Question

multiple choice question
which of these best describe a codon?

a triplet amino acid sequence.
a triplet mrna sequence which encodes an amino acid.
a triplet trna sequence which encodes an amino acid.

Explanation:

To determine the correct description of a codon, we analyze each option:

• Option 1: A codon is not an amino acid sequence. Amino acids are the building blocks of proteins, and codons are related to RNA sequences that code for amino acids. So this option is incorrect.
• Option 2: A codon is defined as a triplet of nucleotides (specifically in mRNA) that corresponds to a particular amino acid during protein synthesis. This matches the definition of a codon.
• Option 3: tRNA has anticodons, not codons. Anticodons on tRNA are complementary to codons on mRNA and are involved in bringing the correct amino acid to the ribosome. So this option is incorrect.

Answer:

B. A triplet mRNA sequence which encodes an amino acid.