$\text{Number of divisions} \propto \text{Initial telomere length}$

Question 1

Which experiment demonstrated that DNA, and not protein, is the genetic material responsible for bacterial transformation?

Accepted Answer

Avery, MacLeod, and McCarty's experiment using DNase, RNase, and protease

Question 2

In Griffith's experiment, what was the result when mice were injected with a mixture of heat-killed type S bacteria and live type R bacteria?

Accepted Answer

The mice died and live type S bacteria were found in their blood.

Question 3

Which of the following is a purine found in DNA?

Accepted Answer

Adenine

Question 4

What is the chemical difference between the sugars in DNA and RNA?

Accepted Answer

DNA contains deoxyribose, while RNA contains ribose.

Question 5

Which equation correctly represents Chargaff's rule for base pairing in DNA?

Accepted Answer

$A = T$ and $G = C$

Question 6

What is the directionality of a DNA strand, and which group is exposed at the 3' end?

Accepted Answer

DNA is written 5' to 3', with a hydroxyl group exposed at the 3' end.

Question 7

Which feature of DNA allows proteins to bind and regulate gene expression?

Accepted Answer

Major groove

Question 8

The Meselson-Stahl experiment used isotopes of nitrogen to demonstrate which model of DNA replication?

Accepted Answer

Semiconservative replication

Question 9

Which enzyme is responsible for synthesizing the RNA primer during DNA replication?

Accepted Answer

DNA primase

Question 10

Why is DNA polymerization considered exergonic?

Accepted Answer

Because the formation of phosphodiester bonds releases energy from the hydrolysis of dNTPs.

Question 11

What is the main difference between the synthesis of the leading and lagging strands during DNA replication?

Accepted Answer

The leading strand is synthesized continuously, while the lagging strand is synthesized in Okazaki fragments.

Question 12

Which enzyme joins adjacent DNA fragments on the lagging strand?

Accepted Answer

DNA ligase

Question 13

What is the function of telomerase in eukaryotic cells?

Accepted Answer

It adds repetitive DNA sequences to the ends of chromosomes to prevent shortening.

Question 14

Which equation best represents the relationship between the number of cell divisions and telomere length in somatic cells?

Accepted Answer

$	ext{Number of divisions} \propto 	ext{Initial telomere length}$

Question 15

Which of the following best describes the structure of a nucleosome?

Accepted Answer

A nucleosome consists of DNA wrapped around eight histone proteins.

Question 16

What is the effect of DNA compaction into heterochromatin during cell division?

Accepted Answer

It makes chromosomes highly compacted and less accessible for transcription.

Question 17

Which DNA polymerase in E. coli is primarily responsible for the majority of DNA replication?

Accepted Answer

DNA polymerase III

Question 18

Which of the following mechanisms ensures the high fidelity of DNA replication?

Accepted Answer

Proofreading activity of DNA polymerase

Question 19

Which equation represents the formation of a phosphodiester bond during DNA synthesis?

Accepted Answer

$	ext{DNA}_{n} + 	ext{dNTP} ightarrow 	ext{DNA}_{n+1} + 	ext{PP}_{i}$

Question 20

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

Accepted Answer

Eukaryotic chromosomes are linear and very large, so multiple origins speed up replication.

Chapter 11 Study Guide

Study Guide - Practice Questions