Microbial Genetics and Evolution Quizzes for Medical Microbiology Students

Question 1

Which of the following is NOT a mechanism of genetic recombination in bacteria?

Accepted Answer

Site-specific recombination

Answer

Transformation

Answer

Transduction

Answer

Conjugation

Question 2

Which of the following is NOT a mechanism of genetic variation in bacteria?

Accepted Answer

Deletion

Answer

Transformation

Answer

Transduction

Answer

Conjugation

Question 3

Silencers play a crucial role in gene regulation. Which of the following accurately describes their function?

Accepted Answer

Silencers are DNA sequences that bind repressor proteins, preventing transcription initiation.

Answer

Silencers are RNA molecules that bind to the promoter region, blocking transcription factors from binding.

Answer

Silencers are proteins that bind to enhancers, enhancing the rate of transcription.

Question 4

Which DNA polymerase is involved in DNA replication in prokaryotes?

Accepted Answer

Pol III

Answer

Pol I

Answer

Pol II

Answer

Pol IV

Question 5

What is the complementary DNA sequence to the following strand: 5'-ATGCGTA-3'?

Accepted Answer

5'-TACGCAT-3'

Answer

5'-ATGCGTA-3'

Answer

5'-UACGCUA-3'

Answer

5'-GTACGTA-3'

Question 6

Which of the following is a mechanism of gene regulation in bacteria?

Accepted Answer

Transcriptional attenuation

Answer

Translational elongation

Answer

Protein phosphorylation

Answer

Hormonal signaling

Question 7

Describe the difference between a missense and a nonsense mutation.

Accepted Answer

Missense mutations change the amino acid sequence, while nonsense mutations introduce a stop codon.

Answer

Nonsense mutations change the amino acid sequence, while missense mutations introduce a stop codon.

Answer

Missense mutations occur in coding regions, while nonsense mutations occur in non-coding regions.

Answer

Nonsense mutations occur in coding regions, while missense mutations occur in non-coding regions.

Question 8

Explain the role of horizontal gene transfer in microbial evolution.

Accepted Answer

It allows the rapid acquisition of new genes.

Answer

It ensures the faithful inheritance of genes from parent to offspring.

Answer

It prevents the accumulation of harmful mutations.

Answer

It promotes genetic diversity within a population.

Question 9

What is the significance of the endosymbiotic theory in the evolution of eukaryotes?

Accepted Answer

It explains the origin of eukaryotic cells.

Answer

It provides evidence for the role of horizontal gene transfer in evolution.

Answer

It demonstrates the importance of genetic drift in microbial populations.

Answer

It supports the idea that all life originated from a single common ancestor.

Question 10

Which enzyme unwinds the DNA double helix, allowing for DNA replication?

Accepted Answer

Helicase

Answer

DNA polymerase

Answer

Ligase

Question 11

Which nitrogenous base is NOT found in DNA?

Accepted Answer

Uridine

Answer

Adenine

Answer

Thymine

Answer

Cytosine

Question 12

What process translates the nucleotide sequence of an RNA molecule into the amino acid sequence of a protein?

Accepted Answer

Translation

Answer

Transcription

Answer

Replication

Answer

Reverse transcription

Question 13

What process enables a microorganism to acquire genetic material from another microorganism?

Accepted Answer

Horizontal gene transfer

Answer

Vertical gene transfer

Answer

Transduction

Answer

Conjugation

Question 14

Which type of mutation involves the insertion of a nucleotide into a DNA sequence?

Accepted Answer

Insertion

Answer

Substitution

Answer

Deletion

Answer

Inversion

Question 15

What process allows a virus to incorporate host DNA into its genome?

Accepted Answer

Retroviral transduction

Answer

Horizontal gene transfer

Answer

Encapsidation

Answer

Lysis

Question 16

Which component is NOT found in DNA structure?

Accepted Answer

Uracil

Answer

Deoxyribose

Answer

Phosphate

Answer

Adenine

Question 17

The process by which DNA creates an identical copy of itself during cell division is called:

Accepted Answer

Replication

Answer

Transcription

Answer

Mutation

Answer

Translation

Question 18

What is the term for a change in the DNA sequence?

Accepted Answer

Mutation

Answer

Recombination

Answer

Evolution

Answer

Gene expression

Question 19

What are the key applications of microbial genetics in biotechnology?

Accepted Answer

Genetic engineering, antibiotic production, and vaccine development

Answer

Microbial fuel cells and environmental cleanup

Answer

Forensic analysis and astrobiology

Question 20

What is the process called where a DNA molecule is duplicated to create two identical copies?

Accepted Answer

DNA replication

Answer

Translation

Answer

Transcription

Answer

Mutation

Question 21

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

Accepted Answer

Helicase

Answer

Polymerase

Answer

Exonuclease

Answer

Ligase

Question 22

Which of the following describes a process where genetic material is exchanged between organisms?

Accepted Answer

Genetic recombination

Answer

Transcription

Answer

Mutation

Answer

Replication

Question 23

What is the process called when a virus carries genetic material from one bacterium to another?

Accepted Answer

Transduction

Answer

Transformation

Answer

Transposition

Answer

Conjugation

Question 24

Which of these describes a mechanism where genetic material is transferred between organisms that are not parent and offspring?

Accepted Answer

Horizontal gene transfer

Answer

Transcription

Answer

DNA replication

Answer

Protein synthesis

Question 25

Bacteria that possess a gene that makes them resistant to a specific antibiotic are known as:

Accepted Answer

Antibiotic-resistant

Answer

Antibiotic-sensitive

Answer

Antibiotic-dependent

Answer

Antibiotic-tolerant

Question 26

What is the term for a permanent alteration in the genetic material of a bacterium?

Accepted Answer

Mutation

Answer

Transformation

Answer

Recombination

Answer

Transposition

Question 27

Which type of mutation involves a change in the order of nucleotides within a gene?

Accepted Answer

Inversion

Answer

Deletion

Answer

Insertion

Answer

Substitution