Other attributes
The skin is the largest organ of the body and is made up of water, proteins, fats and minerals. It has three main layers, the epidermis, the dermis and the subcutaneous layer.
The epidermis is an elastic layer on the outside that is continually being regenerated.
The dermis is the inner layer that includes the following:
Sweat glands – produce sweat that travels via sweat ducts to openings in the epidermis called pores. They play a role in temperature regulation.
Hair follicles – are pits in which hairs grow. Hairs also play a role in temperature regulation.
Sebaceous glands – produce sebum (an oil) to keep hairs free from dust and bacteria. Sebum and sweat make up the 'surface film'.
The subcutaneous layer under the dermis is made up of connective tissue and fat (a good insulator).
Functions of the skin
- Provides a protective barrier against mechanical, thermal and physical injury and hazardous substances.
- Prevents loss of moisture.
- Reduces harmful effects of UV radiation.
- Acts as a sensory organ (touch, detects temperature).
- Helps regulate temperature.
- An immune organ to detect infections etc.
- Production of vitamin D.