What type of keratin is found in hair?

• A. Soft keratin
• B. Hard keratin
• C. Elastic keratin
• D. Liquid keratin

Answer: (B)

Hair is composed primarily of hard keratin, which is a tougher and more resilient form of keratin compared to soft keratin. Hard keratin is characterized by its dense and fibrous structure, which provides strength and durability, making it ideal for the structural components of hair, nails, and the outer layer of the skin. This type of keratin is rich in disulfide bonds, which contribute to the rigidity and resistance to degradation, ensuring that hair can withstand various environmental factors without easily breaking or losing its shape.

Soft keratin, in contrast, is found in areas like the dermis of the skin, where flexibility and softness are more desirable. Elastic keratin is not a recognized type of keratin in the context of skin and hair structure, and liquid keratin is not an appropriate descriptor in this context, as keratin is a protein that solidifies into a fibrous form. Thus, the fundamental properties of hard keratin make it the defining component of hair, providing the necessary strength and protective qualities.