SKIN

LAYER OF SKIN

Skin Largest organ ,protect shield of our skin, part of INTIGUMENTARY SYSTEM (Body out layer), ever changing organ, made up of stratified epithelial  cells.

EPIDERMIS LAYER

DERMIS LAYER

SUBDERMIS LAYER

EPIDERMIS LAYER

Top most layer of the skin, it is the outer layer most layer of the skin that we can see, touch and feel. Physical and biological barrier to the external environment. Contents no blood vessels, take nutrition from underlying layer dermis.

CONSIST OF 5 LAYERS  

STRATUM CORNEUM LAYER

STRATUM LUCIDUM LAYER

STRATUM GRANULOSUM LAYER

STRATUM SPINOSUM LAYER

STRATUM GARMINATIVAM LAYER

It varies in thickness thickest of palms of hands and soles feet thickest  on eyelids and lips.

STRATUM CORNEUM LAYER

20 to 30 rows of dead skin cells. It has corneocytes (fish scale like shapes cell). Cells are fully keratinized. Surrounded by fat cells (lipids) that gives waterproofing effect to the skin. It is top most layer of the skin and cells of completely dead.

STRATUM LUCIDUM LAYER

Luci means Transparent. It is a narrow layer, cells are translucent in this layer, light can pass through them. A fixing agent that fixes keratin protein into the cells. Found in palm of hand and soul of feet  abundantly. Cell of completely dead.

STRATUM GRANULOSUM LAYER

Cell look like distinct granules, cells are partly dead. Cells shrink due to lack of nutrition and change their shape into granules. Keratinization begins in this layer process, The prosses of keratin formation where cytoplasm of the cells is replaced by keratin protein.

STRATUM SPINOSUM LAYER

Keratinocytes change their shape into prickles/stones, Since the shape of the cells is spiny/ prickly. this layer is also called PRICKLY LAYER. Also called INTERMIDIATE LAYER. Cell fluid (cytoplasm) is present here cells are alive. provides flexibility and strength.

STRATUM GERMINATIVUM LAYER

Also called as BASAL LAYER, Takes nutrition supply from dermis through basal membrane/ derma epidermal junction. Germinated new cell by mitosis process. 95% of the cells present in this layer are keratinocytes remaining 5% cells are Melanocytes, Marker cells Longer cells   

MELANOCYTES        responsible for color pigment production in the body.

MARKER CELLS       touch receptors.

LONGER CELLS         responsible for immunity.

DERMIS LAYER

It is also called true skin as well the important glands are present in this layer. Inner layer of the skin ,provides flexibility and strength, 75% thicker than epidermis, elastin layer.                                                                                                                                                                Part of dermis 

HAIR FOLLICLE

Visible pore on the skin

HAIR ROOT

Hair grows from hair root

HAIR BULB

Holds the hair together

DERMAL PAPILLA

Supplies nutrients to the hair bulb than to the hair root for hair growth.

ARRECTOR PILLI MUSCLE

Smallest muscle in the body responsible for goose bumps It shrink and attacks hairs to words it self and makes the hair arrect at 90degree.

SEBACEOUS GLAND

Oil glands produces sebum natural oil of the skin makes the skin soft and supple. activity of sebaceous gland determines skin type.

PILLA SEBACEOUS UNIT 

Hair follicle +sebaceous gland+ arrector pills muscle together from pila sebaceous unit.

NERVE ENDING

Also called sensory nerves these are responsible for sensation in the skin.

5 TYPES OF NERVE ENDING ARE PRESENT IN THE SKIN 

PAIN, HEAT, PRESSURE, TOUCH COLD.

SUDORIFEROUS GLAND

Other name sweat glands responsible for detoxification and temperature regulation .

ELASTIN AND COLLAGEN FIBERES

Bundles of fibrous tissues elastin provides elasticity and flexibility to the skin, collagen provides toughness to the skin. The bond of elastin and collagen looses with age that causes ageing of the skin, fine lines, wrinkles. Elastin and collagen in young the skin. Elastin and collagen in mature skin.

BLOOD VESSELS

Supplies nutrient to the skin.

LYMPH VESSELS

Remove wastes and toxins from the body.

SUBDERMIS LAYER

Inner most layer of the skin, Made up of fat cells, adipose tissue. Insulating in nature, gives contouring to the skin, Stores energy in from of fat, varies in thickness.

OTHER NAME

SUBCUTANEOUS LAYER

HYPODERMIS LAYER

FATTY LAYER

SUBCUTE LAYER

ACID MANTLE

Perfect mixture of sebum and sweat, Biological barrier to the skin. Prevents the invasion of bacteria to the skin.