Which term describes a three-base sequence in DNA that codes for an amino acid?

Which term describes a three-base sequence in DNA that codes for an amino acid?

• A. Allele
• B. Diploid
• C. Codon (triplet)
• D. Chromosome

Answer: (C)

A codon is a three-base sequence that specifies a particular amino acid during protein synthesis. In DNA or its mRNA copy, the genetic code reads these triplets one by one in translation, and each codon matches a tRNA carrying the corresponding amino acid. Because there are 64 possible triplets but only 20 amino acids, some amino acids are encoded by more than one codon, a feature called redundancy. There are also specific codons that signal the start of translation and the stop of the growing polypeptide chain. Other terms describe different genetic concepts: an allele is a variant form of a gene; diploid refers to having two sets of chromosomes; a chromosome is a long DNA molecule carrying many genes. These do not describe the three-base code that directly determines which amino acid is added.

A codon is a three-base sequence that specifies a particular amino acid during protein synthesis. In DNA or its mRNA copy, the genetic code reads these triplets one by one in translation, and each codon matches a tRNA carrying the corresponding amino acid. Because there are 64 possible triplets but only 20 amino acids, some amino acids are encoded by more than one codon, a feature called redundancy. There are also specific codons that signal the start of translation and the stop of the growing polypeptide chain.

Other terms describe different genetic concepts: an allele is a variant form of a gene; diploid refers to having two sets of chromosomes; a chromosome is a long DNA molecule carrying many genes. These do not describe the three-base code that directly determines which amino acid is added.