Final answer:
Collagen is the fibrous protein that gives skin form and strength, and it plays a critical role in the integrity and structure of connective tissues. Collagen and elastin are key structural proteins that do not dissolve in water, forming tough, insoluble fibers that contribute to the body's framework.
Step-by-step explanation:
The fibrous protein that gives skin form and strength is collagen. Collagen fibers are essential components of the extracellular matrix found in various connective tissues, including the skin. They provide tensile strength to the tissue, preventing it from being torn or separated from the surrounding tissues. In the skin, specifically, collagen contributes to the dermis layer, which is responsible for the skin's strength and elasticity.
Fibrous proteins such as collagen and elastin are insoluble in water and are arranged in long parallel chains, forming tough materials that make up the structural components of tissues like tendons, bone, hair, and skin. Keratin is another type of fibrous protein that is found in the hair, nails, and outer layer of the skin, while elastin fibers provide flexibility, allowing tissues to stretch and return to their original shape.