Describe the secondary and tertiary structure of a protein

The secondary structure of a protein refers to the folding or coiling of a protein. There are 2 main secondary structures. 1) alpha helix – this is held by hydrogen bonds and forms a coiled spring shape (like a slinky). 2) Beta pleated sheets – this is also held by hydrogen bonds and forms adjacent pleated sheets. The tertiary structure refers to the 3D shape.This can be twisted and manipulated to achieve its lowest energy state. The two main shapes are globular (circle shape – most enzymes) or fibrous (strands - like collagen). There are many stabilising forces.1. disulfide bridges 2. hydrogen bonds 3. ionic bonds 4. Van Der walls