Final answer:
Keratin and collagen are both structural proteins that provide strength and flexibility to different parts of the body.
Step-by-step explanation:
Keratin and collagen are both types of structural proteins found in the human body. They have some similarities in that they provide strength and flexibility to different parts of the body. Keratin is a tough, fibrous protein found in the skin, hair, and nails, while collagen is a protein that forms the connective tissue in the body. Both keratin and collagen have an organic matrix material that contributes to their strength and flexibility.