Integumentary System Notes

Protective covering from infection

Skin function 1/7

Regulates body temperature

Skin function 2/7

Makes Vitamin D

Skin function 3/7

Provides senses; touch

Skin function 4/7

Temporary stores fat, glucose, water, salts

Skin function 5/7

Screens out harmful UV rays

Skin function 6/7

Absorbs certain drugs and substances well; topical

Skin function 7/7

Epidermis

[SKIN LAYERS] Outermost covering, made of epithelial cells, avascular

Dermis

[SKIN LAYERS] True skin, connective tissue, vascular

Hypodermis

[SKIN LAYERS] Subcutaneous layer (“below the skin”), fatty tissue (stores fat & anchors skin), different patterns of accumulation (male/female)

stratum basale/germinativum

[EPIDERMIS] innermost layer; single row of cells attached to the dermis; youngest cells

Stratum spinosum

[EPIDERMIS] resist tension

Stratum granulosum

[EPIDERMIS] LAYERS of flattened keratinocytes that produce keratin (hair and nails also made of it)

Stratum lucidum

[EPIDERMIS] layer present only on palms, feet, and sores

Stratum corneum

[EPIDERMIS] cells dead, many layers thick

Outermost layer, waterproof, flat and scale-like cells that flake off, first line of defense against surface bacteria, thickets on palms and soles

List traits of Srtatus CORNEUM

Innermost epidermal layer, reproductive layer, contains melanocytes

List traits of Stratus BASALE/GERMINATIVUM

black, brown, yellow

Skin can have a _____, ______, or _____ tint, depending on a person’s racial origin.

melanin

The more _____, the darker their skin.

Caucasians

______ don’t have as much melanin in their melanocytes.

Freckles

Patches of melanin on the skin

Albinism

rare condition when a person has no melanin in their melanocytes

Melanism

rare condition when someone has an abnormally high amount of melanin in their melanocytes

Sunlight

_______ stimulates melanocytes to make more melanin.

UV rays

Tanning is produced by _______

skin cancer

Prolonged to UV rays exposure may lead to ________.

dermal papillae

Ridges in stratum basale/germinativum that arise from dermis

permanent ridges

Papillae creates ___________ in fingers, palms, and soles of feet

grip

The ridges of the papillae help with _____.

fingerprints

Papillae causes ridges called ______.

Loops (65%), Whorls (30%), Arches (5%)

List the three patterns of fingers and how common they are.

Dermis

thick inner layer containing connective tissue, blood pressure, nerve endings, muscles, hair follicles, fat cells, and oil/sweat glands

Sensory nerves (temp & pain), touch receptors (texture, close to surface), pressure receptors (located deeper)

List the three nerve receptors in the dermis

Hypodermis/Subcutaneos layer

Lies under dermis, made up of loose connective tissue, contains half of the body’s fat.