FUNCTIONS OF PROTEIN

1. Proteins from the colloidal complex of the protoplasm and its organelles.
2. Most Abundant Protein in Organic World is RUBISCO or Ribulose biphosphate carboxylase.
3. Most Abundant Protein in Human Body is Collagen. Upto 6% of total protoplasm (50% of total protein).
4. Artificial Silk is a polysaccharide and not a protein.
5. Leather is almost pure collagen.
6. Ossein is Bone collagen.
7. Chondrin is Bluish white ground substance of cartilage mostly formed of collagen.  .
8. Collagen provides tensile strength to connective tissue, tendons, cartilage and bones.
9. Keratin is the main component of external protective structures like dead layers of skin, hair, scales, feathers, nails, claws, hoofs, horns, beaks.
10. Fibroin or silk fibre forms cocoon covering of silkworm. Spider web is also made of fibroin.
11. Actin and myosin constitute contractile system of muscles.
12. P-proteins found in sieve tube cytoplasm which probably aid in solute movement.
13. Microtubules are formed of a-tubulin and b-tubulin.
14. Some hormones (insulin, glucagon, relaxin, HCG, TSH, FSH) are formed of proteins.
15. Immunoglobulins are proteinaceous substances produced by lymphocytes that defend the body against infections.
16. Prothrombin & fibrinogen involved in blood clooting.
17. Resilin occurs in the wing of insects.
18. Monellin present in berries of African plant Dioscoreophyllum cumminsii.
19. Memory seems to be stored in the form of protein.

Protein test = Burette test