Receptors in the skin detect various environmental stimuli and respond accordingly, with mechanoreceptors detecting sensations and thermoreceptors detecting heat. These receptors can cause sweat glands to produce sweat, thus maintaining temperature homeostasis as well as getting rid of waste (Denda et al., 2007). Insulation is also provided in the subcutaneous layer of the skin, where fat is stored.
Skin absorbs not only oxygen and water, but also certain drugs, such as topical steroids. In addition, skin is rich in 7 dehydrocholesterol, and when it is exposed to UV light this substance is converted into vitamin D (cholecalciferol), which is otherwise obtained by dietary means, such as by ingesting dairy products
(Chen et al., 2007 ).