Why is keratin an important layer of defense against infection?

• A. Keratin is hydrophobic which keeps the skin & hair dry which decreases microbial growth.
• B. Keratin is the top layer of skin that regularly flakes off, removing microbes from the skin's surface.
• C. Keratin is the main component of the dermis making it hard to tear which decreases infections from wounds.

Answer: (A)

Verified step by step guidance

1. Understand that keratin is a fibrous protein found in the outer layer of the skin, hair, and nails, providing structural strength and protection.
2. Recognize that keratin is hydrophobic, meaning it repels water, which helps keep the skin and hair dry. This dryness is crucial because many microbes require moisture to grow and thrive.
3. Consider how the regular shedding of the outer skin layer, which contains keratin, helps remove microbes from the skin's surface, reducing the risk of infection.
4. Acknowledge that keratin contributes to the toughness of the skin, making it more resistant to physical damage and tearing, which can prevent pathogens from entering through wounds.
5. Reflect on how these properties of keratin collectively form a physical and chemical barrier, playing a vital role in the body's innate immune defense against infections.