Q21 of 30 Page 1

What is the genetic basis for proof that codon is a triplet and is read in a contiguous manner without punctuations?

There are four bases which code for 20 amino acids. In order to code for all the 20 amino acids, the code should be made up of 3 nucleotides. A permutation of 4 x 4 x 4 = 64 is obtained which is more than required. If the codon consists of four letters then only sixteen (4 x 4 = 16) codes are possible, which is less than the required.


As ribosome moves on mRNA the codons are read in a contiguous fashion.


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