Integumentary System

Vocabulary flashcards detailing the anatomical components, layers, and physiological functions of the integumentary system.

Integumentary System

A system comprising the skin, hair, nails, sweat glands, sebaceous (oil) glands, sensory receptors, and arrector pili muscles.

Integumentary System Functions

Protection, temperature regulation, sensation, vitamin D production, prevention of water loss, and excretion of wastes through sweat.

Epidermis

The outermost layer of the skin made of keratinized stratified squamous epithelium; it provides protection and is avascular.

Stratum basale

The deepest epidermal layer where new skin cells are produced through mitosis.

Stratum spinosum

The epidermal layer where cells begin producing keratin and are connected by desmosomes.

Stratum granulosum

The epidermal layer where cells accumulate keratin and begin to die.

Stratum lucidum

A clear epidermal layer found only in thick skin such as the palms and soles.

Stratum corneum

The outermost epidermal layer made of dead, keratinized cells that protect the body.

Dermis

The thick connective tissue layer beneath the epidermis containing blood vessels, nerves, glands, and hair follicles.

Papillary layer

The superficial dermal layer composed of areolar connective tissue containing capillaries and sensory receptors.

Reticular layer

The deeper dermal layer composed of dense irregular connective tissue that provides strength and elasticity.

Hypodermis (subcutaneous layer)

A layer of areolar and adipose tissue beneath the dermis that cushions, insulates, and anchors the skin.

Nerve endings

Sensory receptors in the skin that detect touch, pressure, pain, and temperature.

Sweat glands

Glands that produce sweat to help regulate body temperature and remove wastes; includes eccrine and apocrine types.

Sebaceous (oil) glands

Glands that secrete oily sebum to lubricate and protect the skin and hair; usually associated with hair follicles.

Arrector pili muscle

A small smooth muscle attached to hair follicles that causes goosebumps when contracted.

Hair follicle

A tube-like structure in the skin from which hair grows.

Hair shaft

The visible portion of hair that extends above the skin surface.

Hair root

The portion of hair located below the skin surface within the follicle.

Melanin

A pigment produced by melanocytes that protects against UV radiation and determines skin color.

Vasodilation

The dilation of blood vessels when the body is hot, facilitating cooling through sweat evaporation.

Vasoconstriction

The constriction of blood vessels when the body is cold to reduce heat loss.