Question 1

Which enzyme is responsible for synthesizing RNA during the process of transcription?

Accepted Answer

RNA polymerase

Question 2

A mutation that changes a codon specifying an amino acid into a stop codon is called:

Accepted Answer

Nonsense mutation

Question 3

Which of the following best describes a frameshift mutation?

Accepted Answer

A mutation caused by insertion or deletion of nucleotides, altering the reading frame

Question 4

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

Accepted Answer

Helicase

Question 5

Which of the following is a consequence of a silent mutation?

Accepted Answer

The amino acid sequence remains unchanged

Question 6

A point mutation that results in a different amino acid being incorporated into a protein is called:

Accepted Answer

Missense mutation

Question 7

Which of the following best describes the role of the promoter in transcription?

Accepted Answer

It is the site where RNA polymerase binds to initiate transcription

Question 8

If a DNA sequence is 5'-ATGCGT-3', what would be the corresponding mRNA sequence after transcription?

Accepted Answer

5'-AUGCGU-3'

Question 9

Which of the following mutations is most likely to have a neutral effect on an organism's fitness?

Accepted Answer

Silent mutation

Question 10

What is the function of topoisomerase during DNA replication?

Accepted Answer

It relieves tension ahead of the replication fork

Question 11

A mutation in the beta-globin gene causes sickle-cell anemia. This is an example of which type of mutation?

Accepted Answer

Missense mutation

Question 12

Which of the following best describes a beneficial mutation?

Accepted Answer

A mutation that increases the fitness of an organism

Question 13

During translation, which molecule brings amino acids to the ribosome?

Accepted Answer

tRNA

Question 14

Which of the following is the correct sequence of events in gene expression?

Accepted Answer

Replication → Transcription → Translation

Question 15

If a single nucleotide insertion occurs in the coding region of a gene, what is the most likely result?

Accepted Answer

A frameshift mutation

Question 16

Which of the following codons is the start codon for translation in eukaryotes?

Accepted Answer

$$AUG$$

Question 17

A mutation changes the codon $$GAA ($$which codes for glutamic acid) to $$GAG ($$which also codes for glutamic acid). What type of mutation is this?

Accepted Answer

Silent mutation

Question 18

Which of the following best explains why most point mutations are neutral or deleterious rather than beneficial?

Accepted Answer

Most changes in DNA disrupt protein function or regulation

Question 19

Which of the following is NOT directly involved in the process of translation?

Accepted Answer

RNA polymerase

Question 20

A mutation that does not change the amino acid sequence of a protein is most likely to occur at which position in a codon?

Accepted Answer

Third position

DNA Replication, Transcription, Translation, and Mutations: Study Guide

Study Guide - Practice Questions