(6) Integumentary System

Vitiligo

vitiligo melanocytes are attacked by the immune system & are thus unable to produce melanin which gives pigment to your skin. Vitiligo is not contagious nor life-threatening, but it does often affect the patient's self esteem.

Treatment

• Grafting

• Topical Creams

• PUVA Photochemotherapy

Integument

Largest organ of body

• 16% of body weight

• 1.5-2m² in area

2 parts

• cutaneous membrane (skin)

• accessory structures (hair & skin)

Functions of integumentary system

• Maintains body temp

• excretes sweat

• protects

• synthesizes vitamin D

• stores lipids

• sensory reception

epidermis

Made of avascular (no blood vessels) stratified squamous epithelium, has either 4 or  6 layers.  Thickness of a plastic bag or paper towel.

Where are melanocytes and stem cells?

the stratum basale

melaoncytes

responsible for giving the skin pigment or color, and the melanin they make provides some protection from UV rays

stem cells

continuously dividing, & as the cells age they move up to the superficial surface of the skin.  By the time they get to the stratum corneum (the most superficial layer) they are completely dead. 

keratin

gives skin strength & a degree of waterproofing.  It is found in the epidermis, hair and nails.

fingerprint formation

stratum basale of the epidermis meets the dermis there are papillae which are like ridges

dermis

deep to the epidermis. It contains blood vessels, sweat glands, oil glands, nerves, hair follicles, muscle cells, & lymphatic channels that support & nourish the epidermis.  Additionally it has collagen and elastin to give skin strength & flexibility.

hypodermis

not technically part of the integument, but is important in stabilizing skin and separating it from the muscle layer.  It contains many fat cells which provide insulation, shock absorption, and an energy reserve.

hair

non-living structure mostly made of keratin projecting from most surfaces of the skin.  Not the palms, soles of the feet, or lips.

arrector pili muscle

contract and pull on the follicle, causing the hair to stand up.

Sebaceous gland

exocrine glands that secrete an oil called sebum into hair and skin.  It prevents drying out and is antibacterial.  There is an increase in puberty.

2 sweat glands

apocrine & eccrine

nails

Keratinzed epidermal cells that protect the tips of the fingers and toes

nerves

found in the dermis and there are various types that sense pressure, temperature, pain, light touch and muscle movement.

1.

Epidermis

2.

Dermis

3.

Hypodermis

4.

sweat gland

5.

Hair Shaft

6.

Stratified Squamous Stem Cells

7.

Sebaceous Gland

8.

Arrector Pili Muscle

9.

Nerve

10.

Hair Follicle

11

Subcutaneous Tissue (Fat Cells)