integumentary system

skin

largest organ of the body and main component of the integumentary system

skin, hair, nails, glands

four main components of the integumentary system

sebaceous, sweat, mammary

three main types of skin glands

protection

skin function that shields against UV, pathogens, and injury

thermoregulation

skin function that regulates body temperature via sweat and blood flow

sensation

skin function involving touch, pressure, pain, and temperature detection

metabolic function

skin function that produces Vitamin D after UV exposure

excretion

removal of salts, water, and waste via sweat

langerhans cells

immune defense cells in the epidermis

epidermis

outer avascular layer of skin made of keratinized epithelium

dermis

layer of skin with loose & dense connective tissue, contains glands and hair follicles

hypodermis (subcutaneous layer)

deepest skin layer containing adipose for insulation and cushioning

stratum basale

deepest epidermal layer where mitosis occurs

stratum granulosum

epidermal layer with keratohyalin granules and waterproofing lipids

stratum lucidum

clear epidermal layer found only in thick skin

stratum cornium

outermost epidermal layer of dead, keratinized cells

keratinocytes

main epidermal cells producing keratin

melanocytes

pigment-producing cells that protect DNA from UV

merkel cells

touch receptor cells in the epidermis

langerhans cells

immune cells in the epidermis that detect pathogens

anagen, catogen, telogen

cycles of hair growth in order

nails

structure covering fingertips and toes for protection and grip

sebaceous glands

gland that secretes sebum for lubrication

eccrine gland

sweat gland for cooling, widely distributed

apocrine gland

sweat gland in armpits/groin, produces thick secretion

ceruminous gland

modified apocrine gland in the ear canal

mammary gland

specialized gland for milk secretion

melanin

pigment responsible for UV protection

carotene

pigment from diet that gives yellow-orange tone

hemoglobin

protein in blood giving pink/red hue to skin

hemostasis inflammation proliferation remodeling

four stages of wound healing

first degree burn

burn that affects only epidermis

second degree burn

burn that affects epidermis and part of dermis

third degree burn

burn that destroys full thickness of skin

basal cell carcinoma

most common but least malignant skin cancer

melanoma

deadliest type of skin cancer

thinner epidermis, reduced collagen/elastin

two main structural changes in skin with aging

decreased melanocyte activity

reason older skin appears paler and more UV-sensitive