Question

Describe the main characteristic features of Genetic Code.

Hint:

Remember, the genetic code is a universal, degenerate triplet code that is read without ambiguity and is essential for the synthesis of proteins.

Answer 1

The genetic code refers to the set of rules by which information encoded in DNA (or RNA) is translated into proteins. The main characteristic features of the genetic code are as follows:
1. Triplet Code:
Each amino acid in a protein is specified by a sequence of three nucleotide bases, known as a codon. The codons are read in sets of three from the mRNA during the process of translation.
2. Universality:
The genetic code is nearly universal. It is the same in almost all organisms, from bacteria to humans. This universality reflects the evolutionary common ancestry of all life forms.
3. Degeneracy (Redundancy):
The genetic code is degenerate, meaning that more than one codon can code for the same amino acid. For example, both UUU and UUC codons code for the amino acid phenylalanine.
4. Unambiguous:
Each codon specifies only one amino acid. There is no ambiguity in the interpretation of codons in the genetic code.
5. Start and Stop Codons:
The genetic code includes special codons known as the start codon (AUG), which signals the beginning of translation, and stop codons (UAA, UAG, UGA), which signal the end of translation.
6. Non-overlapping:
The genetic code is read in a non-overlapping manner, meaning that each nucleotide is part of only one codon, and codons do not overlap with each other.
7. Directionality:
The genetic code is read in the 5' to 3' direction during transcription and translation. This directionality is essential for the proper synthesis of proteins.