Chapter 4: The Integumentary System - Vocabulary Flashcards

Vocabulary flashcards covering key terms from the lecture notes on the integumentary system.

Integumentary system

The skin and its accessory structures (hair, nails, sweat and oil glands, and mammary glands) that protect the body and regulate temperature.

Integument

Another term for the skin; the outer protective layer of the body.

Epidermis

The outermost layer of skin; a stratified squamous epithelium.

Dermis

The deeper, connective tissue layer of skin that supports the epidermis.

Subcutaneous layer (hypodermis)

Layer deep to the dermis; primarily adipose tissue and connective tissue; not part of the skin proper.

Accessory structures

Hair, nails, and multicellular exocrine glands associated with the skin.

Keratinocytes

The most abundant epidermal cells that produce keratin.

Melanocytes

Pigment-producing cells in the epidermis that synthesize melanin.

Merkel cells

Sensory cells in the epidermis involved in tactile sensation.

Langerhans cells

Fixed macrophages in the epidermis that function in immune defense.

Stratum germinativum (basal layer)

Innermost epidermal layer where stem cells reside; attached to the basal lamina.

Stratum spinosum

Layer of keratinocytes bound by desmosomes; some cells may still divide.

Stratum granulosum

Layer where keratinocytes synthesize keratohyalin and keratin.

Stratum lucidum

Clear, glassy layer found only in thick skin.

Stratum corneum

Outermost layer of dead, flattened keratinocytes; provides protection and water resistance.

Thick skin

Skin with a visible stratum lucidum, found on palms and soles.

Thin skin

Skin lacking a distinct stratum lucidum; covers most of the body.

Epidermal ridges

Ridges in thick skin that form fingerprints.

Basal lamina

Thin extracellular layer that anchors the epidermis to the dermis.

Melanin

Pigment produced by melanocytes; determines skin color and protects against UV radiation.

Melanosome

Organelle within melanocytes that transports melanin to keratinocytes.

Keratin

Protein in skin, hair, and nails that provides strength and protection.

Keratinization

Process by which keratinocytes become filled with keratin and die as they move toward the surface.

Hair follicles

Structures that produce hair; extend into the dermis.

Hair

A nonliving, keratinized filament that extends above the skin surface; most hairs are not on the head.

Arrector pili muscle

Smooth muscle that raises hair when contracted."

Hair shaft

Part of the hair that extends above the skin surface."

Hair root

Part of the hair located below the skin surface within the hair follicle."

Cortex (hair)

Layer of hair surrounding the medulla; provides strength and color."

Medulla (hair)

Central core of the hair shaft."

Cuticle (hair)

Outermost layer of hair composed of overlapping keratinized cells."},{