Integumentary System

What in the world is integument?

Hint: Integument means covering!

What is in the Integumentary System?

• Skin

• Hair follicles that produce hair

• Nails

• Sweat Glands that produce sweat

• Oil glands

Two Main Layers

• Epidermis

• Top layer, many layers of cells - but only as thick as 2 sheets of notebook paper!

• Most epidermal cells are dead and are filled with keratin to make the skin tough!

• Sensory receptors and melanin are found in epidermis.

Epidermis

Bottom Layer

• Dermis

• Full of nerves for sensory

• Made of tough fibers for toughness

• Has collagen to absorb water and keep the skin hydrated

Dermis

Functions(Good Reasons to have Skin!)

• Protection: Keeps moisture in and foreign particles (bad stuff) out!

• Keeps you “in touch” – nerve endings in the skin allow you to feel what is around you – (senses pain, pressure, hot, cold, and touch)

Two more FunctionsGood Reasons for Skin!

• Regulates body temperature – sweat glands produce salty sweat that flows to surface of skin – As sweat evaporates, the skin cools!

• Gets rid of wastes – Lots of chemicals can leave the body in the sweat!

Hair

• Protects skin from ultraviolet radiation

• Keeps dust and insects out of your nose and eyes

• Gets color from melanin

• Regulates body temperature (Goose bumps are a sweater of hair) They trap the warm air around the body!

Hair

Nails

• Protect the tips of your fingers and toes so they can remain soft and sensitive

• If you have ever cut your nails too short, you know how many nerves are found there!

• The light part at the base of your nail is called the lunula – nails are produced just beneath the lunula

• New cells push older cell toward the edge of your nail

Nails

Skin Color

• Melanin is one of three pigments in the skin that determines skin color

• More melanin the darker the skin

• Melanin absorbs the harmful radiation of the sun

• Carotene is the yellowish pigment

• Hemoglobin in the blood gives the skin its red coloration.

Melanin

Contagious Skin Disorders

• Acne: plugged hair follicles form pimples – Cause is bacteria

Boils

• Boils: Painful infection of hair follicles by a Staph infection

Fever Blisters

• Fever Blisters: Fluid filled blisters

Impetigo

• Impetigo: Highly contagious skin infection caused by bacteria – fluid filled pustules forming yellow crust over infected area

Warts

• Small skin tumors caused by a viral infection that stimulate excessive growth of epithelial cells

Alopecia

• Loss of hair

• Most prevalent in males

• Most inherited

• Can be caused by poor nutrition, drugs, eczema

Eczema

• Inflammation producing redness, itching, scalding and cracking of the skin

• Caused by hyperactivity of the sebaceous glands (oil glands)

Psoriasis

• Chronic dermatitis characterized by reddish raised patches of skin covered with whitish scales

• Result of excessive cell production caused by emotional stress and poor health

Psoriasis

Skin Cancer

• Basal cell carcinoma – 70% treated by removal

• Squamous carcinoma – Treatment consists of radiation and removal

• Malignant melanoma - Most life threatening – starts as a mole, move to other locations – treatment is also radiation and removal

Skin Cancer

Skin Cancer

Malignant Melanoma