Question 1

Which of the following best describes the direction in which a ribosome reads an mRNA molecule during translation?

Accepted Answer

5' to 3'

Question 2

A tRNA with the anticodon 3' UAC 5' will pair with which mRNA codon, and what amino acid will it carry?

Accepted Answer

5' AUG 3', Methionine

Question 3

Given the DNA template strand 3' TAC GGC TTA CTG AAC TTT CAA TTA 5', what is the corresponding mRNA sequence?

Accepted Answer

5' AUG GCC AAU GAC UUG AAA GUU AAU 3'

Question 4

Which of the following statements about codons is TRUE?

Accepted Answer

There are 64 possible codons, but only 20 amino acids.

Question 5

A mutation changes the codon UAU (tyrosine) to UAA in an mRNA. What is the most likely result?

Accepted Answer

Translation will terminate prematurely.

Question 6

During translation elongation, which site of the ribosome does the incoming charged tRNA enter first?

Accepted Answer

A site

Question 7

If the mRNA sequence is 5' AUG GGC AAU GAC UUU CAA UAA 3', what is the fourth amino acid in the resulting polypeptide?

Accepted Answer

Aspartic acid

Question 8

Which of the following best explains why multiple ribosomes can translate a single mRNA molecule simultaneously?

Accepted Answer

Ribosomes attach to the mRNA at different points, forming a polyribosome (polysome) complex.

Question 9

A tRNA is charged with the amino acid alanine. Its anticodon is 3' CGU 5'. What is the corresponding mRNA codon?

Accepted Answer

5' GCA 3'

Question 10

Which of the following is NOT a function of aminoacyl tRNA synthetase?

Accepted Answer

Catalyzing peptide bond formation between amino acids

Question 11

A patient has a mutation that prevents the removal of the signal sequence from a newly synthesized protein. What is the most likely consequence?

Accepted Answer

The protein will remain embedded in the membrane or be mislocalized.

Question 12

Which of the following best describes the relationship between the coding strand of DNA and the mRNA produced during transcription?

Accepted Answer

The mRNA is identical to the coding strand except that T is replaced by U.

Question 13

Which of the following is the correct sequence of events in the central dogma of molecular biology?

Accepted Answer

DNA → RNA → Protein

Question 14

A ribosome is translating an mRNA and encounters the codon 5' UGA 3'. What happens next?

Accepted Answer

A release factor binds, terminating translation.

Question 15

Which of the following statements about tRNA is FALSE?

Accepted Answer

tRNA molecules are translated into proteins.

Question 16

If the mRNA codon is 5' GAA 3', what is the sequence of the anticodon on the tRNA that will bind to it?

Accepted Answer

3' CUU 5'

Question 17

Which of the following best explains the redundancy of the genetic code?

Accepted Answer

Some amino acids are specified by more than one codon.

Question 18

A scientist mutates the start codon (AUG) of an mRNA to UUG. What is the most likely effect on translation?

Accepted Answer

Translation will initiate at the next AUG codon downstream.

Question 19

Which of the following is a function of the ribosome during translation?

Accepted Answer

It catalyzes the formation of peptide bonds between amino acids.

Question 20

A protein is destined to be secreted from the cell. Where does its translation begin and where is it completed?

Accepted Answer

Begins in the cytoplasm, completed on the rough endoplasmic reticulum

Translation: Decoding mRNA into Protein

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