(a) What is a genetic code? (b) Why did scientists feel the need to propose a genetic code? (c) Genetic code is said to be 'Universal'. Why?

Genetic Code: It is the sequence of three nitrogenous bases (codon) on mRNA that directs the sequence of amino acids during synthesis of proteins.

To provide complementarity between nucleotides and amino acids / to support the notion that change in nucleic acids was responsible for change in amino acids in proteins / to establish the correlation between genetic information and protein synthesis / to constitute a combination of four bases to code twenty amino acids.

As a codon from bacteria to human code for the same amino acid.