The skin is the largest and most complex organ of the human body. Just as the heart is an organ that pumps the blood around the body, the skin is an organ that performs many essential functions that are vital to life.
Most importantly the skin helps to regulate your body’s temperature and helps to maintain your internal balance. The skin also provides a protective barrier keeping harmful substances out and water and body parts in.
There are two basic parts to the skin. The outermost surface of the skin is called the epidermis. This acts as a barrier and prevents water from being lost from the body. The dermis or the inner, thicker layer of living tissue is made up of tough proteins that help nourish the dermis.
The Epidermis is the top layer of skin, which we take off when we skin our knee. The epidermis is made up of several cell layers, hair, nails and melanin. Melanin is the pigment in the skin responsible for our skin colour. The freckles that appear on the skin of lighter races are also caused by melanin.
The deeper layers of the epidermis contain nerves, but there are no blood vessels in the epidermis. To draw blood from a cut, the cut must go deep enough to reach the dermis.
The most plentiful cells in the epidermis are called Keratinocytes, and these manufacture a tough fibrous protein that is present in our hair and nails. These cells are continually dividing and moving up towards the skins’ surface where they die and shed in the form of scales.
As the scales are shed on the surface of the skin, new cells are formed in the deepest layer of the epidermis. The new cells eventually make their way to the surface and are easily rubbed off when drying yourself with a towel…and on goes the process.
The Dermis, which is the layer of skin below the epidermis, is made up of a closely woven network of connective tissue. It contains blood vessels, vessels for carrying lymph, nerves, glands and hair follicles. The dermis is thickest on your back and thinnest on your eyelids.
The dermis is attached to the epidermis by tiny projections called papillae. These are rich in capillaries and nerves, and thus allow us to react quickly to sensations such as pain, touch, warmth etc. These nerves are especially well developed on the inside of the hand.
The skin performs a variety of functions, with the most important ones being the protection of the body and it’s ability to help maintain the body’s internal balance. The sweat and sebaceous glands in the dermis of the skin are what helps to keep the body in balance.
The sweat glands main function is to regulate body heat, and there are over two million of these spread over the body. They are most abundant on the palms of the hands and soles of the feet and the forehead. The sweat glands also give off small amounts of liquid waste matter.
The sebaceous glands generally open into the hair follicles and discharge an oily substance, which makes the hair smooth and shiny. The oil also keeps the skin moist.
The most important care that can be given to the skin is to keep it clean. This will prevent the tiny pores in the skin from becoming clogged. It will also hinder the spread of infections on the skin and help to minimise inflammation.