Integumentary System Vocabulary

Vocabulary flashcards covering the anatomy, structural layers, appendages, and physiological functions of the integumentary system based on the lecture materials.

Integumentary System

The complex organ system composed of the skin and its derivatives (sweat glands, sebaceous glands, hair, hair follicles, and nails) that provides protective, sensory, thermal, and regulatory functions.

Cutaneous Membrane

The technical name for skin, which functions as an outer covering for the human body.

Epidermis

The outer layer of skin composed of stratified squamous epithelium; it is avascular, predominantly made of keratinocytes, and capable of keratinizing.

Dermis

The underlying skin layer deep to the epidermis composed of dense connective tissue containing collagen, elastic fibers, blood vessels, and sensory receptors.

Hypodermis (Subcutaneous Tissue)

The tissue deep to the dermis, composed mostly of areolar and adipose tissue, which anchors skin to underlying organs, stores fat, and contains pressure-sensing nerve endings.

Keratinocytes

The primary cell type found in the epidermis that produces keratin, making the skin hard and tough to prevent water loss.

Stratum Basale

The deepest epidermal layer containing actively dividing stem cells, melanocytes, and Merkel cells.

Stratum Spinosum

The epidermal layer superficial to the stratum basale, characterized by cells containing thick bundles of intermediate filaments made of pre-keratin.

Stratum Granulosum

The epidermal layer where cells flatten, organelles deteriorate, and cytoplasm becomes filled with granules.

Stratum Corneum

The outermost epidermal layer consisting of flat, dead membranous sacs filled with keratin surrounded by extracellular glycolipids.

Melanin

A yellow to brown to black pigment synthesized by melanocytes in the stratum basale that protects against ultraviolet radiation.

Melanocytes

Specialized pigment-producing cells located mostly in the stratum basale of the epidermis.

Papillary Layer

The upper dermal region containing projections called dermal papillae, capillary loops, pain receptors, touch receptors, and responsible for fingerprints.

Reticular Layer

The deepest layer of the dermis containing blood vessels, sweat glands, sebaceous glands, and deep pressure receptors.

Carotene

An orange-yellow pigment deposited in the skin that is obtained from consuming certain vegetables.

Hemoglobin

The red, oxygen-binding pigment in red blood cells located within dermal capillaries that imparts a reddish hue to skin.

Erythema

Skin redness caused by embarrassment, inflammation, hypertension, fever, or allergic reactions.

Pallor (Blanching)

Unusual paleness of skin caused by emotional stress, fear, anemia, low blood pressure, or impaired blood flow.

Jaundice

A yellow discoloration of the skin indicating an underlying liver disorder.

Hematomas

Bruises caused by blood escaping from circulation and clotting in surrounding tissues under the skin.

Sebaceous Glands

Exocrine oil glands in the skin that produce sebum to lubricate skin, kill bacteria, and prevent hair brittleness.

Sebum

An oily substance secreted by sebaceous glands that acts as a lubricant and antibacterial agent.

Blackheads

Skin lesions that form when sebaceous gland ducts become blocked.

Eccrine Sweat Glands

Abundant sudoriferous glands that empty clear sweat directly onto the skin surface via pores to assist in body heat dissipation.

Apocrine Sweat Glands

Sudoriferous glands activated at puberty that empty into hair follicles, producing a milky or yellowish secretion containing fatty acids and proteins.

Arrector Pili Muscle

Smooth muscle bundles attached to hair follicles that contract to pull hair upright when cold or frightened.

Hair Shaft Concentric Layers

The three structural regions of a hair strand: the central medulla, middle cortex, and outermost cuticle.

Hair Cuticle

The outermost, heavily keratinized layer of a hair shaft consisting of scale-like overlapping cells.

Split Ends

Hair damage caused when the protective overlapping cuticle wears away at the tip of the hair shaft.

Nail Matrix

The thickened proximal portion of the stratum basale beneath the nail bed responsible for nail growth.