

Which of the following best describes the role of nucleosomes during eukaryotic DNA replication?

Accepted Answer

Nucleosomes are reorganized, and histones are recycled and deposited on daughter DNA.

Question 17

Which of the following statements about the directionality of DNA polymerase activity is correct?

Accepted Answer

DNA polymerase synthesizes DNA in the $$5' \rightarrow 3'$$ direction.

Question 18

Which of the following is NOT a function of the sliding clamp during DNA replication?

Accepted Answer

It unwinds the DNA double helix.

Question 19

Which of the following best explains why Okazaki fragments are formed during DNA replication?

Accepted Answer

DNA polymerase can only synthesize DNA in the $$5' \rightarrow 3'$$ direction, but the two template strands are antiparallel.

Week 6

Study Guide - Practice Questions

Study Guide - Flashcards