 Integumentary System

 Integumentary system: Consists of skin, hair, nails, and glands.  Functions of the Integumentary System  Protection  Sensation  Vitamin D production  Temperature Regulation  Excretion

Regions of Skin  Hypodermis or subcutaneous tissue: Skin sits on top, region that is attached to bone and muscle.  Skin  Dermis: Made up of dense connective tissue  Epidermis: Consists of epithelial tissue that sits on top of the dermis

Skin Structure

Skin Cell Replacement  Keratinization: Is the process where old cells protect new cells below that will eventually replace those old cells.

Random Terms  Stratum Corneum: Is the most superficial strata of epidermis that consists of dead cells. These flake off producing dandruff.  Callus: Skin subject to friction will build up skin layers to prevent damage.

Skin Color  Skin color is determined by pigments in the skin, thickness, and by blood circulating through the skin.  Melanin: Group of pigments responsible for skin, hair, and eye color.  Large amounts of melanin are produced in freckles, moles, genitalia, and nipples  Albinisms: Absence of melanin (White)

Bloods Affect on Skin  Increase Blood Flow = Increase in redness  Blushing, anger, inflammatory response  Decrease in Blood Flow = Decrease in oxygen pale or blue skin  Cold, Shock, Cyanosis in babies

Hair  Hair: Common characteristics to all mammals, it covers most of the body surfaces.  Parts to hair  Shaft- Protrudes above the surface of the skin  Hair Root and Hair Bulb- Are below the surface of the skin  Hair Follicle- Living part of the hair

Muscles  Arrector Pili: Contraction of the arrector pili causes the skin or hair to “stand up”

Glands  Sebaceous Glands: Connected to ducts, and produce sebum an oily, white, lipid rich substance.  Sweat Glands: Produce sweat to help cool the body down.

Jaundice

Nails  Nail: Thin plate, consisting of dead stratum corneum cells.