Anatomy test chapter 4 yay

Contact dermatitis

Skin inflammation marked by itching, redness, and swelling caused by direct exposure to allergic chemicals.

Melanocyte

Specialized cell predominantly located in the stratum basale that synthesizes protective melanin pigment.

Stratum corneum

The most superficial epidermal layer consisting of flattened, dead keratinized cells that safeguard against water loss.

Stratum basale

The deepest epidermal layer bordering the dermis where stem cells actively undergo mitosis to regenerate the epidermis.

Keratinocyte

The predominant cell type in the epidermis that synthesizes fibrous structural protein and links to adjacent cells via desmosomes.

Impetigo

A highly contagious bacterial skin infection presenting with pink, fluid-filled crusted lesions around the nose and mouth.

Cold sores

Itching, stinging, fluid-filled fever blisters around the mouth caused by human herpesvirus 1.

Psoriasis

A chronic autoimmune skin condition characterized by red epidermal patches covered with dry, silvery scales.

Keratin

A tough, fibrous protein that renders the outer epidermis, hair, and nails durable and water-resistant.

Sebum

An oily lipid mixture produced by cutaneous glands that lubricates skin, prevents hair brittleness, and inhibits bacterial growth.

Eccrine sweat gland

Abundant, coiled tubular cutaneous gland that secretes clear, acidic perspiration directly onto the skin surface for thermoregulation.

Apocrine sweat gland

Sweat gland localized to the axillary and genital regions that activates during puberty and empties secretions rich in fatty acids into hair follicles.

Sebaceous gland

Exocrine gland distributed over the entire body except palms and soles that typically empties sebum into hair follicles.

Cutaneous membrane

A dry external body membrane consisting of keratinized stratified squamous epithelium anchored to dense irregular connective tissue.

Mucous membrane (mucosa)

A moist epithelial membrane lining internal cavities that open directly to the exterior, specialized for absorption or secretion.

Serous membrane (serosa)

A paired simple squamous and areolar membrane lining closed ventral body cavities, separated by friction-reducing lubricating fluid.

Parietal layer vs. visceral layer of serosa

The parietal layer lines the outer cavity wall, while the visceral layer folds inward to cover the exterior surface of the enclosed organ.

Peritoneum

The serous membrane enclosing the abdominal cavity and enveloping its viscera.

Pleura

The double-layered serous membrane encasing the lungs and lining the thoracic pleural space.

Pericardium

The serous membrane envelope that surrounds and cushions the heart.

Synovial membrane

A connective tissue membrane composed solely of areolar tissue without epithelium, lining joint capsules, bursae, and tendon sheaths.

Epidermis vascularity and tissue composition

Avascular keratinized stratified squamous epithelium that receives nourishment exclusively via diffusion from the underlying dermis.

Dermis vascularity and tissue composition

A highly vascularized connective tissue layer divided into a superficial areolar papillary layer and a deeper dense irregular reticular layer.

Hypodermis (subcutaneous tissue)

The adipose-rich layer deep to the dermis that anchors skin to underlying muscle, absorbs shocks, and insulates against heat loss.

Papillary layer of dermis

The upper dermal zone featuring dermal papillae, capillary loops, pain receptors, and touch receptors that form fingerprint ridges.

Reticular layer of dermis

The deepest dermal region composed of dense irregular connective tissue, rich in blood vessels, nerves, glands, and deep pressure receptors.

Epidermal layers (deepest to most superficial)

Stratum basale, stratum spinosum, stratum granulosum, stratum lucidum (thick skin only), and stratum corneum.

Stratum lucidum

A thin, translucent band of dead keratinocytes found exclusively in the hairless, thick skin of palms and soles.

Carotene

An orange-yellow lipid-soluble pigment ingested through vegetables that deposits in the stratum corneum and subcutaneous fat.

Hemoglobin contribution to skin color

Oxygen-carrying blood protein within dermal capillary beds that lends a rosy or red tint to fair complexion.

Erythema

Reddening of the skin caused by dilated dermal capillaries due to blushing, fever, hypertension, allergy, or inflammation.

Cyanosis

A bluish tint of the skin and nail beds indicating insufficient oxygenation of circulating hemoglobin.

Jaundice

A yellow discoloration of the skin and eyes caused by abnormal accumulation of bile pigment (bilirubin) from liver malfunction.

Pallor

Blanching or pale skin appearance triggered by reduced blood flow, emotional fright, anemia, or low blood pressure.

Bruising (hematoma)

Black-and-blue discoloration caused by blood escaping from damaged dermal vessels and clotting in tissue spaces.

Arrector pili muscle

Smooth muscle bands connected to hair follicles that contract when cold or frightened, pulling the hair upright and causing goosebumps.

Concentric layers of a hair (center outward)

The central core (medulla), the surrounding cortex, and the heavily keratinized outermost cuticle.

Basal cell carcinoma

The least malignant and most prevalent skin malignancy, arising from the deepest epidermal stratum as shiny, dome-shaped nodules.

Squamous cell carcinoma

Skin cancer originating in the stratum spinosum that presents as scaly, reddened ulcers and can metastasize to regional lymph nodes.

Malignant melanoma

The deadliest form of skin cancer, arising from pigment cells and capable of rapid metastasis to lymph nodes and blood vessels.

ABCDE rule of melanoma

Clinical diagnostic guide: Asymmetry, Border irregularity, Color variation, Diameter greater than 6 mm, and Evolution/change.

First-degree burn

Partial-thickness burn damaging only the epidermis, characterized by localized redness, swelling, and pain without blistering.

Second-degree burn

Burn involving the entire epidermis and superficial dermis, characterized by pain, erythema, and blister formation.

Third-degree burn

Full-thickness burn destroying the entire epidermis and dermis; nerve endings are destroyed leaving the area painless, requiring skin grafts.

Fourth-degree burn

Deep, severe burn extending into underlying muscle, tendons, and bone, requiring surgical intervention, grafting, or amputation.

Rule of nines

A standardized clinical method dividing adult body surface area into multiples of 9% to estimate burn extent and fluid replacement needs.

Two primary causes of death in severe burn victims

Massive fluid and electrolyte loss leading to circulatory shock in the acute stage, followed by severe bacterial infection/sepsis.

Integumentary response to high temperature

Hypothalamic activation stimulates eccrine sweat gland secretion and dermal blood vessel dilation to radiate heat.

Integumentary response to low temperature

Dermal capillary beds constrict to divert warm blood toward vital core organs while arrector pili muscles contract.