The main functions of proteins are to provide energy to the body when consumed in the diet, participate in building new body tissues and are able to promote resistance and elasticity to the tissues.
They may also act as catalysts for chemical reactions (enzymes). Proteins can act in the regulation of hormones and also in the body's defense systems (antibodies have proteins in their composition), fighting viruses, bacteria and other pathogens.
Liver is not involved in the product of blood clotting protein rather it is involved in the production of two hormones insulin and glucagon that play roles in regulating blood sugar.
