Integumentary System Lecture Notes

Comprehensive vocabulary flashcards covering the anatomy, physiology, and pathology of the integumentary system based on lecture notes.

Integumentary System Functions

Protects underlying tissues, detects touch/pain/pressure/temperature, excretes wastes, maintains body temperature, synthesizes Vitamin D, and stores nutrients.

Stratum basale (SB)

Also called Stratum germinativum; the deepest epidermal layer attached to the basement membrane where cells divide by mitosis.

Stratum lucidum (SL)

Layer found in the palms and soles that makes the skin extra thick and appears translucent.

Stratum corneum (SC)

The outermost epidermal layer of flattened, dead cells filled with keratin; it takes $14$ days to travel from SB to SC and $2$ weeks to shed.

Keratinization

Also known as cornification; the process that makes skin impermeable to water and unattractive to bacteria.

Xerosis

A condition characterized by dry skin.

Epidermal ridges

Found where the epidermis meets the dermis, these genetically determined structures increase friction to secure a grip and form fingerprints.

Cyanosis

A blue tint to the skin resulting from a loss of oxygen.

Pallor

A pale skin color caused by decreased blood flow.

Carotene

An orange or yellow skin pigment found in foods.

Melanin

Pigment (yellow, red, brown, black) made by melanocytes in the Stratum basale that protects against UV radiation and folate loss.

Vitamin D Synthesis

Cells in the Stratum spinosum and Stratum basale convert steroid precursors into Vitamin D when exposed to sunlight, which is necessary for calcium absorption.

Papillary layer

The dermal layer composed of areolar tissue containing blood vessels and pain receptors.

Reticular layer

The dermal layer composed of DICT (Dense Irregular Connective Tissue) containing pressure receptors, glands, and hair roots.

Hypodermis

The subcutaneous layer mostly made of adipose tissue that stabilizes skin, provides insulation, energy reserves, and shock absorption.

Arrector pili muscles

Muscles that cause hair to stand up (forming goosebumps) in response to cold or emotional stress.

Sebaceous glands

Exocrine glands that release an oily/waxy secretion (Sebum) into hair follicles; they are activated at puberty.

Sebum

A waxy, oily secretion that provides softness to the skin and inhibits bacterial growth.

Folliculitis

A condition where a sebaceous duct is blocked, resulting in a 'boil' or 'carbuncle' that must be lanced and drained.

Seborrhea

Infected scalp glands characterized by scaly skin, known as 'dandruff' or 'cradle cap' in infants.

Apocrine glands

Sweat glands in the armpits, nipples, and groin that produce a viscous, cloudy secretion that source odors when broken down by bacteria.

Eccrine glands

Also called merocrine glands; numerous glands that secrete a clear, watery substance ($99\%$ water) to cool the skin by evaporation.

Ceruminous glands

Modified sweat glands that secrete cerumen (ear wax) to trap foreign particles and insects.

1st degree burn

A burn characterized by redness (erythema) and mild pain that heals quickly.

2nd degree burn

A burn characterized by blisters and pain that kills cells down to the Stratum basale and into the dermis.

3rd degree burn

A burn that destroys the epidermis and dermis (charred/blanched), leading to loss of sensation, risk of sepsis, and dehydration.

Sepsis

A widespread infection that is a risk factor following a 3rd degree burn.

Rule of 9's

A method used to estimate fluid loss and the critical nature of burns.

Aging effects on Vitamin D

Vitamin D production declines by $75\%$ in the elderly, leading to muscle weakness and decreased bone strength.

Erythema

The medical term for redness, often associated with 1st degree burns.