The Integumentary System Flashcards

A complete set of vocabulary flashcards covering the systems, layers, cells, glands, and pathologies of the integumentary system based on the lecture study guide.

Integumentary system

Skin and its accessory structures.

Cutaneous membrane

The skin.

Epidermis

Superficial epithelial layer of skin composed of keratinized stratified squamous epithelium.

Dermis

Deeper connective tissue layer of skin containing blood vessels, glands, sensory receptors, and hair follicles.

Hypodermis

Subcutaneous layer below the skin; mostly areolar and adipose tissue. It is not technically part of the cutaneous membrane.

Skin weight percentage

The skin accounts for about $10\text{--}15\%$ of body weight.

Keratinocyte

Main epidermal cell; produces keratin.

Melanocyte

Cell that produces melanin for UV protection.

Dendritic (Langerhans) cell

Immune cell in the epidermis.

Merkel cell

Touch-sensitive cell in stratum basale.

Melanin

Pigment that helps protect against UV damage and shields DNA; produced from tyrosine with the help of tyrosinase.

Melanosome

Vesicle in which melanin is made/stored and then transferred to keratinocytes.

Tyrosinase

Enzyme involved in melanin production.

Stratum basale

Deepest epidermal layer where mitosis occurs and stem cells divide; contains melanocytes and Merkel cells.

Stratum spinosum

Epidermal layer with a spiny appearance due to desmosomes; contains dendritic cells.

Stratum granulosum

Layer where keratinization and waterproofing increase; cells flatten and begin to die.

Stratum lucidum

Clear epidermal layer found only in thick skin (palms and soles).

Stratum corneum

Outermost layer of dead keratinized cells that protect against abrasion and water loss.

Papillary layer

Superficial dermis composed of areolar connective tissue.

Reticular layer

Deeper dermis composed of dense irregular connective tissue.

Eccrine gland

Common sweat gland for cooling; produces watery sweat.

Apocrine gland

Sweat gland in axilla and anogenital regions; produces a thicker secretion.

Ceruminous gland

Modified sweat gland that makes earwax.

Mammary gland

Modified sweat gland that produces milk.

Sebaceous gland

Oil gland that secretes sebum by holocrine secretion; not present on palms and soles.

Sebum

Oily secretion that lubricates skin and hair.

Arrector pili

Smooth muscle attached to a hair follicle.

Erythema

Redness of the skin.

Rule of nines

Method to estimate burned body surface area.

First-degree burn

Affects only the epidermis and causes redness and pain.

Second-degree burn

Affects the epidermis and part of the dermis and commonly forms blisters.

Third-degree burn

Full-thickness burns that may initially be painless due to nerve destruction.

Basal cell carcinoma

Most common and least dangerous skin cancer; least likely to metastasize.

Squamous cell carcinoma

Cancer of keratinocytes that can spread; arises from the stratum spinosum.

Melanoma

Most dangerous cancer of melanocytes.

ABCDE warning signs

Asymmetry, Border irregularity, Color variation, Diameter, Evolving; used to recognize melanoma.