The skin is made up of 3 layers -
1. Epidermis
3. Subcutaneous Tissue
- epidermis,
- dermis, and
- subcutaneous tissue
1. Epidermis
The
epidermis is the outer layer and acts as a barrier to the external
environment. The thickness of the epidermis varies in different types of
skin. The epidermis contains 5 layers. The top layer of the epidermis,
the stratum corneum, is made of dead, flat skin cells that shed about
every 2 weeks. The melanocyte produces pigment (melanin) is in the
epidermis.
2. Dermis
The dermis also varies in thickness depending on the location of the skin. The dermis is composed of 3 types of tissue:
1. Collagen
2. Elastic tissue and
3. Reticular fibers
The 2 layers of the dermis are:
1. The papillary layer (upper layer): contains a thin arrangement of collagen fibers.
2.
The reticular layer (lower layer): is thicker and made of thick
collagen fibers that are arranged parallel to the surface of the
skin.
The
dermis contains hair follicles, sebaceous (oil) glands and apocrine
(scent) glands, sweat glands, blood vessels, nerves (The nerves transmit
sensations of pain, itch, and temperature) and specialized nerve
cells (that transmit the sensations of touch and pressure).
3. Subcutaneous Tissue
The
subcutaneous tissue is a layer of fat and connective tissue that
contains larger blood vessels and nerves. This layer is important in the
regulation of skin's and body's temperature. The size of this layer
varies throughout the body and from person to person.