4.3 - Functions of the Integumentary System
The skin is the largest organ
in the human body by mass, and is important in homeostasis
and the protection
of deeper tissues
Homeostatic functions of the skin
- Glycolipids and keratin in the upper layers of skin prevent the skin from drying out and prevent water loss from the body as a whole.
Vitamin D synthesis
Protective functions of the skin
- Nitrogenous wastes (urea and uric acid) are excreted by the sweat glands
Several skin structures
are responsible for physical
- Melanin in keratinized cells near the surface of the skin helps block ultraviolet radiation from damaging delicate underlying structures.
- When undamaged, the integument is a continuous surface preventing the entry of bacteria into the body. Acidic sebum produced by eccrine sweat glands helps to inhibit bacterial growth. If pathogens enter the dermis, resident phagocytes engulf and destroy foreign substances before they can invade deeper tissues.