Question 1

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

Accepted Answer

Genotype determines the possible features of a cell, while phenotype is the observable expression of those features.

Question 2

Which of the following statements about chromosomes is correct?

Accepted Answer

Eukaryotic cells have numerous linear chromosomes housed in the nucleus.

Question 3

Plasmids are important in microbiology because they:

Accepted Answer

Exist outside the chromosome and often confer survival advantages such as antibiotic resistance.

Question 4

Which of the following nitrogen bases is found only in RNA?

Accepted Answer

Uracil (U)

Question 5

What is the directionality of DNA synthesis during replication?

Accepted Answer

$$5' \rightarrow 3'$$

Question 6

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

Accepted Answer

Helicase

Question 7

Which of the following best describes the semiconservative nature of DNA replication?

Accepted Answer

Each new DNA molecule contains one original parent strand and one newly synthesized strand.

Question 8

In the process of transcription, which enzyme synthesizes RNA from a DNA template?

Accepted Answer

RNA polymerase

Question 9

Which type of RNA contains an anticodon loop and carries amino acids to the ribosome?

Accepted Answer

Transfer RNA (tRNA)

Question 10

A frameshift mutation is most likely to occur when:

Accepted Answer

One or more nucleotides are inserted or deleted, not in multiples of three.

Question 11

Which mechanism of horizontal gene transfer involves the transfer of DNA through a bacteriophage?

Accepted Answer

Transduction

Question 12

Which of the following is NOT a method of horizontal gene transfer?

Accepted Answer

Binary fission

Question 13

Which enzyme is responsible for sealing nicks in the DNA sugar-phosphate backbone during replication and repair?

Accepted Answer

Ligase

Question 14

A missense mutation results in:

Accepted Answer

A codon being changed so that a different amino acid is incorporated.

Question 15

Which of the following best explains why the genetic code is considered redundant?

Accepted Answer

Multiple codons can code for the same amino acid.

Question 16

Which of the following is a real-world example of horizontal gene transfer that can lead to antibiotic resistance?

Accepted Answer

Transfer of a plasmid carrying resistance genes via conjugation

Question 17

During translation, what is the role of the ribosome?

Accepted Answer

Assembles proteins by reading mRNA and facilitating peptide bond formation between amino acids

Question 18

Which of the following best describes the function of excision repair enzymes?

Accepted Answer

They cut out damaged or mismatched DNA, allowing DNA polymerase and ligase to repair the strand.

Question 19

Which of the following is a biological mutagen that can introduce new genetic combinations?

Accepted Answer

Transposons

Question 20

A scientist observes a bacterial cell that has acquired a new gene for toxin production after exposure to a virus. Which process most likely occurred?

Accepted Answer

Transduction

Microbiology Chapter 5: Genetics – Structured Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards