| Fibrous Proteins | Globular Proteins |
| 1. Consist of linear thread-like molecules which tend to lie side by side to form fibrelike structure. | 1. Polypeptide chain * folded, around itself forming almost spheroidal shape. |
| 2. Insoluble in water. | 2. Soluble in water. |
| 3. Keratin in hair, fibroin in silk, etc. | 3. Albumin in eggs, insulin, etc. |
Denaturation of Proteins
When a protein in its native form, is subjected to a change in temperature or change in pH, the hydrogen bond are *****. Due to this, globules unfold and helix get uncoiled and protein loses its biological activity. This is called denaturation of protein. During denaturation 2° and 3° structures are destroyed but 1° structures remain intact, e.g., coagulation of egg white on boiling, curdling of milk, etc.
