Question

A. What is denaturation of proteins?
B. What are essential amino acids? Give one example.

Answer 1

Hint: We know that Proteins are huge biomolecules, or macromolecules composed of amino acid residues. The important blocks of our body structure and for their functioning require protein. The amount of protein is supplied to our body through food products such as pulses, cheese, milk, meat, nuts etc.

Complete answer:
-Denaturation of proteins
We can define denaturation as the destruction of the tertiary structure of a protein molecule and the development of random polypeptide chains. Denaturation of proteins is one of the phenomena that affects the disturbance of stability and structure of the protein.
Denaturation is a process in which proteins lose their state, and their function because of change in pH or temperature. Denaturation could easily change in secondary, tertiary and quaternary structure of proteins.
Let us discuss some of causes for the denaturation to occur,
Denaturation occurs due to heating, exposure to acid (or) bases.
Heavy metal poisoning such as lead, cadmium changes the structure of proteins by binding to functional groups on the surface of protein.
Physical/Chemical changes could also cause denaturation of proteins.
Change in temperature could also cause denaturation of protein.
- Essential amino acid with one example:
We know that organic compounds, which combine to form protein, are called amino acids. When proteins are broken down, amino acids are eliminated. Amino acids help the human body to make proteins break down food.
Essential amino acid is one of the types of amino acid, which could not be synthesized from metabolic intermediates. They are taken from an exogenous diet because the human body lacks metabolic pathways that are necessary to synthesize these acids.
There are nine essential amino acids. Some of them are Valine, threonine, lysine and histidine.

Note:
We must know that the curdling of curd is an example of denaturation of proteins, where the formation of lactic acid by microbial action leads to denaturation.