Question

What is codon and how many nitrogen bases are there in one of them?

Answer 1

Hint: Cells decode mRNAs by reading nucleotides in groups of three, called codons. When reading codons from the nucleotide sequence, they are read one after the other and do not overlap.

Complete answer:
Codon is a sequence of three DNA or RNA nucleotides corresponding to a specific amino acid or stop signal during protein synthesis. DNA and RNA molecules are written in four nucleotide languages, while proteins are written in a 20-amino-acid script.

Codons provide a key that allows these two languages to be translated into one another. Each codon corresponds to a single amino acid (or stop signal) and the whole set of codons is called the genetic code. The genetic code includes 64 possible permutations or combinations of three-letter nucleotide sequences which can be made from four nucleotides.

Of the 64 codons, 61 are amino acids, and three are stop signals. For example, codon CAG is an amino acid called glutamine, and TAA is a stop codon. The genetic code is described as degenerate or redundant because more than one codon can be encoded by a single amino acid.

The codon is a set of three pairs of nitrogen bases. Three bases actually code for an amino acid, but the DNA requires that the three bases that do the coding are linked to their pair. A-T, T-A, G-C. One amino acid is coded using six nitrogen bases. So the codon codes for the amino acid, requiring a total of six nitrogen bases.

Note: Here are some of the features of the codons:
- Most codons are an amino acid
- The end of the protein is three stop codons
- The amino acid methionine is encoded by a single starting codon, AUG, which marks the beginning of the protein.