What are the components of the integumentary system?
Cutaneous and Accessory
Fxns of the Integumentary System
Barrier, thermoregulation, sensations, Waste removal, immune, blood reserve, vit D synthesis
Major layers to the skin and they teype of tissue found in each.
Epidermis - stratified squamous epithelium
Dermis - areolar CT and dense CT
Subcutaneous layer or hypodermis - adipose and areolar CT
What is another name for skin?
Integumentary
What are some of the sensations the skin can detect?
Pain, pressure, temp and touch
How is the skin involved in homeostasis?
Provides info to the central nervous system about the state of the body plus its other fxns the skin participates in homeostasis.
What are the 5 layers of the epidermis from deep out
Stratum Basal
Stratum spinosum
Stratum Granulosum
Stratum Lucidum
Stratum Corneum
What is the fxn of stratum basal and what cells can be found there?
basal cells, merkel cells and melanocytes.
fxn: Layer interlocks with dermis and new cell production
What is the fxn of the stratum spinosum and what cells can be found there?
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
What is the fxn of the stratum granulosum and what cells can be found there?
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.
What is the fxn of stratum lucidum and what cells can be found there?
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.
What is the fxn of stratum corneum and what cells can be found there?
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
What are epidermal ridges?
The design of the stratum basal which has finger like extension down into the dermis. Provides more surface area to attach to the dermis.
What are keratinocytes?
cells that produce keratin
What is keratin?
tough fibrous protein component of nails, hair and calluses as well as the general integumentary surface.
What are melanocytes?
cells that produce melanin
What is 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.