Skin & Body Membranes Flashcards
Cutaneous membrane
- Epithelial membrane
- Location: skin, outermost protective boundary
- Epidermis: keratinized stratified squamous epithelium
- Dermis: dense connective tissue
Mucous membrane
- Epithelial membrane
- Location: body cavities that open to exterior
- Stratified squamous epithelium (mouth, esophagus)
- Simple columnar epithelium (rest of digestive system)
- Underlying loose connective tissue, lamina propria
- Absorption, secretion
Serous membrane
- Epithelial membrane
- Location: open body cavities closed to exterior
- Surface: simple squamous epithelium
- Underneath: areolar connective tissue
- Visceral layer (outside of organ) paired with parietal layer (lines portion of ventral body cavity), separated by serious fluid
- Ex. peritoneum (abdominal cavity), pleura (around lungs), pericardium (around heart)
Synovial membrane
- Connective membrane
- Location: fibrous capsules surrounding joints
- Made of connective tissue only
- Secretes a lubricating fluid
Skin protects tissues from…
- Mechanical damage
- Chemical damage
- Bacterial damage
- UV radiation
- Thermal damage
- Drying out
Layers of epidermis (deep to superficial)
Stratum basale Stratum spinosum Stratum granulosum Stratum ludicum (hands + feet) Stratum corneum
Factors that determine skin color
Melanin (can be yellow, brown, black)
Carotene (orange-yellow pigment produced by some vegetables)
Hemoglobin (red coloring from blood cells in dermal capillaries, brighter red = more oxygen)
Basal cell carcinoma
- Least malignant
- Most common
- Arises from stratum basale
Squamous cell carcinoma
- Early removal allows good chance of cure
- Believed to be sun-induced
- Can spread to lymph nodes if not removed
- Arises from stratum spinosum
Malignant melanoma
- Most deadly
- Metastasizes rapidly to lymph and blood vessels
- Arises from melanocytes
First-degree burn
- Skin is pink or red but no blistering
- Only epidermis is damaged
Second-degree burn
- Blistering
- Injury to epidermis and upper region of dermis
- Regrowth is possible with no permanent scars if infection is avoided
Third-degree burn
- Full-thickness burn
- Destroys entire thickness of cell
- Appears grey-white or blackened
- Regeneration is not possible
Stratum basale
Lies next to dermis, cells undergoing mitosis, daughter cells pushed upwards
Stratum spinosum
Spiny
Stratum granulosum
Granules of keratin, cells begin to keratinize/explode
Stratum lucidum
Made of dead cells of deeper strata, found in hands and feet
Stratum corneum
Shingle-like dead cells with keratin (prevents water loss)
