$E = \frac{RT}{zF} \ln \left( \frac{[\text{ion}]_{\text{outside}}}{[\text{ion}]_{\text{inside}}} \right)$

Question 1

Which of the following best describes the role of the ribosome during mRNA translation?

Accepted Answer

It catalyzes the formation of peptide bonds between amino acids.

Question 2

A mutation changes a codon from UAU (tyrosine) to UAA. What type of mutation is this?

Accepted Answer

Nonsense mutation

Question 3

Which of the following is a trans-acting element in gene regulation?

Accepted Answer

Transcription factor protein

Question 4

In the lac operon model, what is the effect of lactose on the repressor protein?

Accepted Answer

Lactose binds to the repressor, causing it to release from the operator.

Question 5

Which checkpoint in the cell cycle ensures that DNA is undamaged before mitosis begins?

Accepted Answer

G2-M checkpoint

Question 6

A scientist wants to amplify a specific DNA sequence from a small sample. Which method should they use?

Accepted Answer

PCR (Polymerase Chain Reaction)

Question 7

During G protein-coupled receptor (GPCR) signaling, what is the role of GTP?

Accepted Answer

GTP binding activates the G protein, allowing it to transmit the signal.

Question 8

Which of the following best explains why CRISPR-Cas9 is preferred over PCR for gene editing?

Accepted Answer

CRISPR-Cas9 can directly modify DNA sequences, while PCR only amplifies DNA.

Question 9

Which of the following codons is a start codon in eukaryotic mRNA translation?

Accepted Answer

AUG

Question 10

A patient is infected with SARS-CoV-2. Which cellular receptor does the virus use to enter human cells?

Accepted Answer

ACE2 receptor

Question 11

Which of the following best describes a silent mutation?

Accepted Answer

A mutation that does not change the amino acid sequence due to redundancy in the genetic code.

Question 12

Which method would you use to measure the level of mRNA expression of a specific gene?

Accepted Answer

Transcriptionomics

Question 13

Which of the following is a cis-acting element in gene regulation?

Accepted Answer

Enhancer sequence

Question 14

During the cell cycle, which cyclin is required to initiate DNA replication at the restriction point?

Accepted Answer

Cyclin E

Question 15

Which of the following best describes the ethical concern associated with CRISPR gene editing in embryos?

Accepted Answer

Potential for off-target mutations and heritable genetic changes.

Question 16

Which step in nerve impulse transmission involves the rapid influx of Na$^+$ ions?

Accepted Answer

Depolarization

Question 17

Which of the following equations correctly represents the calculation of membrane potential using the Nernst equation?

Accepted Answer

$E = \frac{RT}{zF} \ln \left( \frac{[	ext{ion}]_{	ext{outside}}}{[	ext{ion}]_{	ext{inside}}} ight)$

Question 18

Which of the following best explains the concept of signal amplification in G protein-coupled receptor pathways?

Accepted Answer

One ligand binding event can activate many downstream molecules, increasing the cellular response.

Question 19

A scientist wants to separate DNA fragments by size. Which method should they use?

Accepted Answer

Gel electrophoresis

Question 20

Which of the following is a real-world example of post-translational modification?

Accepted Answer

Addition of a phosphate group to a protein after translation

Comprehensive Study Notes for Cell Biology Exam Topics

Study Guide - Practice Questions