What kind of proteins form the basis of epidermal tissues like hair and nails?

Epidermal tissues such as hair and nails are primarily composed of keratin proteins. Keratin is a tough, fibrous protein that provides structural strength and protection to these tissues. It plays a crucial role in the durability and resilience of hair and nails, offering resistance to wear and tear as well as environmental damage. The unique structure of keratin allows it to aggregate into filaments, giving rise to the hard, resilient characteristics that are essential for the function of hair and nails.

In contrast, collagen proteins primarily function in providing support and structure in connective tissues such as skin, cartilage, and bones, rather than forming the structural basis of epidermal tissues. Other proteins like fibronectin are involved in cell adhesion and are part of the extracellular matrix, while cathodic proteins are not a recognized category in the context of epidermal tissues. This understanding emphasizes the specific role of keratin in the formation and maintenance of epidermal structures.