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Which one of the following pairs of codons is correctly matched with their function or the signal for the particular amino acid?
A
AUG, ACG - Start/Methionine
B
UUA, UCA - Leucine
C
GUU, GCU - Alanine
D
UAG, UGA - Stop
Detailed Solution
Out of 64 codons, 61 code for amino acids and 3 do not code for any amino acid; these three are the stop (terminator) codons: UAA, UAG and UGA.
So UAG and UGA are both stop codons, and this pair is correctly matched.
AUG codes for methionine and also acts as the start codon, but ACG codes for threonine.
UUA codes for leucine, but UCA codes for serine.
GCU codes for alanine, but GUU codes for valine.
In each of the other pairs only one codon matches the function given, so the correct pair is UAG, UGA - Stop.
So UAG and UGA are both stop codons, and this pair is correctly matched.
AUG codes for methionine and also acts as the start codon, but ACG codes for threonine.
UUA codes for leucine, but UCA codes for serine.
GCU codes for alanine, but GUU codes for valine.
In each of the other pairs only one codon matches the function given, so the correct pair is UAG, UGA - Stop.