A sequence of how many nucleotides in messenger RNA makes a codon for an amino acid :-
A
Four
B
One
C
Two
D
Three
The answer is D.
Solution
The genetic code is a triplet code: a sequence of three consecutive nucleotides (bases) on mRNA codes for one amino acid. This group of three is called a codon. There are 4 bases (A, U, G, C). Codons of one base would give only $4^1 = 4$ combinations and codons of two bases only $4^2 = 16$, which are fewer than the 20 amino acids. Codons of three bases give $4^3 = 64$ combinations, which is enough to code all 20 amino acids along with start and stop signals. So a sequence of three nucleotides makes a codon.
ConceptTriplet codon
Biomolecules in past papers
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