You have three main layers of skintheepidermis,dermis,andhypodermis(subcutaneous tissue).
Within these layers are additional layers.
If you count the layers within the layers, the skin has eight or even 10 layers.
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Skin is the largest organ in the body and is quite complex.
Its primary function is to act as a barrier against disease-causingpathogens(germs) and hostile environments.
It also helps regulate body temperature and gathers sensory information from your environment.
Verywell / Alexandra Gordon
This article looks at the three main layers of skin and the layers within them.
The Epidermis
The epidermis is the outermost skin layer.
Its thickness depends on where it is on the body.
Conditions and disorders that affect the epidermis include:
It is made up of the following five layers.
Stratum Corneum
Thestratum corneumis the top layer of the epidermis.
Keratinocytes produce keratin, a fibrous protein that helps provide structure to your skin, hair, and nails.
In thinner areas, its cells and functions are incorporated into other layers.
The stratum lucidum:
This layer is also made of dead, flattened keratinocytes.
The name comes from it appearing clear or “lucid” when examined microscopically.
Stratum Granulosum
Thestratum granulosumlayer contains keratinocytes that are gradually being pushed toward the surface of the skin.
Stratum Spinosum
Thestratum spinosum, orsquamouscell layer, is the thickest part of the epidermis.
Stratum Basale
Also called the basal cell layer, thestratum basaleis the bottom layer of the epidermis.
It contains connective tissue, capillaries, nerve endings, andhair follicles.
Conditions and disorders that affect the dermis layer include:
The dermis is split into two parts.
Papillary Dermis
Thepapillarydermis is the thin upper layer directly beneath the epidermis.
The junction of the two is called the dermoepidermal junction (DEJ).
It contains capillaries (tiny blood vessels) that help regulate skin temperature and provide nutrients to the epidermis.
Collagen is the main protein that provides structure to skin and connective tissues.
It gives skin elasticity and strength.
The thickness of the dermis varies by its location on the body.
On the eyelids, it is roughly 0.6 millimeters thick.
On the back, palms of hands, and soles of the feet, it’s 3 millimeters thick.
Hypodermis
The innermost layer of the skin is the hypodermis.
It insulates you against changing temperatures and protects your muscles and internal organs from impacts and falls.
In medical shorthand, subcutaneous is abbreviated SQ.
An SQ injection is delivered to the subcutaneous layer.
It is made of three layers, each of which has specific functions.
The middle dermis is responsible for supporting and strengthening the skin.
It helps keep the skin moisturized and nourishes the epidermis.
It also aids with fine sensations and helps regulate the skin temperature.
The innermost subcutaneous tissue insulates the body against changes in temperature and physical impacts.
It gives the body its contoured shape and connects the skin to the internal organs.
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