Chapter 6: Integumentary System Flashcards

A set of vocabulary flashcards covering the anatomy, physiology, layers, and clinical conditions of the Integumentary System based on the Chapter 6 lecture outline.

Integumentary System

A body system composed of a major organ, the skin, and accessory structures such as hair follicles, sebaceous glands, sweat glands, and nails.

Langerhan’s cells

Macrophages that act as a biological barrier and immune response agents against microbes invading the skin; they are easily damaged by UV light.

Tactile (Meissner’s) corpuscles

Sensory receptors found in the upper papillary layer of the dermis that detect light touch.

Lamellated (Pacinian) corpuscles

Sensory receptors found in the reticular layer of the dermis that detect pressure.

Vitamin D Synthesis

A process activated by ultraviolet rays in sunlight, which is required for bone homeostasis.

Epidermis

The outermost layer of the skin, composed of keratinized stratified squamous epithelium.

Dermis

The inner layer of the skin consisting of a papillary layer and a reticular layer; it houses epidermal derivatives, blood vessels, and nervous tissue.

Subcutaneous (hypodermis) layer

A distinct layer of adipose tissue located beneath the skin.

Stratum corneum

The outermost layer of the epidermis, composed of dead epithelial cells filled with the protein keratin.

Stratum lucidum

A translucent layer of cells separating the s. corneum from the s. granulosum; found only in the thick skin of soles and palms.

Stratum basale

The innermost layer of the epidermis, composed of a single row of mitosing cuboidal epithelial cells and melanocytes.

Stratum germinativum

The collective term for the combined layers of the stratum spinosum and stratum basale.

Keratinization

The process of hardening, dehydration, and keratin accumulation that occurs as epidermal cells migrate outward.

Melanocytes

Specialized cells in the stratum basale that produce melanin, a pigment that absorbs harmful UV light.

Merkel cells (Tactile Cells)

Cells that contact sensory neurons to create tactile disks for detecting touch sensations.

Cyanosis

A blue skin tint caused by a lack of hemoglobin ($Hb$) in dermal blood vessels.

Dermal papillae

Finger-like projections of the papillary layer into the epidermis that form fingerprints in thick skin.

Lunula

The region of the nail where active mitosis and epithelium keratinization occur.

Arrector Pili Muscle

A bundle of smooth muscle associated with hair follicles that causes hair to stand on end (goose bumps).

Sebaceous Glands

Holocrine glands associated with hair follicles that secrete sebum (oil) to keep skin and hair soft and waterproof.

Merocrine (Eccrine) Sweat Glands

Glands that respond to elevated temperature and exercise; they secrete a mixture of water, salts, and wastes without creating odor.

Apocrine Sweat Glands

Glands that respond to stress and emotions, begin functioning at puberty, and produce an odorous secretion containing oil and cellular debris.

Radiation

The primary mode of heat loss where infrared heat rays move from a warmer area (blood) to a cooler environment.

Convection

Heat loss to the surrounding air which increases as air movement increases.

Vasodilation

The widening of dermal blood vessels to increase blood flow and heat loss.

Vasoconstriction

The narrowing of dermal blood vessels to decrease blood flow and minimize heat loss.

Hypothermia

A condition characterized by low body temperature, considered very dangerous if the core temperature drops below $94^{\circ}F$.

Superficial partial-thickness burns (1st degree)

Burns affecting only the epidermis, causing reddening and mild pain; usually heals in a few days to $2$ weeks.

Deep partial-thickness burns (2nd degree)

Burns involving both the epidermis and some dermal damage, characterized by reddening and blistering.

Full-thickness burns (3rd degree)

Burns affecting the epidermis, entire dermis, and potentially subcutaneal damage; results in dry, leathery, red or black tissue.

Autograft

A skin transplant taken from an undamaged area of the patient's own body.

Rule of nines

A method used to estimate the body surface area affected by burns to determine treatment and prognosis.