When does protein catabolism usually occur?

Answer 1

Protein catabolism is the breakdown of the proteins into the amino acids which are the basic constituents of the protein. In digestion process the proteins get converted into amino acids and used for the repair and building process of cells. The excess of amino acid get converted into fat and sugar and get stored into liver. Due to illness or prolonged starvation when the body does not get adequate energy, this excess of amino acid in the form of fats or sugar get breakdown and provides energy.