Question 1

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

Accepted Answer

DNA is transcribed into RNA, which is then translated into protein.

Question 2

During transcription in eukaryotic cells, which of the following modifications occurs to the pre-mRNA before it exits the nucleus?

Accepted Answer

Addition of a 5' cap and a 3' poly-A tail

Question 3

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

Accepted Answer

RNA polymerase

Question 4

A mutation occurs in the TATA box of a eukaryotic gene. What is the most likely consequence?

Accepted Answer

Transcription factors may not bind properly, reducing transcription initiation.

Question 5

Which of the following statements about introns and exons is correct?

Accepted Answer

Introns are non-coding regions that are removed, while exons are spliced together to form mature mRNA.

Question 6

Alternative splicing allows a single gene to:

Accepted Answer

Code for multiple proteins by including or excluding different exons.

Question 7

Which type of RNA carries amino acids to the ribosome during translation?

Accepted Answer

tRNA

Question 8

What is the function of the ribosome during translation?

Accepted Answer

It facilitates the matching of tRNA anticodons with mRNA codons and forms peptide bonds between amino acids.

Question 9

Given the DNA template strand 3'-TACGGTACG-5', what is the corresponding mRNA sequence produced during transcription?

Accepted Answer

5'-AUGCCAUGC-3'

Question 10

A patient has a mutation that prevents the addition of a 5' cap to mRNA. What is a likely consequence?

Accepted Answer

The mRNA will not be exported from the nucleus and will be rapidly degraded.

Question 11

Which codon serves as the start codon for translation in eukaryotes, and which amino acid does it code for?

Accepted Answer

AUG; methionine

Question 12

During translation, what happens when a stop codon is reached?

Accepted Answer

A release factor binds, causing the polypeptide to be released from the ribosome.

Question 13

Which of the following best explains why uracil is found in RNA but not in DNA?

Accepted Answer

Uracil is less stable than thymine and is only suitable for short-lived molecules like RNA.

Question 14

A scientist wants to design an experiment to block translation in a cell. Which of the following would be the most effective target?

Accepted Answer

Inhibit the function of ribosomal RNA (rRNA).

Question 15

Which of the following is a correct pairing between a codon and its corresponding anticodon?

Accepted Answer

Codon: 5'-AUG-3'; Anticodon: 3'-UAC-5'

Question 16

Which of the following best describes the role of spliceosomes in eukaryotic cells?

Accepted Answer

They remove introns and join exons in pre-mRNA.

Question 17

If a mutation causes a premature stop codon in the middle of an mRNA sequence, what is the most likely result?

Accepted Answer

A truncated, likely nonfunctional protein will be produced.

Question 18

Which of the following is NOT a function of the 5' cap and 3' poly-A tail added to eukaryotic mRNA?

Accepted Answer

Coding for amino acids in the final protein

Question 19

A researcher observes that a single gene can produce multiple protein isoforms in a cell. Which process best explains this observation?

Accepted Answer

Alternative splicing

Protein Synthesis: Transcription and Translation Study Guide

Study Guide - Practice Questions