$$\text{DNA} \rightarrow \text{RNA} \rightarrow \text{Protein}$$

Question 1

Which statement best describes the 'one gene, one polypeptide hypothesis'?

Accepted Answer

Each gene codes for a single polypeptide, which may be a part of a protein.

Question 2

During transcription, which enzyme is responsible for synthesizing RNA from a DNA template?

Accepted Answer

RNA polymerase

Question 3

Where does translation occur in a eukaryotic cell?

Accepted Answer

Cytoplasm

Question 4

What is the 'Central Dogma of Molecular Biology'?

Accepted Answer

$$	ext{DNA} ightarrow 	ext{RNA} ightarrow 	ext{Protein}$$

Question 5

What is the significance of the redundancy of the genetic code?

Accepted Answer

Multiple codons can code for the same amino acid.

Question 6

Using the codon wheel, what amino acid does the codon $$	ext{AUG}$$ code for?

Accepted Answer

Methionine (Met)

Question 7

What is the function of the promoter in gene expression?

Accepted Answer

It is the site where RNA polymerase binds to initiate transcription.

Question 8

Which of the following best describes the difference between exons and introns?

Accepted Answer

Exons are expressed sequences that remain in mRNA, introns are removed.

Question 9

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

Accepted Answer

Nonsense mutation

Question 10

Why is gene regulation important in both prokaryotes and eukaryotes?

Accepted Answer

It allows cells to conserve energy and resources by producing proteins only when needed.

Question 11

What is the primary function of an operon in bacteria?

Accepted Answer

To regulate the simultaneous expression of multiple related genes.

Question 12

How does the lac operon respond when both glucose and lactose are present in the environment?

Accepted Answer

The lac operon is repressed due to the presence of glucose.

Question 13

What is the role of the TATA box in eukaryotic promoters?

Accepted Answer

It is a DNA sequence that helps position RNA polymerase for transcription initiation.

Question 14

What is the purpose of alternative splicing in eukaryotic cells?

Accepted Answer

To increase the diversity of proteins produced from a single gene.

Question 15

Which process is responsible for the removal of introns from pre-mRNA?

Accepted Answer

RNA splicing

Question 16

What is the function of ubiquitination in protein regulation?

Accepted Answer

It marks proteins for degradation by the proteasome.

Question 17

Which of the following best describes a mutagen?

Accepted Answer

A chemical or physical agent that causes mutations in DNA.

Question 18

What is the role of tRNA during translation?

Accepted Answer

It brings amino acids to the ribosome and matches them to the mRNA codon.

Question 19

Which part of the nucleosome can be methylated, and why is this important?

Accepted Answer

The DNA and histone tails; methylation can repress gene expression.

Question 20

A mutation changes the DNA sequence from $$	ext{TAC} to$$ $$	ext{TAG}. $$Using the codon wheel, what is the effect on the protein?

Accepted Answer

Methionine is replaced by a stop codon, terminating translation.

Gene Expression: From Gene to Protein & Regulation of Gene Expression (Chapters 14 & 15)

Study Guide - Practice Questions