Question 1

Which of the following best describes the process of translation in cells?

Accepted Answer

mRNA template-directed biosynthesis of proteins involving all types of RNA

Question 2

During translation, in which direction is the mRNA read by the ribosome?

Accepted Answer

From the 5' end to the 3' end

Question 3

What is the correct order of the three repeating themes in DNA replication, transcription, and translation?

Accepted Answer

Initiation, elongation, termination

Question 4

Which of the following equations correctly represents the activation of an amino acid for incorporation into proteins?

Accepted Answer

$$\mathrm{Amino\ acid} + \mathrm{ATP} + \mathrm{tRNA} \rightarrow \mathrm{Aminoacyl-tRNA} + \mathrm{AMP} + \mathrm{PP_i}$$

Question 5

The anticodon loop of tRNA contains a trinucleotide sequence that is complementary to which part of the mRNA?

Accepted Answer

The codon

Question 6

Which codon serves as the universal start codon for translation in most organisms?

Accepted Answer

AUG

Question 7

What is the significance of the 'wobble' position in the genetic code?

Accepted Answer

It allows a single tRNA to recognize multiple codons due to flexibility at the 5' anticodon position

Question 8

In E. coli, what is the approximate time required to synthesize a 300-residue protein?

Accepted Answer

20 seconds

Question 9

Which of the following statements about ribosomes is correct?

Accepted Answer

The bacterial 70S ribosome is composed of 50S and 30S subunits

Question 10

Which of the following is a function of the Shine-Dalgarno sequence in prokaryotic mRNA?

Accepted Answer

It helps position the ribosome for correct initiation of translation

Question 11

What is the role of aminoacyl-tRNA synthetase in protein synthesis?

Accepted Answer

It couples a specific amino acid to its corresponding tRNA

Question 12

Which of the following is NOT a stop codon in the genetic code?

Accepted Answer

AUG

Question 13

A synthetic polyribonucleotide with a 5:1 ratio of CDP to ADP stimulates the incorporation of several amino acids in a cell-free translation system. What does this experiment reveal about the genetic code?

Accepted Answer

The nucleotide composition of coding triplets influences which amino acids are incorporated

Question 14

Which of the following best explains why the genetic code is described as 'degenerate'?

Accepted Answer

Multiple codons can encode the same amino acid

Question 15

Which of the following drugs inhibits eukaryotic translation by catalyzing the addition of an ADP-ribose group to a modified histidine on EF2?

Accepted Answer

Diphtheria toxin

Question 16

What is the primary function of SNARE proteins in eukaryotic cells?

Accepted Answer

They mediate membrane fusion during vesicle transport

Question 17

In the process of bacterial protein secretion, what is the role of the N-terminal signal sequence?

Accepted Answer

It directs the protein to the membrane or for secretion

Question 18

Which of the following statements about polyribosomes is correct?

Accepted Answer

Multiple ribosomes can simultaneously translate a single mRNA molecule

Question 19

Which of the following best describes the coupling of transcription and translation in E. coli?

Accepted Answer

Translation begins before transcription is complete due to the lack of a nuclear membrane

Question 20

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

Accepted Answer

Eukaryotes use a 5'-methylguanosine cap to initiate translation, while prokaryotes use the Shine-Dalgarno sequence

Translation and Posttranslational Protein Processing: Information Decoding in the Cell

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