$$\text{DNA} \rightarrow \text{RNA} \rightarrow \text{Protein}$$

Question 1

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

Accepted Answer

$$	ext{DNA} ightarrow 	ext{RNA} ightarrow 	ext{Protein}$$

Question 2

In bacteria, what is the role of the sigma protein during transcription initiation?

Accepted Answer

It recognizes and binds to the promoter region, guiding RNA polymerase to the correct start site.

Question 3

Which DNA strand has the same sequence as the RNA transcript (except for T/U substitution)?

Accepted Answer

Non-template (coding) strand

Question 4

What is the function of the -10 and -35 boxes in bacterial promoters?

Accepted Answer

They are binding sites for sigma proteins, helping RNA polymerase recognize the promoter.

Question 5

Which of the following is a key difference between transcription in bacteria and eukaryotes?

Accepted Answer

Eukaryotic transcription occurs in the nucleus, while bacterial transcription occurs in the cytoplasm.

Question 6

During RNA processing in eukaryotes, what is the function of the spliceosome?

Accepted Answer

It removes introns and joins exons together to form mature mRNA.

Question 7

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

Accepted Answer

The mRNA will be rapidly degraded and poorly translated.

Question 8

Which of the following best explains why bacterial translation can begin before transcription is complete?

Accepted Answer

Both transcription and translation occur in the cytoplasm, allowing ribosomes to access mRNA as it is synthesized.

Question 9

What is the role of the poly(A) tail in eukaryotic mRNA?

Accepted Answer

It protects the mRNA from degradation and aids in export from the nucleus.

Question 10

Which of the following is true about exons and introns in eukaryotic genes?

Accepted Answer

Introns are non-coding regions that are removed from the primary transcript.

Question 11

A researcher observes that a eukaryotic mRNA lacks a poly(A) tail. Which process was most likely disrupted?

Accepted Answer

RNA processing after the poly(A) signal sequence was transcribed

Question 12

Which of the following best describes the function of snRNPs in eukaryotic cells?

Accepted Answer

They recognize splice sites and help remove introns from pre-mRNA.

Question 13

Which sequence is most commonly found near the transcription start site in bacterial promoters?

Accepted Answer

-10 box and -35 box

Question 14

What is the immediate product of transcription in eukaryotes?

Accepted Answer

Primary transcript (pre-mRNA)

Question 15

Which of the following is a direct result of the formation of a hairpin structure in bacterial transcription termination?

Accepted Answer

The RNA transcript is released from RNA polymerase.

Question 16

A mutation in a bacterial promoter prevents sigma protein binding. What is the most likely outcome?

Accepted Answer

Transcription will not initiate for that gene.

Question 17

Which of the following is NOT a function of the untranslated regions (UTRs) in mature eukaryotic mRNA?

Accepted Answer

Coding for amino acids in the protein

Question 18

Which of the following best explains why the poly(A) tail is not encoded in the DNA template?

Accepted Answer

It is added enzymatically after the pre-mRNA is cleaved downstream of the poly(A) signal.

Question 19

Which of the following statements about translation in bacteria is correct?

Accepted Answer

Translation can begin before transcription is finished, allowing for rapid protein synthesis.

Question 20

Which hypothesis about how mRNA specifies amino acids is supported by experimental evidence?

Accepted Answer

Adapter molecules (such as tRNA) hold amino acids and interact with mRNA codons.

CH 17 p. 1: Transcription, RNA Processing, and Translation: Mechanisms and Comparisons

Study Guide - Practice Questions