Question 1

Which of the following best describes the flow of genetic information according to the central dogma of molecular biology?

Accepted Answer

$$DNA \rightarrow RNA \rightarrow Protein$$

Question 2

Which structural feature is unique to RNA compared to DNA?

Accepted Answer

RNA contains the sugar ribose, while DNA contains deoxyribose.

Question 3

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

Accepted Answer

DNA gyrase

Question 4

Which of the following statements correctly compares the leading and lagging strands during DNA replication?

Accepted Answer

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

Question 5

In prokaryotic transcription, what is the primary role of RNA polymerase?

Accepted Answer

To synthesize RNA from a DNA template

Question 6

Which of the following best describes the difference between codons and anticodons?

Accepted Answer

Codons are sequences of three nucleotides on mRNA, while anticodons are complementary sequences on tRNA.

Question 7

A DNA sequence is 5'-ATG GAA TGA-3'. Using a codon table, which amino acids are encoded by the corresponding mRNA?

Accepted Answer

Methionine, Glutamic acid, Stop

Question 8

Which of the following statements about operons is correct?

Accepted Answer

Inducible operons are usually off but can be turned on in response to a substrate.

Question 9

Which microbe uses reverse transcription, and what is the process?

Accepted Answer

HIV uses reverse transcription to synthesize DNA from an RNA template.

Question 10

Which type of mutation is most likely to result in a nonfunctional protein?

Accepted Answer

Frameshift mutation

Question 11

What is the main purpose of the Ames test?

Accepted Answer

To assess the mutagenic potential of chemical compounds

Question 12

Which process allows bacteria to acquire new genetic material from their environment, as demonstrated by Griffith’s experiments with S. pneumoniae?

Accepted Answer

Transformation

Question 13

Which of the following best explains why RNA viruses evolve faster than DNA viruses?

Accepted Answer

RNA-dependent RNA polymerases lack proofreading activity, leading to higher mutation rates.

Question 14

Which of the following is NOT a criterion used to classify viruses?

Accepted Answer

Type of cell wall

Question 15

What is the difference between antigenic drift and antigenic shift in influenza viruses?

Accepted Answer

Antigenic drift involves gradual mutations, while antigenic shift involves reassortment of genome segments.

Question 16

Which of the following best describes the lytic cycle of a bacteriophage?

Accepted Answer

The phage replicates and lyses the host cell to release new virions.

Question 17

Which of the following is a common method for culturing animal viruses in the laboratory?

Accepted Answer

Inoculation of viruses into embryonated chicken eggs

Question 18

Which of the following is an example of an oncogenic virus and the cancer it may cause?

Accepted Answer

Human papillomavirus (HPV) and cervical cancer

Question 19

Which of the following best describes a prion?

Accepted Answer

An infectious protein that can cause neurodegenerative diseases such as Creutzfeldt-Jakob disease

Question 20

Which of the following best explains the basis for the Gram stain differentiating bacteria?

Accepted Answer

Differences in the thickness of the peptidoglycan layer in the cell wall

Microbiology Module 2 Study Guide – Step-by-Step Guidance

Study Guide - Practice Questions