Question 1

Which of the following best describes the outcome of the classic Griffith experiment when heat-killed pathogenic bacteria were mixed with live non-pathogenic bacteria and injected into mice?

Accepted Answer

The mice died because the non-pathogenic bacteria became pathogenic by acquiring genetic material from the dead bacteria.

Question 2

Which of the following is NOT a component of a nucleotide?

Accepted Answer

A carboxyl group

Question 3

In the Hershey and Chase experiment, what was the key evidence that DNA, and not protein, was the genetic material?

Accepted Answer

Radioactive phosphorus was found inside the bacteria, indicating DNA entered the cells.

Question 4

Which of the following statements about the structure of DNA is TRUE?

Accepted Answer

The two strands of DNA run anti-parallel to each other.

Question 5

If a segment of double-stranded DNA contains 30% adenine, what percentage of guanine would you expect?

Accepted Answer

$20\%$

Question 6

During DNA replication, which enzyme is responsible for unwinding the double helix at the replication fork?

Accepted Answer

Helicase

Question 7

Which of the following best explains why DNA replication is described as 'semiconservative'?

Accepted Answer

Each new DNA molecule consists of one parental strand and one newly synthesized strand.

Question 8

Which of the following best describes the difference between a monomer and a polymer?

Accepted Answer

A monomer is a single subunit; a polymer is a chain of monomers linked together.

Question 9

Which of the following statements about Okazaki fragments is correct?

Accepted Answer

They are short segments of DNA synthesized on the lagging strand.

Question 10

During DNA replication, which enzyme is responsible for joining Okazaki fragments together?

Accepted Answer

DNA ligase

Question 11

Which of the following best describes the direction in which DNA polymerase synthesizes new DNA?

Accepted Answer

From the 5' end to the 3' end of the new strand

Question 12

Which of the following is a purine base found in DNA?

Accepted Answer

Adenine

Question 13

A scientist is studying DNA replication in E. coli. If the chromosome is circular and has a single origin of replication, how many replication forks will be present during replication?

Accepted Answer

Two

Question 14

Which of the following best explains why the lagging strand is synthesized discontinuously?

Accepted Answer

DNA polymerase can only add nucleotides to the 3' end, so synthesis must occur in short fragments as the fork opens.

Question 15

Which of the following is required for DNA polymerase to begin synthesizing a new DNA strand?

Accepted Answer

A free 3' hydroxyl group provided by an RNA primer

Question 16

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

Accepted Answer

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

Question 17

Which of the following statements about the difference between condensation and hydrolysis reactions is correct?

Accepted Answer

Condensation reactions join monomers to form polymers by removing water.

Question 18

A mutation prevents primase from functioning in a cell. What would be the most immediate effect on DNA replication?

Accepted Answer

No RNA primers would be synthesized, so DNA polymerase could not initiate DNA synthesis.

Question 19

Which of the following best explains why the sugar-phosphate backbone of DNA is hydrophilic?

Accepted Answer

The phosphate groups are negatively charged and interact with water.

Question 20

In eukaryotic chromosomes, why are there multiple origins of replication?

Accepted Answer

Multiple origins allow the large linear chromosomes to be replicated quickly and efficiently.

DNA Structure and Replication: Study Guide for General Biology

Study Guide - Practice Questions

Study Guide - Flashcards