Question 1

Which of the following best describes the role of histone proteins in eukaryotic cells?

Accepted Answer

They package DNA into nucleosomes, allowing it to fit inside the nucleus.

Question 2

A prokaryotic cell contains a circular DNA molecule and plasmids. Which feature distinguishes its genome from that of a eukaryotic cell?

Accepted Answer

Presence of circular DNA and plasmids.

Question 3

During transcription, which strand of DNA serves as the template for RNA synthesis?

Accepted Answer

The anti-sense strand.

Question 4

Which sequence is commonly found in the -10 region of prokaryotic promoters and is essential for transcription initiation?

Accepted Answer

5'-TATAAT-3'

Question 5

What is the function of the sigma (σ) factor in prokaryotic transcription?

Accepted Answer

It recognizes and binds to promoter regions, enabling RNA polymerase to initiate transcription.

Question 6

Which of the following statements about eukaryotic transcription is TRUE?

Accepted Answer

Transcription occurs in the nucleus, and translation occurs in the cytoplasm.

Question 7

A segment of DNA is transcribed into RNA. The DNA template strand reads 3'-TACGGTACG-5'. What is the sequence of the resulting RNA?

Accepted Answer

$$5'	ext{AUGCCAUGC}\ 3'$$

Question 8

Which of the following is a major difference between prokaryotic and eukaryotic transcription?

Accepted Answer

Eukaryotes require transcription factors for initiation, while prokaryotes do not.

Question 9

Which post-transcriptional modification is unique to eukaryotic mRNA and increases its stability?

Accepted Answer

Addition of a poly(A) tail.

Question 10

In prokaryotic transcription, what is the consequence of a stem-loop (hairpin) structure forming in the RNA?

Accepted Answer

It causes the RNA polymerase to dissociate from the DNA, terminating transcription.

Question 11

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

Accepted Answer

DNA → RNA → Protein

Question 12

A eukaryotic gene contains both exons and introns. What happens to the introns during mRNA processing?

Accepted Answer

They are spliced out by the spliceosome.

Question 13

Which of the following is NOT a type of RNA produced during transcription?

Accepted Answer

DNA polymerase RNA

Question 14

In prokaryotes, which enzyme is responsible for synthesizing all types of RNA?

Accepted Answer

RNA polymerase

Question 15

Which of the following sequences is recognized by the TATA binding protein (TBP) in eukaryotic promoters?

Accepted Answer

5'-TATAAAA-3'

Question 16

A mutation in the promoter region of a gene could most likely affect which aspect of transcription?

Accepted Answer

The initiation of transcription.

Question 17

Which of the following statements about the directionality of transcription is correct?

Accepted Answer

RNA polymerase synthesizes RNA in the 5' to 3' direction.

Question 18

Which of the following is a consequence of the presence of introns in eukaryotic genes?

Accepted Answer

It allows a single gene to produce multiple protein variants through alternative splicing.

Question 19

Which step is unique to eukaryotic transcription compared to prokaryotic transcription?

Accepted Answer

RNA processing, including capping, polyadenylation, and splicing.

Transcription: From Genome Organization to RNA Synthesis in Prokaryotes and Eukaryotes

Study Guide - Practice Questions