Integumentary System

Skin Characteristics• Largest organ• Protects and insulates• Made of keratin (waterproofing)

Skin Functions1) Protects—holds fluids

in, keeps disease causing organisms out

2) Melanin—pigment produced to protect from UV rays

Skin Functions

3) Makes vitamin D from sunlight and a lipid called cholesterol

4) Nerve endings—sense heat, cold, pressure

Skin...working with other systems

• The skin works with:• Immune system—keeps pathogens out•Excretory system—releases waste through sweating•Nervous system—largest sensory organ

Parts of the Skin• Epidermis-top

layer, dead cells with tiny openings called pores• Sebum-an oil,

produced to keep skin soft and flexible

• Dermis-thick layer, made up of collagen and produces melanin•Contains nerve endings, blood vessels, and hair follicles

Parts of the Skin

Parts of the Skin...Oil and Sweat

• The sebaceous and sweat glands also reside in the dermis

Hair and Nails• Hair—made up of dead cells similar

to the top layer of epidermis• Nails—made up of solid plate of

epidermal cells

Pimples/Acne• Caused by a buildup of sebum under

the skin and bacterial infections• Squeezing pimples can cause the

infection to spread/worsen

Keeping Healthy Skin• Clean Skin• Sun protection• Healthy diet

Unhealthy Skin

SunburnBruises

Skin Cancer

Unhealthy Skin

Herpes

Impetigo

Acne

ARCH LOOP WHORL

DOUBLE LOOP

CENTRAL POCKET WHORL

COMPOSITE