Question

A strand of DNA that is 36 nucleotides long codes for how many amino acids?

Answer 1

Answer:

See answer below

Explanation:

Hi there,

Assuming this DNA strand is fully capable of being mature mRNA (5' m7G cap and PolyA tail), nucleotides lead to an mRNA codon, which is 3 nucleotides per codon. In turn, 1 codon leads to 1 amino acid. However, as a single strand, it must be capable of terminating translation, which always requires a stop codon, and thus 3 nucleotides. Hence, we must subtract this from the total amount of codons first.

$36 \ ncltd \ \frac{1 \ codon}{3 \ ncltd} = 12 \ codon\\12 \ codon - 1 \ codon \ = 11 \ codon\\11 \ codons\ \frac{1 A.A.}{1 \ codon} = 11 \ A. A.$

Hence, only 11 amino acids will be coded by a single DNA strand 36 ncltd long.

thanks,