Question 1

Which of the following best describes the central dogma of molecular biology?

Accepted Answer

DNA is transcribed into RNA, which is then translated into protein.

Question 2

In bacterial cells, which structure contains the majority of genetic information?

Accepted Answer

Circular chromosomes

Question 3

During DNA replication, which enzyme is responsible for unwinding the DNA double helix?

Accepted Answer

Helicase

Question 4

What is the role of Okazaki fragments in DNA replication?

Accepted Answer

They are short DNA fragments synthesized on the lagging strand.

Question 5

Which of the following base pairs is held together by three hydrogen bonds?

Accepted Answer

Cytosine-Guanine

Question 6

A mutation that results in the insertion or deletion of nucleotides, shifting the reading frame, is called:

Accepted Answer

Frameshift mutation

Question 7

Which process describes the transfer of genes from one bacterium to another via 'naked' DNA?

Accepted Answer

Transformation

Question 8

What is the function of tRNA during translation?

Accepted Answer

It carries amino acids to the ribosome and matches them to the mRNA codon.

Question 9

Which codon serves as the start signal for translation in most organisms?

Accepted Answer

AUG

Question 10

Which of the following statements about plasmids is TRUE?

Accepted Answer

Plasmids often carry genes that enhance bacterial pathogenicity.

Question 11

During bacterial conjugation, what is required for the transfer of plasmids?

Accepted Answer

Cell-to-cell contact via sex pili

Question 12

Which type of mutation results in a premature stop codon?

Accepted Answer

Nonsense mutation

Question 13

What is the difference between vertical and horizontal gene transfer?

Accepted Answer

Vertical transfer occurs from parent to offspring; horizontal transfer occurs between cells of the same generation.

Question 14

Which enzyme is responsible for synthesizing RNA from a DNA template during transcription?

Accepted Answer

RNA polymerase

Question 15

If a DNA sequence is 5'-ATGCGT-3', what would be the complementary RNA sequence produced during transcription?

Accepted Answer

5'-UACGCA-3'

Question 16

Which of the following is a consequence of a frameshift mutation in a coding region?

Accepted Answer

The reading frame of the mRNA is altered, potentially changing every amino acid downstream.

Question 17

Which process involves the transfer of bacterial DNA via a bacteriophage?

Accepted Answer

Transduction

Question 18

What is the main reason DNA replication in bacteria is highly accurate?

Accepted Answer

The proofreading capability of DNA polymerase

Question 19

Which of the following best explains why genetic diversity is important for evolution?

Accepted Answer

It allows organisms to survive in a variety of environments through natural selection.

Question 20

A bacterial cell is exposed to a mutagen that causes a base substitution in a gene. What is the most likely outcome?

Accepted Answer

The protein encoded by the gene may have a single amino acid change.

Microbial Genetics: Structure, Function, and Variability of Genetic Material

Study Guide - Practice Questions