Chapter 4 - Integumentary System Flashcards
What are the 2 components of the integumentary system?
Cutaneous membrane and Accessory structures.
What are the components of the cutaneous membrane?
Epidermis and dermis.
What are the components of accessory structures?
Hair, nails, and glands.
What are the functions of the integumentary system?
- Protects deeper tissues.
- Aids in heat regulation.
- Aids in excretion or urea & uric acid.
- Synthesizes vitamin D.
The integumentary system protects the deeper tissues from?
Mechanical damage, chemical damage, bacterial damage, thermal damage, uv radiation, and desiccation.
Epidermis characteristics?
Stratified squamous epithelium, lack of blood vessels, can divide, outer most layers are dead.
Epidermal cells?
Keratinocytes, melanocytes, langerhan, and merkel.
Layers of the epidermis?
Stratum germinativum, stratum spinosum, stratum granulosum, stratum lucidum, and stratum corneum.
Stratum germinativum?
deepest layer of cells, cells that divide repeatedly.
Stratum spinosum?
8 to 10 cell layers (living) melanin taken in by phagocytosis from nearby melanocytes.
Stratum granulosum?
3 to 5 layers of flat dying cells and contain dark-staining.
Stratum lucidum?
3 to 5 layers of dead clear cells found on palms and soles of feet.
Stratum corneum?
25 to 30 layers of dead flat cells, continuously shed, friction stimulates callus.
Types of skin?
Thick and thin.
Characteristics of thick skin?
Palmer and planter surface, about 30 layers of dead cells, and contains all 5 layers.
Characteristics of thin skin?
Rest of body surfaces, few layers of dead skin.
Epidermal ridges?
Increases area of contact for better grip.
Where is melanin made?
By melanocytes in the epidermis.
What increases melanin?
UV sunlight.
What do melanocytes convert what to melanin?
Tyrosine.
what are the types of melanin?
Eumelanin (black) and pheomelanin (red-brown).
What are freckles or liver spots?
Melanocytes in a patch.
What is a nevus?
A mole or benign localized overgrowth.
What is albinism?
An inherited lack of tyrosinase; no pigment.
What are other types of skin pigments?
Carotene and hemoglobin.
What is Carotene?
Yellow orange pigment (precursor of vitaminA) found in stratum corneum and subcutaneous.
What is hemoglobin?
Red, oxygen-carrying pigment in blood cells.
What is the dermis composed of?
Papillary layer and reticular layer.
What does the papillary layer consist of?
Areolar Ct, capillries and neurons and dermal papillae.
What does the reticular layer consist of?
Anchoring layer, large vessels, nerves, adipocytes, arrector pili muscle, and dense irregular CT.
What is the cutaneous plexus and location?
Network of arteries and veins. Located in the subcutaneous layer.
What is the papillary plexus and location?
Helps nourish epidermal layer. Follows epidermal/dermal boundary.
What causes stretch marks?
Weight can, weight loss, or growth.
What are stretch marks?
Fibers stretch, loose elasticity and break.
Another name for the hypodermis?
Superficial fascia/subcutaneous layer.
What does the hypodermis consist of?
Areolar CT, adipose CT, collagen & elastic fibers.
Purpose of hypodermis?
Adipose acts as insulator, holds major blood vessels and nerves, and stabilizes skin.
Features of hair?
On most surfaces, hair number fixed at birth.
Types of hair?
Vellus (peach fuzz), Terminal (guys have all over), and Intermediate (girls have on arms).
What does hair consist of?
Shaft, root, bulb, cuticle, cortex, and medulla.
Functions of hair?
Protection, reduction of heat loss, and sensing light touch.
What is the root hair plexus?
Sensory nerves surrounding follicle and detect hair movement.
What is the arrector pili?
Smooth muscle, moves hair, and causes goosebumps.
3 stages of hair growth?
Anagen, catagen, and telogen stage.
What is the anagen stage?
Lasts from 2 to 6 years and matrix cells at base of hair root.
What is the catagen stage?
Lasts up to 2 weeks and matrix xells inactive & follicle atrophies.
What is the telogen stage?
Hair follicle remains dormant and hair is eventually pushed out by new hair as cycle renews.
What causes hair color?
Melanin produced in melanocytes.
What causes brown/black hair?
Contains a large amount of eumelanin.
What causes blonde hair?
Contains little eumelanin.
What causes red hair?
Contains has high level of pheomelanin.
What causes gray hair?
Decline in all melanin production.
Types of glands of the skin?
Sebaceous, sudoriferous, ceruminous, and mammary.
What do sebaceous glands secrete and the 2 types?
Sebum (oil). With hair sebum released into follicle and without hair sebum secreted onto epidermis.
What do sudoriferous glands secrete and 2 types?
Sweat. Apocrine and eccrine (they are merocrine glands though).
What do eccrine sweat glands secrete and location?
Sensible perspirations (water, NaCl, urea). Found on most body surfaces (greatest on palms).
What do apocrine sweat glands secrete and location.
Produce viscous secretion. Located in axillae and groin.
Modified apocrine sweat glands?
Mammary and ceruminous.
Nail is composed of?
Nail body, nail bed, nail root, and lunula
What are burns?
Tissue damage & cell death.
What cause burns?
Heat, electricity, UV radiation, or chemicals.
What are the associated dangers of burns?
Dehydration, electrolyte imbalance, and circulatory shock.
Types of burns?
First, second, and third degree burns.
First degree burn?
Skin red & swollen; only epidermis damaged.
Second degree burn?
Skin red with blisters; epidermis & upper dermis damaged.
Third degree burn?
Gray-white or black; destroys entire layer.
Burns considered critical if?
25% of body 2nd degree or 10% 3rd degree.
Effects of aging?
Less hair, reduced blood supply, dermis tends to thin, drying of epidermis, and fewer melanocytes.
