A&P 1 Quiz 2 (Integumentary System

What is the epidermis?

superficial region of skin; multiple layers (thin skin = 4 layers; thick skin = 5 layers); composed of stratified squamous epithelial tissue; keratinized; avascular

Stratum corneum

sloughing, superficial layer; consists of 20-30 layers/rows of densely packed, flat, dead cells (keratinized- filled with keratin, a tough structural protein)

Stratum basale

deep mitotic layer; single layer/row of cube-like cells closest to the basement membrane

Dermis

deeper region of skin; 2 layers; composed of connective tissue- type depends on layer, vascularized

Papillary layer

thin, superficial layer; composed of areolar connective tissue

Dermal papillae

nipple-like projections on superior surface

Reticular layer

thick, deep layer; composed of dense irregular connective tissue

Sweat (sudoriferous) Gland

composed of epithelial tissue; secretory portion-produces sweat; duct-transports sweat

Sebaceous (Oil) Gland

composed of epithelial tissue; secretes oily substance called sebum; always associated with a hair follicle

Hair Follicle

produces hair (pili); hair is composed of keratin

Arrector Pili Muscle

attached to hair follicle; composed of smooth muscle; when contracts, elevates the hair resulting in “goosebumps”

Hypodermis

deep to skin; not actually part of the skin; subcutaneous fat- mostly composed of adipose