Question 1

Which of the following best describes the relationship between genotype and phenotype in a bacterial cell?

Accepted Answer

Genotype is the genetic makeup that determines the phenotype, which is the observable traits.

Question 2

Which of the following statements about prokaryotic and eukaryotic genomes is CORRECT?

Accepted Answer

Prokaryotic genomes are typically circular and may include plasmids, while eukaryotic genomes are linear and found in the nucleus.

Question 3

Which of the following is a function of plasmids in bacteria?

Accepted Answer

They often carry genes that confer a survival advantage, such as antibiotic resistance.

Question 4

Which enzyme is responsible for unwinding the DNA double helix during DNA replication?

Accepted Answer

Helicase

Question 5

During DNA replication, which enzyme synthesizes short RNA primers to initiate replication?

Accepted Answer

Primase

Question 6

Which of the following best explains why Okazaki fragments are formed during DNA replication?

Accepted Answer

The lagging strand is synthesized discontinuously in short segments because DNA polymerase can only add nucleotides in the 5' to 3' direction.

Question 7

Which of the following is a correct description of the central dogma of molecular biology?

Accepted Answer

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

Question 8

Which of the following is TRUE regarding the structure of DNA?

Accepted Answer

DNA is a double-stranded helix with antiparallel strands and thymine as one of its bases.

Question 9

Which of the following best describes a missense mutation?

Accepted Answer

A mutation that results in a different amino acid being incorporated into the protein.

Question 10

A bacterial cell acquires a gene for antibiotic resistance from its environment, without cell-to-cell contact. Which process is responsible?

Accepted Answer

Transformation

Question 11

Which of the following statements about transcription in eukaryotes is CORRECT?

Accepted Answer

Transcription occurs in the nucleus and mRNA must be spliced before translation.

Question 12

Which of the following is a function of tRNA during translation?

Accepted Answer

It brings specific amino acids to the ribosome based on the mRNA codon sequence.

Question 13

Which of the following best describes a frameshift mutation?

Accepted Answer

A mutation that results in the insertion or deletion of nucleotides not in multiples of three, altering the reading frame.

Question 14

Which of the following is a key difference between prokaryotic and eukaryotic DNA replication?

Accepted Answer

Eukaryotic DNA replication involves multiple origins of replication, while prokaryotic DNA replication typically has a single origin.

Question 15

Which of the following is an example of horizontal gene transfer in bacteria?

Accepted Answer

A bacterium acquiring a gene from a bacteriophage through transduction.

Question 16

Which of the following best explains why antibiotics that target bacterial ribosomes do not usually harm human cells?

Accepted Answer

Bacterial ribosomes are structurally different from eukaryotic ribosomes, allowing selective targeting.

Question 17

Which of the following is TRUE about the directionality of nucleic acids?

Accepted Answer

DNA and RNA are both synthesized in the 5' to 3' direction.

Question 18

A mutation changes a DNA codon from AAA to AAG, but both code for lysine. What type of mutation is this?

Accepted Answer

Silent mutation

Question 19

Which of the following is a role of ligase during DNA replication?

Accepted Answer

Seals nicks in the sugar-phosphate backbone, joining Okazaki fragments.

Question 20

Which of the following best describes the function of rRNA?

Accepted Answer

It forms the core structure of the ribosome and catalyzes peptide bond formation.

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

Study Guide - Practice Questions