Define integumentary system?
- Covers the entire body
- Meets mucous membranes
- Composed of skin and it's derivatives: hair,
- Nails, sweat, oil, mammary glands
- (cutaneous membrane)
What is the function of the integumentary system?
- Physical protection
- Regulation of body temperature
- Nutrition-vitamin D
- Immune defense
Name the two primary parts of the integumentary system?
- Cutaneous membrane (skin)
- Accessory Structures
The cutaneous membrane (skin) contains what three parts?
- Epidermis (upon)
- Hypodermis (below)
What three structures make up the accessory structures?
Where is the loose connective tissue, areolar located?
Directly underneath the epidermis
What is the dense irregular connective tissue?
- "Little net"
- Collagen fibers
What type of epithelium is the epidermis?
Name the cells of the epidermis?
- Merkel cells
- Langerhans cells
What are the function of Merkel cells? What type of cell is it?
- They allow the sensation of touch
- Nerve cells
What is the function of Langerhans cells within the cutaneous membrane?
- Looking of pathogens
What is the function of melanocytes withing the cutaneous membrane?
- Pigment producting (fixed connective tissue proper)
- Prevents U.V. damage
What are the most abundant cells within the cutaneous membrane?
- Form 4-5 layers
- Produce Keratin
From the basal lamina (basement membrane) name the layers of epithelium?
- Stratum Germinativum (basale)
- Stratum Spinosum
- Stratum Lucidum
- Stratum Corneum
What cells do the stratum germinativum contain?
- Basal cells (large stem cells)- mitosis
- attached to basal lamina
- Merkel cells
What cells do the stratum spinosum contain?
- Daughter cells-kerantinocytes
- Langerhans cells-immune system
What cells do the stratum granulosum contain?
- Large amounts of keratin and
- Keratohyalin granules cells die-
- tight interlocked layer of keratin fibers
Where is stratum lucidum found? What is the function?
- Only in thick skin
- Palms, soles of feet flattend
- Packed with keratin; glassy
- Extra protection and water resistent
What cells do the stratum corneum contain?
- Surface layer of flat, dead cells
- Surface coated with glands
- Sweat and oil
How many days does the skin move from germinativum to corneum?
How long does the skin stay at the stratum corneum? Why?
- 2 weeks
- It's moving away from the nutrient supply
What is Dermal Papillae?
Finger prints, grip
Name the two layers of the dermis?
What is within papillary layer of the dermis?
- Loose connective tissue (areolar)
- Blood capillaries
- Free nerve endings (sensation/pain)
- Dermal papillae-cone shaped (finger prints)
Where is the papillary layer of dermis located? How much of the dermis does it make up?
- Directly under the epidermis
- 1/5 of the dermis
What does the reticular layer of the dermis contain? How much of the dermis does it account for?
- Collagen fibers and dense irregular connective tissue
- Blood vessles, hair folicles, nerves, sweat, glands
- Oil glands
What is the function of the hypodermis? What does it contain?
- Stabilize the skin-independent movement
- Fat cells (adipocytes)
- Large arteries and veins-hypodermic needles
- (collagen fibers from dermis extend down to this layer)
What are hair follicles? What is their function?
- Epidermal structure
- Protects scalp from UV light
- Cushions a blow to the head
- Insulation for skull
- Guard entrances to the nostrils and external ear canal
- Sensory base of hair shaft=early warning system
- Arrector pili elevates hair
What gland surrounds every hair follicle?
- Sebaceous gland
- (looks like cauliflower)
Define sebaceous glands?
- Waxy, oily secretion into
- Hair follicles (holocrine)
What is the purpose of sebum?
Lubricantion and inhibits growth of bacteria.
What are the two sudoriferous glands?
- Merocrine (eccrine)
What is the function and purpose of the merocrine secretion of sweat?
- Numerous, widely distributed secretion 99% water
Where are apocrine glands located? When are they activated?
- Groin, nipples, armpits
- Begin secreting at puberty
- May contain pheromones
- Viscous, cloudy, odorous secretion-bacteria
What happens to the apical portion of an apocrine cell?
Pinches off and enters the lumen of the gland
What does holocrine mean?
Abnormal cell mass
What are the two types of cancer? Define them.
- Benign-does not spread
- Malignant-metastasized (moves) to other parts of the body
What is the ABCD rule?
- A-Asymmetry. Two sides of pigmented mole do not match
- B-Border Integrity. Borders of mole are not smooth
- C-Color. Different colors in pigmented area
- D-Spot is larger then 6mm in diameter