lecture 5/6 integumentary/skeletal Flashcards
what is the integumentary system composed of
hair skin nails glands sensory receptors
order of skin layers
epidermis (superficial)
dermis
hypodermis/ subcutaneous
what does the epidermis do
resists damage & provides protection to underlying tissue
it is keratinized stratified squamous epithelium
what are the 4 distinct cells
keratinocytes
melanocytes
macrophages
tactile epithelial
what does the dermis do
provides temperature stability
prevents dehydration
what does the hypodermis do
anchors skin to underlying tissue and organs
stores fat as adipose tissue
insulates body
what are the most common skin cells
keratinocytes
90%
4-5 layers
produce keratin - protects skin from wound damage
what are the least amount of cells
tactile epithelial
located in deepest layer
detect touch sensations
what do macrophages do
provide immune response that protect us from microbes entering the skin
thick skin =
hairless
thin skin =
hairy
order in layers in the epidermis starting with deepest
stratum basale (deepest)
spinosum
granulosum
lucidum
corneum
what layer would need a skin graft if you injured it
stratum basale
water repellent layer
granulosum
strength and stability layer
spinosum
adds toughness to skin layert
lucidum
abnormal thickening layer -callus’
corneum
in keratinization what are cells doing
constantly moving up and continuously sloughing off
what are critial in would healing
fibroblasts
what are the 2 layers in the dermis
papillary
reticular
what is the papillary region
more superficial
made of areolar CT
contain collage and fine elastic fibresh
what is the reticular region
deeper
attached to hypodermis
dense irregular CT
bundles of thick collagen
hair follicles
nerves
sebaceous coming out of this layer
functions of the integumentary system (7)
thermoregulation
blood reservoir
protection
cutaneous sensations
excretion and absorption
synthesis of vitamin D
emotional expression
phases of deep wound healing (4)
inflammatory
migratory
proliferative
maturation
difference between hypertrophic scars and keloid
hypertrophic = raised scar in original wound space
keloid - raised scar larger than original wound space
