Question 1

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

Accepted Answer

DNA → RNA → Protein

Question 2

A mutation changes the DNA sequence from 5'-GAA-3' to 5'-GAG-3'. Both codons code for glutamic acid. What type of mutation is this?

Accepted Answer

Silent mutation

Question 3

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

Accepted Answer

RNA polymerase

Question 4

In eukaryotes, which RNA polymerase is responsible for transcribing mRNA?

Accepted Answer

RNA polymerase II

Question 5

What is the function of the 5' cap and 3' poly-A tail added to eukaryotic mRNA?

Accepted Answer

They help export mRNA from the nucleus, protect it from degradation, and assist in ribosome binding

Question 6

A bacterial gene is being transcribed and translated simultaneously. Which feature allows this to occur?

Accepted Answer

Lack of RNA processing

Question 7

Given the mRNA sequence 5'-AUGGCCUAA-3', use the codon table to determine the resulting amino acid sequence.

Accepted Answer

$$	ext{Met-Ala-Stop}$$

Question 8

Which of the following statements about the genetic code is correct?

Accepted Answer

The code is nearly universal among all organisms

Question 9

What is the role of aminoacyl-tRNA synthetase in translation?

Accepted Answer

It attaches the correct amino acid to its tRNA

Question 10

Which site on the ribosome does the incoming aminoacyl-tRNA first bind during elongation?

Accepted Answer

A site

Question 11

A mutation inserts two nucleotides into the coding region of a gene. What is the most likely result?

Accepted Answer

Frameshift mutation

Question 12

Which of the following best explains why some antibiotics can target bacterial ribosomes without harming eukaryotic cells?

Accepted Answer

Bacterial ribosomes have a different structure than eukaryotic ribosomes

Question 13

Which of the following is NOT a post-translational modification?

Accepted Answer

Addition of a 5' cap

Question 14

Alternative RNA splicing allows eukaryotic cells to:

Accepted Answer

Produce multiple proteins from a single gene

Question 15

Which of the following sequences is the correct order for the flow of genetic information in a eukaryotic cell?

Accepted Answer

DNA → pre-mRNA → mRNA → protein

Question 16

A tRNA has the anticodon 3'-UAC-5'. Which mRNA codon will it recognize, and which amino acid will it carry?

Accepted Answer

5'-AUG-3', Methionine

Question 17

Which of the following best describes a polyribosome (polysome)?

Accepted Answer

Multiple ribosomes translating a single mRNA simultaneously

Question 18

Which of the following mutations would most likely result in a nonfunctional protein?

Accepted Answer

A frameshift mutation near the start of the coding sequence

Question 19

What is the effect of a nonsense mutation?

Accepted Answer

It changes an amino acid codon to a stop codon, leading to premature termination

Question 20

Which of the following best explains the evolutionary significance of the nearly universal genetic code?

Accepted Answer

It allows genes from one organism to be expressed in another

Gene Expression: From Gene to Protein (Campbell Biology, Ch. 17) – Study Notes

Study Guide - Practice Questions