An organism uses 20 amino acids while its DNA is made up of 6 types of nitrogenous bases. What would be the minimum size of a codon?

Question

An organism uses 20 amino acids while its DNA is made up of 6 types of nitrogenous bases. What would be the minimum size of a codon? (A) 6 (B) 4 (C) 3 (D) 2

Tardigrade Admin · Accepted Answer

As there are 20 amino acids thus there must be atleast 20 unique combinations of the bases. If the code is singlet i.e., consists of only one base then possible codons can be (6)1 = 6, which is far less than the required number i.e., 20. If the code is doublet (made up of combination of two bases) then the possible codons can be (6)2 = 36. 36 is sufficient (even more) than the required number. Here some amino acid could be coded by more than one codon and some codons will function as start and stop codons.

Q. An organism uses $20$ amino acids while its $D N A$ is made up of $6$ types of nitrogenous bases. What would be the minimum size of a codon?

$6$

$4$

$3$

$2$

Q. An organism uses 20 amino acids while its DNA is made up of 6 types of nitrogenous bases. What would be the minimum size of a codon?

6

4

3

2

Q. An organism uses $20$ amino acids while its $D N A$ is made up of $6$ types of nitrogenous bases. What would be the minimum size of a codon?

$6$

$4$

$3$

$2$