Q: Given the following template DNA sequence (3' to 5'): 3'-TAC GGA TTT CCG-5', what is the corresponding mRNA sequence (5' to 3')?

$$5'\text{-}AUG\ GGA\ UUU\ CCG\text{-}3'$$

Question 1

Which of the following best describes the relationship between genes and proteins according to the central dogma of molecular biology?

Accepted Answer

Genes (DNA) are transcribed into mRNA, which is then translated into proteins.

Question 2

A mutation causes a single nucleotide insertion in the coding region of a gene. What is the most likely consequence for the resulting protein?

Accepted Answer

A frameshift will occur, altering the reading frame and likely resulting in a nonfunctional protein.

Question 3

Which of the following statements about the genetic code is CORRECT?

Accepted Answer

The genetic code is nearly universal and redundant, with most amino acids specified by more than one codon.

Question 4

Given the following template DNA sequence (3' to 5'): 3'-TAC GGA TTT CCG-5', what is the corresponding mRNA sequence (5' to 3')?

Accepted Answer

$$5'	ext{-}AUG\ GGA\ UUU\ CCG	ext{-}3'$$

Question 5

Which of the following best explains the concept of 'wobble' in tRNA anticodon-codon pairing?

Accepted Answer

The third base of the codon can form non-standard base pairs with the first base of the anticodon, allowing some tRNAs to recognize multiple codons.

Question 6

Which of the following is NOT a component required for translation?

Accepted Answer

DNA polymerase

Question 7

What is the primary function of aminoacyl-tRNA synthetase in translation?

Accepted Answer

It attaches the correct amino acid to its corresponding tRNA, forming an aminoacyl-tRNA.

Question 8

Which of the following best describes the difference in translation initiation between prokaryotes and eukaryotes?

Accepted Answer

Prokaryotes use a Shine-Dalgarno sequence to align the ribosome with the start codon, while eukaryotes use the 5' cap and scan for the start codon.

Question 9

Which of the following best describes the role of the ribosome during translation?

Accepted Answer

It catalyzes the formation of peptide bonds between amino acids, ensuring the correct reading frame is maintained.

Question 10

A patient has a mutation that prevents the nuclear membrane from functioning properly. Which of the following is a likely consequence in a eukaryotic cell?

Accepted Answer

Translation will begin before transcription is complete, similar to prokaryotes.

Question 11

Which of the following best describes the colinearity of genes and proteins?

Accepted Answer

The sequence of nucleotides in a gene directly determines the linear sequence of amino acids in a protein.

Question 12

Which of the following is the correct order of events during translation?

Accepted Answer

Initiation, elongation, termination

Question 13

A tRNA molecule has the anticodon $$5'	ext{-}GAA	ext{-}3'. $$Which mRNA codon will it recognize, considering standard base pairing?

Accepted Answer

$$5'	ext{-}CUU	ext{-}3'$$

Question 14

Which level of protein structure is primarily determined by the sequence of amino acids?

Accepted Answer

Primary structure

Question 15

A gene encodes a protein with the following amino acid sequence: Met-Ser-Leu. Which of the following mRNA sequences could code for this protein? (Use the genetic code: Met = AUG, Ser = UCU/UCC/UCA/UCG/AGU/AGC, Leu = UUA/UUG/CUU/CUC/CUA/CUG)

Accepted Answer

$$5'	ext{-}AUG\ UCU\ CUA	ext{-}3'$$

Question 16

Which of the following statements about tRNA structure and function is CORRECT?

Accepted Answer

tRNA molecules have a cloverleaf structure with an anticodon loop that pairs with mRNA codons and an acceptor stem that binds amino acids.

Question 17

If a mutation changes a codon from UAU to UAA, what is the likely effect on translation?

Accepted Answer

Translation will terminate prematurely because UAA is a stop codon.

Question 18

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

Accepted Answer

Some amino acids are coded by more than one codon.

Question 19

A researcher isolates a ribosome from a eukaryotic cell and observes that it is located in the cytoplasm. Which of the following is a likely function of this ribosome?

Accepted Answer

Translating mRNA into protein

Question 20

A DNA sequence is mutated such that the reading frame is shifted. Which of the following best describes the likely outcome?

Accepted Answer

The amino acid sequence downstream of the mutation will be altered, often resulting in a nonfunctional protein.

Genetics Study Guide: Translation, Genetic Code, and Protein Synthesis

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