Q: Which of the following equations correctly represents the formation of a phosphodiester bond during RNA synthesis?

$$\text{(NMP)}_{n} + \text{NTP} \rightarrow \text{(NMP)}_{n+1} + PP_{i}$$

Question 1

Which of the following best describes the Central Dogma of molecular biology?

Accepted Answer

DNA is transcribed into RNA, which is then translated into protein.

Question 2

During transcription in prokaryotes, which of the following is responsible for recognizing the promoter region and initiating transcription?

Accepted Answer

Sigma factor

Question 3

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

Accepted Answer

It signals the termination of transcription.

Question 4

A mutation in the -10 region of a bacterial promoter is most likely to affect which process?

Accepted Answer

Binding of RNA polymerase holoenzyme to DNA

Question 5

Which of the following statements about RNA polymerase is TRUE?

Accepted Answer

RNA polymerase synthesizes RNA in the 5’ to 3’ direction and does not require a primer.

Question 6

Which of the following best explains why eukaryotic genes are typically larger and more complex than prokaryotic genes?

Accepted Answer

Eukaryotic genes contain introns and extensive regulatory regions.

Question 7

Which of the following is a correct description of the difference between the coding and template strands of DNA during transcription?

Accepted Answer

The coding strand has the same sequence as the RNA transcript (except T is replaced by U), while the template strand is used to synthesize the RNA.

Question 8

A researcher discovers a new eukaryotic gene that produces two different proteins in different cell types. Which process most likely explains this observation?

Accepted Answer

Alternative splicing

Question 9

Which of the following equations correctly represents the formation of a phosphodiester bond during RNA synthesis?

Accepted Answer

$$	ext{(NMP)}_{n} + 	ext{NTP} ightarrow 	ext{(NMP)}_{n+1} + PP_{i}$$

Question 10

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

Accepted Answer

Eukaryotes have three RNA polymerases, while prokaryotes have one.

Question 11

A mutation eliminates the function of the Rho protein in a bacterial cell. Which of the following is most likely to occur?

Accepted Answer

Some transcripts will fail to terminate properly, leading to abnormally long RNAs.

Question 12

Which of the following best describes the role of the polyA tail in eukaryotic mRNA?

Accepted Answer

It protects the mRNA from degradation and is required for export from the nucleus.

Question 13

Which of the following is a property of the sugar found in RNA but not in DNA?

Accepted Answer

It has a hydroxyl group at the 2’ carbon.

Question 14

Which of the following is true regarding the directionality of RNA synthesis?

Accepted Answer

RNA is synthesized in the 5’ to 3’ direction, using the 3’ to 5’ DNA template strand.

Question 15

Which of the following best explains why only a small percentage of the human genome codes for proteins?

Accepted Answer

Most of the human genome consists of introns, intergenic regions, and repetitive DNA.

Question 16

Which of the following is a correct sequence of events during eukaryotic transcription initiation?

Accepted Answer

TFIID binds the TATA box, then TFIIB, TFIIF, RNA pol II, TFIIE, and TFIIH assemble to form the preinitiation complex.

Question 17

A scientist is studying a gene with a consensus promoter sequence of TTGACA at -35 and TATAAT at -10. Which organism is this gene most likely from?

Accepted Answer

A bacterium (prokaryote)

Question 18

Which of the following best describes the function of topoisomerase during transcription?

Accepted Answer

It relieves supercoiling ahead of the transcription bubble.

Transcription: DNA to RNA in Prokaryotes and Eukaryotes

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