They are large chemical molecules.
They contain carbon, hydrogen, oxygen, and nitrogen.
Nitrogen is the most essential element in proteins.
Some proteins may also contain sulfur and phosphorus.
Amino acids are the simple, smaller units of
proteins.
Proteins provide chemical material for the growth and repair of body cells and tissues.
In the time of emergency, they may also be oxidized to release energy.
Foods rich in proteins include lean meat, fat-free muscles, fish, eggs, milk, cheese, nuts, beans, and peas. etc.
A deficiency of proteins leads to weakness but its severe deficiency causes the two diseases.