lecture2.txt

Cutaneous and Accessory

Barrier, thermoregulation, sensations, Waste removal, immune, blood reserve, vit D synthesis

• Epidermis - stratified squamous epithelium
• Dermis - areolar CT and dense CT
• Subcutaneous layer or hypodermis - adipose and areolar CT

Integumentary

Pain, pressure, temp and touch

Provides info to the central nervous system about the state of the body plus its other fxns the skin participates in homeostasis.

• Stratum Basal
• Stratum spinosum
• Stratum Granulosum
• Stratum Lucidum
• Stratum Corneum

• basal cells, merkel cells and melanocytes.
• fxn: Layer interlocks with dermis and new cell production

• 8-10 layers of keratinocytes that migrated from stratum basal as well as dendritic cells which stimulate immune response
• fxn: Immunity stimulation and cell division to increase thickness

• 3 - 5 layers of karatinocytes that migrated from stratum spinosum.
• fxn: produce keratin making cells thinner and flater and membranes to thicken and become less permeable.
• produce keratohyalin which causes cells to dehydrate, die and form tight layer with keratin fibers.

• Found only in thick skin areas like soles and palms. Extra layers of dead cells.
• fxn: increase thickness and protection against pressure and wear and tear.

• Outermost layer of skin. 15-20 layers of dead keratincytes - full of keratin
• fxn: barrier layer. waterproof due to keratin. protect from loss and microbe entry

The design of the stratum basal which has finger like extension down into the dermis. Provides more surface area to attach to the dermis.

cells that produce keratin

tough fibrous protein component of nails, hair and calluses as well as the general integumentary surface.

cells that produce melanin

yellow-brownish pigment that is transferred to neighboring keratinocytes. This pigment gives the skin its color. All people have the same number and distribution of malanocytes. It is the activity level of the cells that vary between individuals.

localization of overactivity of melanocytes