Body Membranes and Integumentary System Overview

Body Membranes

Cover surfaces, line cavities, protect organs.

Epithelial Membranes

Simple organs with epithelial and connective tissue.

Cutaneous Membrane

Skin; dry membrane, outermost protective layer.

Mucous Membranes

Moist membranes lining cavities open to exterior.

Serous Membranes

Line closed body cavities; consist of two layers.

Visceral Layer

Inner layer of serous membranes covering organs.

Parietal Layer

Outer layer of serous membranes lining cavities.

Peritoneum

Serous membrane in the abdominal cavity.

Pleura

Serous membrane around the lungs.

Pericardium

Serous membrane around the heart.

Synovial Membranes

Connective tissue lining joints and bursae.

Integumentary System

Includes skin and its appendages.

Functions of Integumentary System

Protects from damage, aids in heat regulation.

Epidermis

Outer layer of skin, stratified squamous epithelium.

Dermis

Inner layer of skin, contains dense connective tissue.

Hypodermis

Subcutaneous layer, anchors skin, composed of adipose.

Keratinocytes

Most common epidermal cells producing keratin.

Stratum Basale

Deepest epidermal layer; cells undergo mitosis.

Stratum Spinosum

Layer where cells flatten and keratinize.

Stratum Granulosum

Layer with flattened cells, organelles deteriorating.

Stratum Lucidum

Layer found only in thick, hairless skin.

Stratum Corneum

Outermost layer of dead, keratin-filled cells.

Adipose Tissue

Fat tissue in hypodermis, insulates and cushions.

Serous Fluid

Fluid separating visceral and parietal layers.

Lamina Propria

Loose connective tissue under mucous membranes.

Bursae

Fluid-filled sacs reducing friction in joints.

Eccrine Sweat Glands

Glands producing sweat for thermoregulation.

Sebaceous Glands

Oil glands that lubricate skin and hair.

Stem cells

Cells actively dividing to form new skin layers.

Melanocyte

Cell producing melanin, found in stratum basale.

Melanin

Pigment giving skin color; varies from yellow to black.

Melanosomes

Membrane-bound granules storing melanin pigment.

Epidermal dendritic cells

Immune cells alerting to bacterial or viral threats.

Merkel cells

Touch receptors associated with sensory nerve endings.

Papillary layer

Upper dermal region with dermal papillae projections.

Dermal papillae

Projections indenting epidermis, containing capillary loops.

Reticular layer

Deepest layer of dermis with blood vessels and glands.

Cutaneous sensory receptors

Nerve endings detecting touch, pain, and temperature.

Sebaceous glands

Oil glands producing sebum, keeping skin moist.

Eccrine glands

Sweat glands regulating body temperature via sweat.

Apocrine glands

Sweat glands in armpits and genitals, activated at puberty.

Hair follicle

Structure producing hair, containing root and bulb.

Hair shaft

Visible part of hair projecting from skin.

Keratinized cells

Hard cells forming hair, providing strength.

Hair anatomy

Includes medulla, cortex, and cuticle layers.

Arrector pili muscle

Muscle pulling hair upright in response to cold.

Collagen fibers

Provide strength and structure to the dermis.

Elastic fibers

Allow skin to return to original shape after stretching.

Hemoglobin

Red pigment in blood affecting skin color.

Carotene

Orange-yellow pigment from vegetables influencing skin tone.

Erythema

Redness of skin due to various conditions.

Pallor

Pale skin indicating stress or blood flow issues.

Jaundice

Yellow skin indicating liver dysfunction.

Bruises

Black and blue marks from hematomas.

Nails

Keratinized modifications of the epidermis.

Stratum basale

Layer beneath nail bed responsible for growth.

Nail matrix

Area where nail growth occurs.

Free edge

Distal part of the nail extending beyond fingertip.

Nail folds

Skin folds overlapping nail edges.

Cuticle

Proximal edge of the nail fold.

Athlete's foot

Fungal infection causing itchy, red skin.

Boils

Inflammation of hair follicles, causing pus-filled lumps.

Carbuncles

Clusters of boils caused by bacterial infection.

Cold sores

Blisters caused by human herpesvirus 1.

Contact dermatitis

Skin reaction to chemical exposure causing irritation.

Impetigo

Bacterial infection with fluid-filled lesions.

Psoriasis

Skin condition with red lesions and silvery scales.

Burns

Tissue damage from heat, chemicals, or radiation.

Rule of nines

Estimation method for burn surface area.

First-degree burn

Superficial burn affecting only the epidermis.

Second-degree burn

Burn damaging epidermis and part of dermis.

Third-degree burn

Full-thickness burn destroying epidermis and dermis.

Fourth-degree burn

Burn extending into deeper tissues like bone.

Skin cancer

Most common cancer type, often from UV exposure.

Basal cell carcinoma

Least malignant skin cancer, arises from stratum basale.

Squamous cell carcinoma

Skin cancer from stratum spinosum, induced by UV.

Malignant melanoma

Most deadly skin cancer, arises from melanocytes.

ABCDE rule

Criteria for detecting malignant melanoma characteristics.

Lanugo

Downy hair covering fetus by sixth month.

Vernix caseosa

Oily covering present at birth.

Milia

Small white spots common at birth.

Acne

Skin condition appearing during adolescence.

Skin aging

Loss of elasticity and thinning over time.

Balding

Hair loss influenced by genetics and stress.