Question 1

Which of the following RNA species is directly involved in the translation of the genetic code into amino acids during protein synthesis?

Accepted Answer

tRNA

Question 2

Which of the following statements best describes the main difference between transcription in prokaryotes and eukaryotes?

Accepted Answer

Transcription occurs in the nucleus in eukaryotes, and mRNA is transported to the cytoplasm for translation.

Question 3

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

Accepted Answer

RNA polymerase II

Question 4

A mutation occurs in the TATA box of a eukaryotic gene promoter. What is the most likely consequence?

Accepted Answer

RNA polymerase II will not efficiently bind, reducing transcription initiation.

Question 5

Which of the following best describes the function of enhancer sequences in eukaryotic transcription?

Accepted Answer

They increase the level of transcription by binding activator proteins and facilitating interaction with the promoter.

Question 6

Which of the following is a correct pairing of RNA polymerase and the RNA class it transcribes in eukaryotes?

Accepted Answer

RNA polymerase II – mRNA

Question 7

Which of the following sequence elements is most commonly found at approximately position −25 relative to the transcription start site in eukaryotic promoters?

Accepted Answer

TATA box

Question 8

A researcher is studying a gene with two internal promoter elements, box A and box B, located downstream of the transcription start site. Which gene is most likely being studied?

Accepted Answer

A tRNA gene

Question 9

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

Accepted Answer

They are required for the transcription of all or many genes and are present in all cells.

Question 10

Which of the following is true regarding the sense (coding) and antisense (template) DNA strands during transcription?

Accepted Answer

The RNA transcript has the same sequence as the sense strand, except uracil replaces thymine.

Question 11

Which of the following best explains why eukaryotic mRNA must be processed before translation?

Accepted Answer

Eukaryotic mRNA contains introns that must be removed.

Question 12

Which of the following is a function of small nucleolar RNAs (snoRNAs)?

Accepted Answer

Modification of rRNA

Question 13

A mutation in the upstream control element (−100 to −150) of an rRNA gene would most likely affect which process?

Accepted Answer

Efficiency of transcription by RNA polymerase I

Question 14

Which of the following best describes the termination mechanism for RNA polymerase III in eukaryotes?

Accepted Answer

It terminates at a string of uracils in the transcript without a stem-loop structure.

Question 15

Which of the following is a correct description of the assembly of the Class II transcription initiation complex?

Accepted Answer

TFIID binds the TATA box, followed by the sequential addition of TFIIA, TFIIB, TFIIF, RNA Pol II, TFIIE, and TFIIH.

Question 16

Which of the following best explains the function of silencer sequences in eukaryotic transcription?

Accepted Answer

They bind repressor proteins that bend DNA to reduce transcription.

Question 17

A gene contains a GC-rich box at position −90, a CAAT box at −80, and a TATA box at −25. Which RNA polymerase is most likely to transcribe this gene?

Accepted Answer

RNA polymerase II

Question 18

Which of the following is a unique feature of eukaryotic RNA polymerase II compared to bacterial RNA polymerase?

Accepted Answer

It contains subunits homologous to bacterial polymerase and several additional subunits.

Question 19

Which of the following best describes the function of microRNAs (miRNAs) in eukaryotic cells?

Accepted Answer

They repress translation by binding to target mRNAs.

Question 20

A mutation prevents the binding of TFIIIA to box C of a 5S rRNA gene. What is the most likely outcome?

Accepted Answer

TFIIIC will not bind box A, and RNA polymerase III will not be recruited.

Transcription in Eukaryotes: RNA Classes, Promoters, and Initiation Complexes

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