Question 1

Which of the following statements correctly describes a key difference between DNA and RNA molecules?

Accepted Answer

DNA contains the base thymine, while RNA contains the base uracil.

Question 2

Which of the following best explains how genetic information is transmitted from one generation to the next in eukaryotes?

Accepted Answer

Genetic information is stored in DNA, which is replicated and passed to daughter cells during cell division.

Question 3

Which of the following is NOT a component of a nucleotide found in DNA?

Accepted Answer

A fatty acid tail

Question 4

Which of the following base pairings is correct for RNA?

Accepted Answer

Cytosine pairs with guanine

Question 5

Which of the following best describes the difference between purines and pyrimidines?

Accepted Answer

Purines include adenine and guanine, while pyrimidines include cytosine, thymine, and uracil.

Question 6

During DNA replication, in which direction is the new DNA strand synthesized?

Accepted Answer

$$5' \rightarrow 3'$$

Question 7

Which enzyme is responsible for unwinding the DNA double helix during replication?

Accepted Answer

Helicase

Question 8

In prokaryotic DNA replication, which of the following is true compared to eukaryotic DNA replication?

Accepted Answer

Prokaryotes have a single, circular chromosome, while eukaryotes have multiple, linear chromosomes.

Question 9

Which enzyme synthesizes the RNA primer required for DNA polymerase to begin replication?

Accepted Answer

Primase

Question 10

A mutation occurs that disables DNA ligase in a eukaryotic cell. What is the most likely consequence during DNA replication?

Accepted Answer

Okazaki fragments on the lagging strand will not be joined together.

Question 11

Which of the following best describes the role of topoisomerase during DNA replication?

Accepted Answer

It relieves the tension ahead of the replication fork by cutting and rejoining DNA strands.

Question 12

Which of the following is a similarity between DNA and RNA?

Accepted Answer

Both are composed of nucleotides with a phosphate group, a sugar, and a nitrogenous base.

Question 13

If a DNA strand has the sequence $$5'-ATCGGTA-3'$$, what is the complementary DNA strand?

Accepted Answer

$$3'-TAGCCAT-5'$$

Question 14

Which of the following is a key difference in the initiation of DNA replication between prokaryotes and eukaryotes?

Accepted Answer

Eukaryotes initiate replication at multiple origins, while prokaryotes typically have a single origin.

Question 15

A scientist is studying a virus that uses RNA as its genetic material. Which of the following statements is most likely true about this virus?

Accepted Answer

Its genetic material contains uracil instead of thymine.

Question 16

Which of the following best explains why DNA polymerase cannot initiate synthesis of a new DNA strand on its own?

Accepted Answer

DNA polymerase can only add nucleotides to an existing 3' hydroxyl group.

Question 17

Which of the following is a correct pairing of a purine and a pyrimidine in DNA?

Accepted Answer

Adenine and thymine

Question 18

During DNA replication, which enzyme removes RNA primers and replaces them with DNA nucleotides in prokaryotes?

Accepted Answer

DNA polymerase I

Question 19

A patient is diagnosed with a genetic disorder caused by a mutation in the gene encoding helicase. Which cellular process is most directly affected?

Accepted Answer

DNA replication

Question 20

Which of the following best describes the organization of DNA in eukaryotic cells?

Accepted Answer

DNA is linear and packaged with histone proteins in the nucleus.

Genetic Information: Structure, Transmission, and Replication

Study Guide - Practice Questions