Question 1

Which of the following best describes a structural difference between DNA and RNA?

Accepted Answer

DNA contains deoxyribose sugar, while RNA contains ribose sugar.

Question 2

During DNA replication in bacteria, which enzyme is responsible for synthesizing the new DNA strand by adding nucleotides to the growing chain?

Accepted Answer

DNA polymerase

Question 3

What is the primary function of helicase during DNA replication?

Accepted Answer

To unwind the DNA double helix

Question 4

In bacterial DNA replication, what is the role of primase?

Accepted Answer

It synthesizes short RNA primers needed to start DNA synthesis.

Question 5

Which molecule serves as the template during transcription?

Accepted Answer

DNA

Question 6

What is the main purpose of transcription in a cell?

Accepted Answer

To copy genetic information from DNA to RNA

Question 7

Which molecules are directly involved in the process of translation?

Accepted Answer

mRNA, tRNA, and ribosomes

Question 8

What is the primary purpose of translation in gene expression?

Accepted Answer

To synthesize proteins from mRNA

Question 9

Which of the following best describes an inducible operon?

Accepted Answer

It is usually off but can be turned on in the presence of a specific substrate.

Question 10

How can a point mutation affect a protein's function?

Accepted Answer

It may cause a single amino acid change, potentially altering protein function.

Question 11

Which of the following is an example of a mutagen and the type of mutation it typically causes?

Accepted Answer

Ultraviolet light, which causes thymine dimers

Question 12

Which type of plasmid is responsible for transferring antibiotic resistance genes between bacteria?

Accepted Answer

Resistance (R) plasmid

Question 13

Which of the following is NOT a type of genetic transfer in bacteria?

Accepted Answer

Replication

Question 14

A bacterial cell acquires a new trait after taking up naked DNA from its environment. What is this process called?

Accepted Answer

Transformation

Question 15

Which of the following equations correctly represents the central dogma of molecular biology?

Accepted Answer

$$DNA \rightarrow RNA \rightarrow Protein$$

Question 16

A frameshift mutation is most likely to result from which of the following?

Accepted Answer

An insertion or deletion of a nucleotide

Question 17

Which of the following best describes a repressible operon?

Accepted Answer

It is usually on but can be turned off when a corepressor is present.

Question 18

Which enzyme is responsible for joining Okazaki fragments during DNA replication?

Accepted Answer

Ligase

Question 19

Which of the following scenarios best illustrates horizontal gene transfer?

Accepted Answer

A bacterium acquires a plasmid carrying antibiotic resistance from another bacterium.

Question 20

Which of the following statements about gene expression control is correct?

Accepted Answer

Gene expression can be regulated at transcription, translation, and post-translation levels.

Microbiology Study Guide: Genetics, Gene Expression, and Mutation

Study Guide - Practice Questions