Question 1

Which of the following statements best describes the role of RNA in protein synthesis in eukaryotic cells?

Accepted Answer

RNA serves as an intermediary, carrying genetic information from DNA in the nucleus to the site of protein synthesis in the cytoplasm.

Question 2

Which base pairing occurs during RNA synthesis from a DNA template?

Accepted Answer

A with U and C with G

Question 3

Which category of RNA is responsible for binding an amino acid and depositing it into a growing protein chain?

Accepted Answer

Transfer RNA (tRNA)

Question 4

Which functional RNA provides a template for the synthesis of repetitive DNA telomere sequences?

Accepted Answer

Telomerase RNA

Question 5

What is the correct order of the four stages of bacterial transcription?

Accepted Answer

Promoter recognition, transcription initiation, chain elongation, chain termination

Question 6

In bacterial transcription, which DNA strand does RNA polymerase use to assemble a complementary, antiparallel strand of ribonucleotides?

Accepted Answer

Template strand

Question 7

Which region of a gene regulates the cessation of transcription?

Accepted Answer

Termination region

Question 8

What is the effect of rifampicin on bacterial RNA polymerase?

Accepted Answer

It inhibits RNA synthesis by preventing the formation of the first phosphodiester bond.

Question 9

Which subunit is required for the RNA polymerase core enzyme to efficiently bind the promoter and initiate RNA synthesis in bacteria?

Accepted Answer

Sigma subunit

Question 10

What is the function of alternative sigma subunits in bacterial RNA polymerase?

Accepted Answer

They allow the core enzyme to recognize different promoter regions.

Question 11

Which consensus sequence is found at the -10 position in bacterial promoters and is also known as the Pribnow box?

Accepted Answer

$$5'-TATAAT-3'$$

Question 12

During transcription initiation in bacteria, what is the first step after the holoenzyme makes a loose attachment to the promoter sequence?

Accepted Answer

Binding tightly to form the closed promoter complex

Question 13

At what point does the sigma subunit dissociate from the core enzyme during bacterial transcription?

Accepted Answer

After the first 8 to 10 RNA nucleotides have been joined

Question 14

Which mechanism of transcription termination in bacteria involves the formation of a hairpin structure in the mRNA?

Accepted Answer

Intrinsic termination

Question 15

What is the role of the rho protein in bacterial transcription termination?

Accepted Answer

It attaches to the rut site on mRNA and catalyzes the release of mRNA from RNA polymerase.

Question 16

Which of the following is NOT a function of the 5' cap added to eukaryotic mRNA?

Accepted Answer

Initiating polyadenylation at the 3' end

Question 17

Which consensus sequence is most commonly found in eukaryotic promoters and is also known as the Goldberg-Hogness box?

Accepted Answer

$$5'-TATAAA-3'$$

Question 18

Which protein complex binds to the TATA box during eukaryotic transcription initiation?

Accepted Answer

TFIID

Question 19

What is 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 transcription complex.

Question 20

Which of the following statements about chromatin-based regulation of transcription is correct?

Accepted Answer

Chromatin modification and remodeling are epigenetic processes that affect accessibility of transcription machinery to DNA.

Molecular Biology of Transcription and RNA Processing: Study Notes

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