Question 1

Which of the following statements best describes the direction of RNA synthesis during transcription?

Accepted Answer

RNA is synthesized in the 5' to 3' direction, using the template strand as a guide.

Question 2

In prokaryotic transcription termination, which structure is responsible for Rho-independent termination?

Accepted Answer

A hairpin loop followed by a series of uracil residues in the RNA transcript.

Question 3

Which equation correctly represents the number of possible codons given the triplet nature of the genetic code?

Accepted Answer

$$4^3 = 64$

Question 4

A mutation changes the DNA sequence from CTT to CAT in the hemoglobin gene. What is the effect on the protein product?

Accepted Answer

The protein will have valine instead of glutamic acid, causing sickle-cell disease.

Question 5

Which of the following is NOT a feature of prokaryotic mRNA?

Accepted Answer

It is usually monocistronic.

Question 6

What is the function of the Shine-Dalgarno sequence in prokaryotes?

Accepted Answer

It facilitates the binding of the ribosome to the mRNA for translation initiation.

Question 7

Which consensus sequence is commonly found at the -10 region of strong E. coli promoters?

Accepted Answer

$$TATAAT$$

Question 8

Which of the following statements about eukaryotic mRNA maturation is correct?

Accepted Answer

Eukaryotic mRNA must be spliced to remove introns before it is functional.

Question 9

Which of the following is a correct pairing according to the wobble hypothesis?

Accepted Answer

I (inosine) pairs with A, U, or C at the wobble position.

Question 10

Which ribosomal subunit in prokaryotes contains the peptidyl transferase activity?

Accepted Answer

23S subunit

Question 11

During eukaryotic translation initiation, what sequence is used to identify the correct AUG start codon?

Accepted Answer

Kozak sequence

Question 12

Which of the following best describes the role of the spliceosome?

Accepted Answer

It removes introns from pre-mRNA and joins exons together.

Question 13

Which equation represents the relationship between the number of possible codons and the number of bases per codon?

Accepted Answer

$$n^b$$

Question 14

Which of the following is a real-life example of a missense mutation?

Accepted Answer

A mutation in hemoglobin DNA changing CTT to CAT, resulting in sickle-cell disease.

Question 15

Which of the following is NOT a function of tRNA?

Accepted Answer

Catalyzing peptide bond formation.

Question 16

Which of the following is true regarding the structure of eukaryotic ribosomes?

Accepted Answer

They are composed of 40S and 60S subunits, forming an 80S ribosome.

Question 17

Which of the following is a correct description of the promoter for RNA polymerase II?

Accepted Answer

It contains a TATA box located approximately -25 bp upstream of the transcription start site.

Question 18

Which of the following best explains why eukaryotic mRNA cannot be translated while it is being transcribed?

Accepted Answer

Transcription occurs in the nucleus and translation occurs in the cytoplasm.

Question 19

Which of the following is a feature of the wobble hypothesis?

Accepted Answer

It allows a single tRNA to recognize multiple codons due to flexible base pairing at the third position.

Transcription, mRNA Processing, and Translation in Prokaryotes and Eukaryotes

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