Ch 5 Integumentary system Flashcards
whats the largest organ
skin
integumetary derivitves
- Nail
- Hair
- Glands (sweat, sebaceous)
integumentary functions
- Protection
- Water retention
- Thermoregulation
- Metabolic regulation (vitamin D)
- Immune defense
- Sensory reception
- Secretion
3 layers of integument
epidermis
- superficial layer
dermis
- deep layer
hypodermis
- below dermis
epidermis
- Epithelium of skin
- Avascular
- Keratinized
- Stratified squamous
- Sparse nerve endings
cells of the epidermis
keratinocytes
stem cells
melanocytes
merkel (tactile cells)
Dendric (langerhans) cells
keratinocytes
synthesize keratin
stem cells
- Divide and produce keratinocytes
- Only in status basale
melanocytes
- Produces melanin
- Found in stratus basale
merkel (tactile cells)
- Touch receptors that join nerves
- Found In stratus basale
- Dendritic (langerhans) cells
- Immune surveillance
- Found in stratum spinosum, and stratum granulosum
Strata (layers) of epidermis
- From deep to superficial: (bottom to top)
- Stratum basale
- Stratum spinosum
- Stratum granulosum
- Stratum lucid
- Stratum corneum
- Stratum basale
- Attached to basement membrane
- Cell types:
- Keratinocytes
- Melanocytes
- Tactile cells
- Stratum spinosum
- Several types of keratinocytes
- Some epidermal dendrite cells (langerhans)
- Phagocytic cells that initiate immune response
- Stratum granulosum
- 3-5 layers of keratinocytes
- Cytoplasm fills with keratin filaments
- Organelles begin to degrade
- Stratum lucid
- Thin and translucent
- Present in thick skin (hands, feet)
- Lack organelles- contain eleidin
- Stratum corneum
- Thickness varies (20-30 layers of dead cells)
- Anucleated
- Migration of cells from basale to corneum ~ 2 weeks
- Thick skin
- Palms and soles of hands and feet
- No hair
- No sebaceous oil glands
- High sweat glands
- Adaptive for high friction
- Thin skin
- Covers most of body
- Hairy
- Has both sebaceous and sweat glands
Papillary layer of dermis
- Composed areolar connective tissue
- Dermal papillae - projections
- Interlock with epidermal ridges
- To increase surface area of region and protect
- Contains capillaries and sensory receptors
- Interlock with epidermal ridges
Reticular Layer
- Deeper region
- Primarily dense irregular connective tissue
- Includes:
- Blood vessels
- Glands
- Hair follicles
- Nerves
- Dermal blood vessels
- Help control body temperature and blood pressure
- Nerve fibers
- Monitor sensory receptors
- Control blood flow
- Control glandular secretion
Hypodermis
- Not part of integument
- Areolar and adipose tissue
- Functions:
- Protects underlying structures
- Store energy
- Thermal insulation
- Exocrine glands of skin
sweat glands
- Sebaceous glands
sweat glands
- Merocrine
- Apocrine
- Have coiled, tubular secretory portion deep layers
- Sebaceous glands
- Secrete oily sebum
- Lubrication: prevent drying
- Inactive during childhood
hair regions
hair bulb
hair root
hair shaft
hair bulb
where hair originates
hair root
deep to skin surface
hair shaft
extends beyond skin surfaces
arrector pilli muscles
attach to hair staff
lanugo
hair on fetus
villus
- Fine and non pigmented, on most of body
terminal hair
coarse and pigmented
atopic dermatitis
- Outer layer of skin has an alteration where allergens or viruses get into skin easy
first degree burn
sun burn
second degree burn
- Deeper and blistering
- To dermal layer
third degree burn
- Burns involve all layers of skin
fourth degree burn
- Burns extend to muscle and bone
- Life threatening
- Transplant needed
skin cancer
- Most common form of cancer
- Chronic sun exposure is main risk factor
three types of skin cancer
- Basal cell carcinoma
- Squamous cell carcinoma
- Malignant Melanoma (melanocytes)
