Ch 3 - Integumentary System

Functions of the skin

• protection

• excretion

• stimuli

Epidermis

• outermost layer

• contains keratin, melanocytes (born in basal layer)

• stratified squamous epithelium (block like arrangement of skin cells)

Dermis

• composed of connective tissue

• contains blood/lymphatic vessels, nerve fibers, hair follicles, sebaceous glands, sudoriferous glands

• produces collagen

Hypodermis/subcutaneous

• deepest layer of the skin

• connects skin to muscle

• contains lipocytes (insulation), larger blood vessels, and deeper sweat glands & hair follicles

Cyst

membranous sac/cavity of abnormal character, contains liquid

Macule

small, flat, discolored lesion on the skin

Papule

• solid skin elevation with distinct borders (pimple)

• diameter is less than 1 cm

Pustule

small infected skin elevation that contains puss; abcess

Vesicle

small, raised skin lesion filled with/clear liquid (blister)

Wheal

temporarily raised bump, typically reddened and accompanied by itching

Albinism

inherited condition in which the body lacks melanin

Eczema

acute/chronic inflammatory skin disease (itching and swelling)

Vitiligo

loss of pigment in one or more areas of the skin