What is an epidermis?

Epidermis forms the outer layer of the skin and creates a hard, renewable waterproof barrier against the environment. It is a type of epithelium, tissue that forms surfaces and lining in the body. On most of the body, the epidermis is relatively thin, while in areas such as hands and foot feet, it is much stronger and hairless. Depending on its location, the epidermis may contain hair follicles, nails and sweat and sebaceous glands. The skin study is known as dermatology.

with its multiple layers of epithelial cells protect the epidermis body from the world outside. The main type of cell it contains is keratinocyte, so -called because it produces hard proteins called keratins that help strengthen the skin. Like the hard, the epidermis must be constantly renewed and repaired any damage caused by injury. It makes it constantly growing new layers of cells.

The deepest layer of cells is known as a basal layer. Basal cells are divided to form new keratinocytes and how each following layer is formed,The layer above is pushed closer to the skin surface. The closer cells are to the surface, the flatter they become as long as the layers of the outer layers consist of what is called a spinocellular epithelium. This is made of flat dead keratinocytes known as squames.

While these cells on the surface are dead and constantly shed, keratinocyte layers lower are still alive and active. What is called the granular cell layer seal from living cells and creates a waterproof barrier. This means that although water can cause surface skin cells to swell when bathing, it does not have to penetrate the deeper epidermal layers. The presence of a layer of granulated cells also prevents unregulated water loss from the body.

In addition to keratinocytes, there are many other cells in the epidese. Melanocytes are partly responsible for the color of the skin through the production of pigment melanin. Merkel cells are associated with the sensing worldLangerhans are part of the body's immune response.

sweat glands are present in the epidermis and are important in regulating the body temperature by allowing sweat to evaporate from its surface. Together there are hair follicles and sebaceous glands, while the glands produce oil to help prevent skin drying. After injury, including extensive removal of the epidermis, the body can use any epithelial cells that remain behind in slightly deeper sweat glands and hair follicles.