Q: Which equation correctly represents the direction of DNA synthesis during replication?

$$\text{DNA polymerase synthesizes DNA in the 5' \rightarrow 3' direction}$$

Q: Which equation represents the Central Dogma of molecular biology?

$$\text{DNA} \rightarrow \text{RNA} \rightarrow \text{Protein}$$

Question 1

Which of the following best describes the role of the lac operon in prokaryotic gene regulation?

Accepted Answer

It enables bacteria to metabolize lactose only when lactose is present and glucose is absent.

Question 2

In the lac operon, what happens when lactose is present in the environment?

Accepted Answer

The repressor releases from the operator, allowing transcription to occur.

Question 3

Which equation correctly represents the direction of DNA synthesis during replication?

Accepted Answer

$$	ext{DNA polymerase synthesizes DNA in the 5' ightarrow 3' direction}$$

Question 4

Which of the following is a major difference between prokaryotic and eukaryotic gene regulation?

Accepted Answer

Eukaryotes regulate gene expression at multiple levels, including chromatin remodeling, while prokaryotes primarily regulate at the transcriptional level.

Question 5

What is the function of histone acetyltransferase (HAT) in eukaryotic cells?

Accepted Answer

HAT adds acetyl groups to histones, causing chromatin to decondense and increasing gene accessibility.

Question 6

A mutation in the lacI gene results in a nonfunctional repressor. What is the most likely outcome?

Accepted Answer

Transcription of the lac operon will occur continuously, regardless of lactose presence.

Question 7

Which of the following best explains why offspring of rats raised on a low-protein diet have abnormal histone modifications?

Accepted Answer

Patterns of gene expression may be inherited due to epigenetic changes.

Question 8

During DNA replication, which enzyme is responsible for relieving twisting forces ahead of the replication fork?

Accepted Answer

Topoisomerase

Question 9

Which of the following is a real-world example of alternative splicing?

Accepted Answer

The production of different forms of tropomyosin in skeletal and smooth muscle cells.

Question 10

Which equation represents the Central Dogma of molecular biology?

Accepted Answer

$$	ext{DNA} ightarrow 	ext{RNA} ightarrow 	ext{Protein}$$

Question 11

Which of the following is NOT a step in eukaryotic gene regulation?

Accepted Answer

Operator binding by repressor proteins

Question 12

What is the function of the A site in the ribosome during translation?

Accepted Answer

It is the acceptor site for incoming aminoacyl tRNA.

Question 13

Which of the following best describes the process of transcription initiation in bacteria?

Accepted Answer

Sigma factor helps RNA polymerase recognize and bind to the promoter region.

Question 14

Which enzyme is responsible for joining Okazaki fragments during lagging strand synthesis?

Accepted Answer

DNA ligase

Question 15

Which of the following is a consequence of histone deacetylase (HDAC) activity?

Accepted Answer

Chromatin becomes less accessible, decreasing gene expression.

Question 16

Which of the following is true about the structure of a nucleosome?

Accepted Answer

It consists of DNA wrapped around a group of 8 histone proteins.

Question 17

Which of the following is a real-world implication of epigenetic modifications?

Accepted Answer

A mother’s diet can influence gene expression patterns in her offspring throughout their life.

Question 18

Which of the following is required for transcription initiation in eukaryotes but not in prokaryotes?

Accepted Answer

Basal transcription factors

Question 19

Which equation best represents the relationship between mRNA stability and protein production?

Accepted Answer

$$	ext{Protein production} \propto 	ext{mRNA stability}$$

Study guide 24

Study Guide - Practice Questions

Study Guide - Flashcards