They play huge role in organisms, every living organism needs proteins.
- enzymatic role ( they build enzymes which lower an activation energy in reactions and increase reaction speed)
- hormonal role (they build hormons)
- structural role (for example keratin)
- transport role ( for example hemoglobin)
- energetic role ( for example aleurone grains in plant cells or they are used to gain energy in human organism when it's out of lipids and carbohydrates)