Question 1

Which of the following statements best describes the difference between DNA and RNA molecules?

Accepted Answer

DNA contains deoxyribose sugar, while RNA contains ribose sugar.

Question 2

Which class of RNA is directly involved in carrying genetic information from DNA to the ribosome for protein synthesis?

Accepted Answer

mRNA

Question 3

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

Accepted Answer

5'-CGUACGCAU-3'

Question 4

Which of the following is a consensus sequence commonly found in eukaryotic promoters and is crucial for transcription initiation?

Accepted Answer

TATA box

Question 5

What is the primary function of the sigma subunit in bacterial RNA polymerase?

Accepted Answer

It enables RNA polymerase to recognize and bind to promoter sequences.

Question 6

Which of the following equations correctly represents the direction of RNA synthesis during transcription?

Accepted Answer

$$5' \rightarrow 3'$$

Question 7

A mutation occurs in the -10 region of a bacterial promoter. What is the most likely effect on transcription?

Accepted Answer

Transcription initiation may be impaired due to reduced promoter recognition.

Question 8

Which RNA polymerase is responsible for transcribing protein-coding genes in eukaryotes?

Accepted Answer

RNA polymerase II

Question 9

During eukaryotic mRNA processing, which modification is added to the 3' end of the transcript?

Accepted Answer

Poly-A tail

Question 10

Which of the following best explains the significance of alternative splicing in eukaryotic cells?

Accepted Answer

It allows a single gene to encode multiple protein variants.

Question 11

Which of the following is NOT a type of regulatory RNA?

Accepted Answer

mRNA

Question 12

A researcher discovers a mutation that prevents the addition of a 5' cap to eukaryotic mRNA. What is the most likely consequence?

Accepted Answer

The mRNA will be rapidly degraded and poorly translated.

Question 13

Which of the following statements about chromatin-based regulation is correct?

Accepted Answer

Chromatin compaction can restrict access of RNA polymerase II to DNA.

Question 14

Which of the following is a correct pairing of RNA nucleotide and its base?

Accepted Answer

Guanosine - Cytosine

Question 15

Which process occurs in eukaryotes but not in prokaryotes during mRNA maturation?

Accepted Answer

Addition of a 5' cap and poly-A tail

Question 16

A mutation in the CAAT box of a eukaryotic promoter would most likely affect which aspect of gene expression?

Accepted Answer

Initiation of transcription due to altered transcription factor binding

Question 17

Which of the following best describes the RNA world hypothesis?

Accepted Answer

RNA served as both genetic material and catalyst before DNA and proteins evolved.

Question 18

Which equation correctly represents the base pairing between DNA and RNA during transcription?

Accepted Answer

$$A_{DNA} \rightarrow U_{RNA}$$

Question 19

Which of the following is a direct result of a mutation in the termination region of a bacterial gene?

Accepted Answer

Transcription may continue past the normal endpoint, producing longer RNA.

Question 20

Which of the following steps is unique to eukaryotic post-transcriptional processing?

Accepted Answer

Splicing of introns from pre-mRNA

DNA, RNA, and Protein: Structure, Function, and Transcription

Study Guide - Practice Questions