Chapter 5 Part 2 Flashcards
Located on thin skin- root plexuses are touch receptors - protect scalp from uv Ryas and decrease heat loss- consist of dead Keratinzed cells
Hairs
Superficial portion above skin -root; deeper portion penetrates skin
Shaft/root
Raises hairs causing “goose bumps”
Arrector pilli muscles
Surrounds hair root
Hair follicle
Base of hair follicle, contains matrix, site of cell division
Bulb (hair)
Partial or complete hair loss
Alopecia
Develop from stratum basale of epidermis
Skin glands
Associated with hairs in thin skin -absent in thick skin- secrete sebun (oil) preventing dryness -increased activity may cause acne
Sebaceous glands
3-4 million in body -release sweat onto skin surface -eccrine glands; regulate body temperature
Sudoriferous (sweat) glands
Mainly located in Axilla and produce a more viscous secretion
Apocrine glands
Located in external ear produce cerumen (ear wax)
Ceruminous glands
Tightly packed, dead, Keratinized epidermial cells
Nails
Visible portion
Nail body
Whitish, crescent shaped portion
Lunula
Site of cell division
Nail matrix
Located in palms,Palmer surface of digits and soles
Thick (hairless) skin
Lack stratum lucidum
Thin (hairy) skin
Controls body temperature by negative feedback
Thermoregulation
Lowers body temp
Sweating
Conserve body heat
Constrictions of blood vessels in dermis
Blood reservoir; store 8 to 10% of blood at rest in and adult- protection;barrier to microbes and chemicals -sensation; sense stimuli -excretes and absorbs substances -produces vitamin D
Skin functions
Only involves epidermis and does not bleed- stratum cells break contact with basement membrane and start migrating towards each other
Superficial wound
Stops the migration of cells once they contact one another
Contact inhibition
Stops the migration of cells once they contact one another
Contact inhibition
