Question 1

Which of the following is a structural difference between DNA and RNA?

Accepted Answer

DNA contains thymine while RNA contains uracil.

Question 2

What is the function of RNA in the process of gene expression?

Accepted Answer

RNA transmits genetic information and is involved in protein synthesis.

Question 3

Which of the following statements about RNA polymerases in eukaryotes is correct?

Accepted Answer

RNA polymerase II transcribes mRNA.

Question 4

A mutation in the promoter region of a gene most directly affects which aspect of gene expression?

Accepted Answer

The ability of RNA polymerase to bind and initiate transcription.

Question 5

Which of the following best describes the role of transcription factors in eukaryotic gene expression?

Accepted Answer

They bind to promoter elements and help recruit RNA polymerase.

Question 6

During mRNA processing in eukaryotes, which modification occurs at the 3' end of the mRNA?

Accepted Answer

Addition of a poly-A tail.

Question 7

Which equation correctly represents the polarity of a nucleic acid strand?

Accepted Answer

$$5' \rightarrow 3'$$

Question 8

What is the main difference between introns and exons?

Accepted Answer

Exons are expressed sequences that code for amino acids, introns are non-coding sequences.

Question 9

Which of the following is NOT a function of mRNA editing?

Accepted Answer

Introducing mutations into the DNA sequence.

Question 10

A researcher discovers a eukaryotic gene with multiple introns. What process must occur before the mRNA can be translated?

Accepted Answer

Splicing to remove introns and join exons.

Question 11

Which of the following is true about the selectivity of RNA polymerases in prokaryotes?

Accepted Answer

Selectivity is determined by sigma factors binding to promoter regions.

Question 12

Which of the following best explains why mRNA editing is not considered a mutation?

Accepted Answer

mRNA editing does not change the DNA sequence.

Question 13

Which of the following is a correct sequence of events in eukaryotic mRNA processing?

Accepted Answer

Transcription, addition of 5' cap, splicing, addition of poly-A tail

Question 14

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

Accepted Answer

The mRNA will be rapidly degraded and not translated.

Question 15

Which of the following is a feature of prokaryotic transcription that differs from eukaryotic transcription?

Accepted Answer

Prokaryotes use sigma factors to initiate transcription.

Question 16

Which of the following equations represents the number of nucleotides added to the poly-A tail of eukaryotic mRNA?

Accepted Answer

$$n = 50 	ext{ to } 250$$

Question 17

Which of the following is true about the location of RNA polymerase I in eukaryotic cells?

Accepted Answer

It is found in the nucleolus.

Question 18

A scientist is studying a gene with multiple exons and introns. Which process ensures that only the coding regions are present in the mature mRNA?

Accepted Answer

Splicing

Question 19

Which of the following is a direct result of mRNA editing?

Accepted Answer

Alteration of the protein sequence encoded by the mRNA

RNA Structure, Function, and Post-Transcriptional Processing

Study Guide - Practice Questions