Question 1

Which of the following statements best describes the central dogma of molecular genetics?

Accepted Answer

Genetic information flows from DNA to RNA to protein.

Question 2

A bacterial gene has two overlapping open reading frames (ORFs). What is a likely consequence of this arrangement?

Accepted Answer

Multiple proteins can be produced from a single mRNA transcript.

Question 3

Which of the following is NOT a difference between DNA and RNA?

Accepted Answer

RNA contains thymine, while DNA contains uracil.

Question 4

What is the role of the sigma ($$ \sigma ) $$subunit in bacterial RNA polymerase?

Accepted Answer

It binds to the promoter region to initiate transcription.

Question 5

Given the template DNA strand 3'-CTTTTTTGCCAT-5', what is the sequence of the mRNA produced?

Accepted Answer

$$5'-GAAAAAACGGUA-3'$$

Question 6

Which of the following best describes the process of chain elongation during bacterial transcription?

Accepted Answer

RNA polymerase adds nucleotides to the 3' end of the growing RNA strand.

Question 7

Which of the following is a function of the 5' cap added to eukaryotic mRNA?

Accepted Answer

It protects the mRNA from degradation and assists in translation initiation.

Question 8

Which enzyme is responsible for synthesizing mRNA in eukaryotes?

Accepted Answer

RNA polymerase II

Question 9

What is the main difference between transcription in prokaryotes and eukaryotes?

Accepted Answer

Eukaryotic transcription requires chromatin remodeling and mRNA processing.

Question 10

Which of the following sequences is recognized by the sigma subunit in E. coli promoters?

Accepted Answer

TATAAT and TTGACA

Question 11

A mutation prevents the removal of the sigma factor from RNA polymerase in bacteria. What is the most likely result?

Accepted Answer

Transcription elongation will be impaired.

Question 12

Which of the following best describes an intron?

Accepted Answer

A non-coding sequence removed from pre-mRNA during splicing.

Question 13

What is the function of the spliceosome in eukaryotic cells?

Accepted Answer

It removes introns from pre-mRNA and joins exons.

Question 14

Which of the following is a real-world application of understanding transcription termination in bacteria?

Accepted Answer

Designing antibiotics that inhibit bacterial RNA polymerase.

Question 15

Which of the following best explains why mature eukaryotic mRNA is smaller than the initial pre-mRNA transcript?

Accepted Answer

Introns are removed during splicing.

Question 16

A researcher observes that a eukaryotic gene is not expressed unless chromatin is decondensed. What process is most directly involved?

Accepted Answer

Chromatin remodeling

Question 17

Which of the following is true about the coding strand of DNA?

Accepted Answer

Its sequence is identical to the mRNA except T replaces U.

Question 18

Which of the following is a key reason why introns are important in eukaryotic genes?

Accepted Answer

They allow for alternative splicing and gene regulation.

Question 19

Which of the following best describes the role of snRNAs in the spliceosome?

Accepted Answer

They provide catalytic activity for splicing reactions.

Question 20

A mutation in the TATA box of a eukaryotic gene would most likely affect which process?

Accepted Answer

Initiation of transcription

Chapter 13: The Genetic Code and Transcription – Mini-Textbook Study Notes

Study Guide - Practice Questions