The skin is made up of 3 layers -
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.
- 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.
No comments:
Post a Comment