Q: Which of the following equations correctly represents the Central Dogma of Molecular Genetics?

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

Question 1

Which of the following best describes the process of intrinsic (Rho-independent) transcription termination in bacteria?

Accepted Answer

A termination sequence is transcribed, causing the RNA to fold into a hairpin structure followed by a string of uracils, destabilizing the RNA-DNA duplex and releasing the transcript.

Question 2

In eukaryotic cells, which RNA polymerase is responsible for transcribing protein-coding genes?

Accepted Answer

RNA polymerase II

Question 3

What is the primary function of the 5’ methylguanosine cap added to eukaryotic mRNA?

Accepted Answer

It protects the mRNA from exonucleases, aids in export from the nucleus, and helps initiate translation.

Question 4

Which sequence is recognized by the cleavage and polyadenylation specificity factor (CPSF) during eukaryotic mRNA processing?

Accepted Answer

$$5'-AAUAAA-3'$$

Question 5

A researcher removes the 5’ cap and poly-A tail from an mRNA and inserts it into a eukaryotic cell. What is most likely to happen?

Accepted Answer

The molecule will be degraded by enzymes.

Question 6

Which of the following is NOT a modification made to eukaryotic mRNA before it is exported to the cytosol?

Accepted Answer

Removal of exons

Question 7

Which of the following statements about prokaryotic transcription is TRUE?

Accepted Answer

Translation of mRNA can begin before transcription has finished.

Question 8

What is the main difference between prokaryotic and eukaryotic gene structure?

Accepted Answer

Eukaryotic genes contain exons interrupted by introns, while prokaryotic genes are uninterrupted.

Question 9

Which of the following is required for Rho-dependent termination in bacteria?

Accepted Answer

The Rho factor binding to the rut site and moving along the RNA to break the RNA-DNA hybrid

Question 10

Which of the following best describes the role of snRNAs in spliceosome-dependent splicing?

Accepted Answer

They catalyze the splicing reaction by base pairing with splice sites.

Question 11

Which of the following is a consequence of a mutation in the conserved GU sequence at the 5’ splice site of an intron?

Accepted Answer

The exon will be excluded from the mature mRNA.

Question 12

Which of the following equations correctly represents the Central Dogma of Molecular Genetics?

Accepted Answer

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

Question 13

Which of the following is TRUE regarding the processing of eukaryotic pre-mRNA?

Accepted Answer

Exons are joined together after introns are removed.

Question 14

Which of the following is a function of the poly-A tail in eukaryotic mRNA?

Accepted Answer

It increases mRNA stability and aids in export from the nucleus.

Question 15

Which of the following statements about self-splicing introns is correct?

Accepted Answer

They have complex secondary structures that enable them to catalyze their own excision without proteins.

Question 16

Which of the following is a major difference between transcription termination in prokaryotes and eukaryotes?

Accepted Answer

In eukaryotes, RNA polymerase II transcribes well past the coding sequence, and the 3’ end is determined by RNA processing steps.

Question 17

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

Accepted Answer

Introns are removed by splicing, leaving only exons in the mature mRNA.

Question 18

Which of the following is TRUE about the coupling of transcription and translation in prokaryotes?

Accepted Answer

Translation can begin before transcription is complete.

Question 19

Which of the following is NOT a product of eukaryotic RNA polymerase III?

Accepted Answer

mRNA

Question 20

Which of the following best describes the role of the C-terminal domain (CTD) of RNA polymerase II?

Accepted Answer

It serves as a scaffold for organizing factors involved in pre-mRNA processing, including capping, polyadenylation, and intron removal.

Transcription and RNA Processing in Prokaryotes and Eukaryotes

Guida di studio - Domande di pratica

Study guide - Flashcard