Anatomy chp 6 cont Hair and nails

Hair: Guards the head-from sunburn and injury from a glancing blow Protects the eye Keeps foreign materials out of the airways

Hair structure: Follicle-epithelial cells Root-enclosed by the follicle Shaft-projects from the skin Matrix-growth zone in the follicle Arrector pilli-muscle for hair movement

Structure of a hair: Medulla-inner layer Cortex-middle layer Cuticle-outer layer

Nails: Modified epidermis

Nail structures: Free edge Body Root Cuticle-thick proximal nail fold Nail matrix-growth zone of the nail Lunula-white crescent area of nail

Skin infections and allergies: Athlete’s foot-fungal infections Boils-inflamed hair follicle Cold sore-fluid filled blister form herpes virus or stress Impetigo-very contagious staphylococcus bacteria; reddish pink lesions around mouth and nose

Burns: May kill due to High fluid loss Infection

Degrees of burns: 1st degree-epidermis is damaged-sunburn, stove or oil; regeneration will occur-painful 2nd degree-epidermis and upper regions of dermis is damaged-skin blisters; regeneration will occur-very painful 3rd degree-destroys entire thickness of the skin, nerve endings are destroyed so the burn area is not painful; no regrowth or regeneration-must have skin graff

Cancer: Own cells growing uncontrollable-forms a mass that can shut systems down??????

Skin cancer: Cancer gene is thought to be turned on by ultra violet light-radiation or some unknown reason???????????

Cancer terms: Benign tumor-non cancerous Malignant tumor-cancerous Carcinoma-slow growing cell mutation Melanoma-spreading brown or black patch from moles

ABCD rules for moles: A-Asymmetry-matching sides B-Border-irregularity-not having smooth borders C-Color-many pigments-brown, black and red D-Diameter-increasing in size or height-anything larger than 6mm(pencil eraser) should be checked