What are essential and non-essential amino acids ? Give two examples of each type.

Explanation

There are 20 commonly occurring `alpha`-amino acids. These can be classified as essential and non-essential amino acids.
Essential amino acids : Amino acids which cannot be synthesised in the body and must therefore be obtained through diet are known as essential amino acids.
For example, Lysine, valine, leucine etc.
Non-essential amino acids : Amino acids which can be synthesised in the body are known as non-essential amino acids.
For example, Glycine, alanine, proline etc.