Integumentary System: Skin Layers and Functions

These flashcards cover key vocabulary terms and concepts related to the integumentary system, specifically the structure and function of the skin and its layers.

Integumentary System

The system that includes the skin and its accessory structures, such as hair, nails, sweat glands, and sebaceous glands.

Epidermis

The outermost layer of skin, composed mainly of epithelial tissue, and is avascular.

Dermis

The layer of skin beneath the epidermis, consisting of connective tissue, blood vessels, and nerves.

Hypodermis

Also known as the subcutaneous layer, this layer lies beneath the dermis and is primarily composed of adipose tissue.

Keratinocytes

The primary cell type in the epidermis that produces keratin, providing waterproofing and protection.

Melanocytes

Cells located in the stratum basale of the epidermis that produce melanin, a pigment that gives skin its color.

Stratum Basale

The deepest layer of the epidermis, where cell division (mitosis) occurs, containing living keratinocytes, melanocytes, and Merkel cells.

Stratum Spinosum

The layer of the epidermis above the stratum basale, characterized by spiny keratinocytes and the presence of Langerhans cells.

Stratum Granulosum

The layer of the epidermis where keratinocytes begin to die and accumulate keratohyalin granules, contributing to the skin's water resistance.

Stratum Lucidum

A thin, clear layer of dead keratinocytes found only in thick skin, such as the palms and soles of the feet.

Stratum Corneum

The outermost layer of the epidermis, consisting of 20 to 30 rows of dead, keratinized cells that protect underlying layers.

Dermal Papillae

Small, nipple-like projections of the dermis that push into the epidermis and contribute to fingerprint patterns.

Meissner's Corpuscles

Sensory receptors located in the dermal papillae responsible for detecting light touch and texture.

Pacinian Corpuscles

Sensory receptors located deeper in the dermis that respond to deep pressure and vibration.

Ruffini Corpuscles

Sensory receptors in the reticular layer of the dermis that detect pressure, stretching, and vibration.

Sebaceous Glands

Glands in the skin that secrete oil (sebum) to lubricate and waterproof the skin and hair.

Sweat Glands

Glands that produce sweat to help regulate body temperature and excrete waste.

Avascular

A term describing tissues that lack blood vessels; the epidermis is avascular.

Desmosomes

Structures in the skin that anchor cells together, providing strength against abrasion.

Adipocytes

Fat cells found in the hypodermis that are responsible for nutrient storage and insulation.