Layers of the skin

Epidermis

outermost layer of skin, covers our body, it is thin protective covering with many nerve endings. composed of 5 layers called strata or stratum

Stratum Corneum

(horny layer) top outermost layer of epidermis. very thin layer, waterproof, permeable, regenerates itself, detoxifies the body, responds to stimuli

Stratum Lucidum

thin (clear layer) of dead skin cells under the stratum corner. Layer is translucent made out of small cells that let light pass through; thickest on palms of hands/sole of feet

Stratum Granulosum

(granular layer) composed of cells that resemble granules filled with keratin. production of keratin and intercellular lipids takes place here enzymes

Stratum Spinosum

(spiny layer) cells continue to divide and change shape. here enzymes are creating lipids and proteins. largest layer

Stratum Germinativum

(basal cell layer) located above dermis; composed of a single layer. stem cells undergo continuous cell division in this layer

Langerhans Immune

protect the body from infections by identifying foreign materials is found in here

Keratinocytes

composed of keratin, comprise 95% of epidermis. contain protein and lipids

Keratin

fibrous protein that provides resiliency and protection

Melanocytes

cells that produce pigment granules in basal layer

Melanosomes

pigment carrying granules

Desmosomes

keratin filaments the protein bonds that create junctions between the cell

Corneocytes

waterproof protective cells

What is the average cell turnover rate?

Every 28 days

Dermis

(true skin) support layers of connective tissues above the hypodermis. 25 times thicker than epidermis

Papillary Layer

-connects the dermis to the epidermis

-makes up 10/20% of dermis

Dermal Papillae

membranes of ridges and grooves that attach to the epidermis

Hair Papilla

small cone shaped structures at bottom of hair follicles

Reticular Layer

-denser and deeper layer of the dermis

-mainly collagen and elastin

-damage to elastin fiber= wrinkles and stretch marks

Subcutaneous Tissue

-known as the hypodermis

-composed of loose connective tissue/ sub cutis tissue aka adipose tissue

-80% fat

-gives contour and smooth to body

-provides source of energy for the body

Collagen

protein, substance of complex fiber that gives the skin its strength and is necessary for wound healing. makes up 70% of dermis

Elastin

fibrous protein that forms elastic tissue and gives skin its elasticity

Glycosaminoglycans (GAGs)

large protein molecules found between fiber of dermis

Hyaluronic Acid

hydrating fluids found in skin

Lymph Vessels

remove waste products, bacteria, and excess fluid