Question 1

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

Accepted Answer

Hershey and Chase's experiment using radioactive isotopes to label viral DNA and protein

Question 2

In the Hershey-Chase experiment, why was $$^{32}P$$ used to label DNA and $$^{35}S$$ used to label protein?

Accepted Answer

$$^{32}P is $$found in DNA but not in protein, and $$^{35}S is $$found in protein but not in DNA

Question 3

According to Chargaff’s rules, if a DNA molecule contains 30% adenine, what percentage of guanine would you expect?

Accepted Answer

20%

Question 4

Which of the following best describes the structure of a DNA nucleotide?

Accepted Answer

A phosphate group, a deoxyribose sugar, and a nitrogenous base

Question 5

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

Accepted Answer

Helicase

Question 6

During DNA replication, why is one strand synthesized continuously while the other is synthesized in fragments?

Accepted Answer

DNA polymerase can only add nucleotides to the 3' end, so the lagging strand is synthesized in Okazaki fragments

Question 7

What is the function of DNA ligase during DNA replication?

Accepted Answer

It joins Okazaki fragments by sealing the sugar-phosphate backbone

Question 8

A mutation occurs that disables the proofreading function of DNA polymerase. What is the most likely consequence?

Accepted Answer

The accuracy of DNA replication will decrease, leading to more mutations

Question 9

Which of the following best explains why telomeres are important for eukaryotic chromosomes?

Accepted Answer

They prevent the loss of essential genes during DNA replication

Question 10

Which of the following statements about nucleosomes is correct?

Accepted Answer

Nucleosomes are made of DNA wrapped around histone proteins

Question 11

A scientist isolates a DNA sample and finds that 18% of the bases are cytosine. According to Chargaff’s rules, what percentage of the bases are adenine?

Accepted Answer

32%

Question 12

Which enzyme is responsible for synthesizing short RNA primers during DNA replication?

Accepted Answer

Primase

Question 13

What is the role of topoisomerase during DNA replication?

Accepted Answer

It breaks, swivels, and rejoins DNA strands to relieve tension ahead of the replication fork

Question 14

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

Accepted Answer

5' to 3' direction

Question 15

A patient is diagnosed with a genetic disorder caused by a failure to repair thymine dimers in DNA. Which enzyme is most likely defective?

Accepted Answer

Nuclease

Question 16

Which of the following is a correct statement about the antiparallel nature of DNA?

Accepted Answer

One strand runs 5' to 3' and the other runs 3' to 5'

Question 17

Which of the following is a real-life consequence of telomere shortening in human cells?

Accepted Answer

Cell division eventually stops as telomeres become too short

Question 18

Which of the following best explains why prokaryotic DNA does not form nucleosomes?

Accepted Answer

Prokaryotes lack histone proteins

Question 19

A mutation in the gene encoding single-strand binding proteins would most likely result in which of the following during DNA replication?

Accepted Answer

The separated DNA strands would re-anneal before replication is complete

Question 20

Which of the following best describes the semiconservative model of DNA replication?

Accepted Answer

Each new DNA molecule consists of one old strand and one new strand

Chapter 16 Study Guide

Study Guide - Practice Questions

Study Guide - Flashcards