The Integumentary System

Integumentary System

• Hair • Skin • Nails

Functions of Integumentary System

• Functions– Protective barrier against infection and injury– Regulates body temperature

• Evaporation of sweat from surface of body cools us off

– Removes waste products• Sweat contains water, electrolytes, and wastes

– Protection from ultraviolet radiation– Sensory Organ

• Pressure• Heat and Cold• Pain

Structure of the Skin• The skin is made of several layers– Epidermis– Dermis– Hypodermis

Structure of the SkinEpidermis

• The epidermis is the top layer of the skin• The epidermis contains 2 layers– Top layer is flattened dead cells– Bottom layer is made of living cells• These cells divide rapidly pushing upward • Cells produce Melanin and Keratin

– Melanin is a protein pigment that helps protect us from sun and gives us our color

– Keratin is a tough fibrous protein that gives skin its strength

Structure of the SkinDermis

• The Dermis is the inner layer of the skin– Lies beneath epidermis

• The dermis contains collagen fibers (elasticity, blood vessels, nerve endings & sensory receptors, smooth muscles, and hair follicles an two types of glands– Sudoriferous glands = sweat glands– Sebaceous glands = oil glands• Makes skin flexible and waterproof

Structure of the SkinHypodermis

• Lies beneath Epidermis and Dermis• Contains Adipose (Fat) and ConnectiveTissues

that help insulate the body and hold the skin in place

Hair

• Hair gives protections from sun and provides insulation from cold

• Hair is produced by tubelike structures called the hair follicles– Hair follicles produce shaft which is filled with keratin and

melanin (strength and color)– Hair follicles are in close contact with sebaceous or oil

glands• Natural conditioner

– Many waste products including drug metabolites are released in hair shaft as well

Nails

• Nails grow from rapidly dividing cells known as the nail root– Keratin producing cells create tough platelike

structure of the nail• Protects nerve ends and sensory receptors in fingertips

• Nails grow at an average of 3mm per months

Skin Cancer

• Skin Cancer is abnormal growth of skin cells • Caused by overexposure to UV radiation from

sunlight– Some People are more likely to get skin cancer • Genetics/skin complexion

• Protect Yourself– Sunblock, hats, self checks, doc checks ect..