Integumentary System: Anna made Flashcards
Skin Functions
-Protection
-Sensation
-Temperature regulation
-Absorption
-Vitamin D production: Calcium absorption, bone strength, muscle, neural, immune function
What type of tissue is epidermis
Keratinized stratified squamous epithelium
What type of tissue is Dermis
Dense irregular CT
Epidermal layers
Stratum basale
Stratum spinosum
Stratum granulosum
Stratum lucidum
Stratum corneum
Bad sons give lame cock
Stratum Basale
Deepest layer
Single layer of “basal cells” (epidermal stem cells)
-Rapidly reproducing cells
-Layer of epidermal regeneration
-Pushed superficially into stratum spinosum
Stratum Spinosum
-“Spiny layer”
-About 10 layers of keratinocytes
-Begin filling with keratin: Trauma-resistant protein
-Attached by desmosomes
-Membrane linker proteins
-Contribute to protective function of skin
Stratum Granulosum
-“Grainy layer”
-About 5 layers of keratinocytes
-Continue to fill with keratin
-Nucleus and organelles destroyed
-Cells flatten
-Produce granules of keratohyalin
-Crosslinks the keratin proteins to
strengthen barrier
Stratum Lucidum
-“Translucent layer”
-Several layers of dead cells
-Packed with eleidin
-Lipid-rich form of keratohyalin
-Waterproof layer
-Found only in “thick skin”
-Typically palms, soles, digits
-“Callus”
Stratum Corneum
-“Horny layer”
-About 30 layers of dead cells
-Flakes of keratin
-Continually sloughing off
-Dry, thick surface protects against
abrasion and infection
Melanocytes
-Found in stratum basale
-Produce melanin
-Protect against UV rays
Merkel Cells
“Tactile cells”
-Respond to light touch
-Release chemicals to stimulate neuron
-Found in stratum basale
Dendritic Cells
“Langerhans cells”
-Immune cells of the skin
-Destroy pathogens that have entered through epidermal abrasions
Nevus
pigmented skin lesion formed from a cluster of melanocytes; “mole”
Freckles
areas of increased melanocyte activity
Hemangiomas
skin discoloration due to abnormal proliferation of blood vessels; “birthmark”
Friction ridges
“epidermal ridges”; cause fingerprints
Dermis
-Deep to the epidermis
-Composed of CT
-Papillary and reticular layers
Papillary Layer
Top layer of dermis
-Loose areolar CT
-Dense capillary network
-Supplies nutrients to deep layers of
epidermis
-Temperature regulation
-Dermal papillae
-Epidermal ridges -> Fingerprints
Reticular Layer
Deep layer of dermis
-Dense irregular CT
-Accessory structures: Hair, Glands, Sensory receptors
Bulb
base of follicle
Papilla: capillary bed
Matrix: living cells divide to form hair
Root
hair from bulb to surface
Follicle
tube surrounding root
Arrector pili muscle
goosebumps
Alopecia
Autoimmune disorder where hair follicles are attacked
Diffuse hair loss
Hair sheds from all parts of scalp
Due to hormones, drugs, iron deficiency
Male pattern baldness
Loss of hair from crown of scalp first
Hirsutism
Excessive hairiness
Hyponychium
under free edge of nail
Eponychium
cuticle of the nail
Lunula
moon part of nail
Brittle nails
prone to splitting
Ingrown nail
edge of nail digs into skin
Onychomycosis
fungal infection
Spoon nails
nail is concave
Beau’s lines
growth interference
Vertical ridging
common and harmless
Sudoriferous Glands
-Produce sweat
-Have ducts
-Merocrine (eccrine)
-Apocrine (“pits & peri”)
Apocrine
(“pits & peri”)
-Scent glands
- sweat glands of armpits, groin.
-Become active in puberty
-part of the cell (with vesical) is pinched off to release the product
merocrine
-salivary gland and sweat gland(eccrine)
- vesicles fuse with the cell membrane to secrete the product of the gland
-type of Sudoriferous Gland (sweat gland)
-Thermoregulation
eccrine
merocrine sweat glands.
holocrine secretion
-sebaceous glands
-a mature cell dies completely (explodes) to secrete the product
Sebaceous glands
-Secretes into hair follicle
-Produce sebum (oils)
-Protect skin and hair
-Antibacterial
-Become active in puberty
Ceruminous glands
Earwax
Cutaneous Receptors
-Sensory receptors in skin that Provide information about external environment
-Neural structures that sense light and deep touch, vibration, pressure, pain, temperature, tickle, itch, etc
what layer of skin is tattoo ink injected
dermis
Hypodermis
-also called Subcutaneous Layer or superficial fascia
-made of Areolar and adipose CT
-Protection, energy storage, insulation
-Common drug injection site: Dense vascular network promotes rapid absorption
-Thickness/distribution influenced by sex hormones
Acne
-Plugged sebaceous ducts and hair follicles
-Begins during puberty
-Blackheads, pimples when infected
Regeneration
-Regrowth of damaged tissue with same cell
type
-Restores original function of tissue
Fibrosis
-Wound filled with scar tissue
-Collagen produced by fibroblasts
-Function of original tissue is lost
Stages of Wound Healing
1) Damaged blood vessels bleed into wound
2) Blood clot forms
3) Leukocytes clean wound of pathogens
and dead tissue
4) Granulation tissue forms: Vascular pre-CT
forms in wound
5) Epithelium regenerates/CT fibrosis occurs
Psoriasis
-Chronic autoimmune skin disease
-Keratinocytes attacked by lymphocytes
-Rapid overgrowth of new skin cells
-Patches of scaly white skin
-Symptoms: Itching, pain, cracked skin
-Treatments: Corticosteroids, UV light therapy
First degree Burn
- Redness, pain
- epidermis affected
Second degree burn
- Blisters, scars
- epidermis and dermis affected
Third degree burn
- Damage to tissue deep to skin; severe scarring
- Requires hospitalization
- epidermis, dermis, and subcutaneous affected
