Integumentary System Flashcards
Skin types
Thick>no hair,palm and sole,fingerprints
Thin>hair,everywhere
Epidermis made of
Stratified squamous keratinesed epithelium
The cell types
Keratinocytes>90% produces keratine for protection
Melanocyte >melanin to protect from UV
langerhan>macrophage of skin
Merkel>sensitivity+nerves
Yellow vs red bone marrow
Yellow stem cells replaced with fat
Red , active stem cells
Dermal papilla
Dermis under the epidermis
Injury types
1st intention>clean, by scalpel of dr,limited scarring and contraction
2nd intention>unclean, ulcer, scars, edges do not close on each other
Stages of wound healing
Inflammation> neutrophils go to site of injury, after 3 days macrophages go
Proliferation> basal layer divides, dead and wounded cells replaced, Angiogenesis, granulation tissues appears
Maturation & remodelling> collagen white fibers deposited from fibroblasts s collagen tye 3 then becomes type 1. Newly formed blood vessels disappear
When is neovascularization and epithelial proliferation maximal
5th day
After scar maturation
No hair, no sweat
Fibroblast may
Turn into myofibroblast as in muscles to contract the wound in 2nd intention
Healing similarity
1st intention 90%
2nd intention farr
Granulation tissue
Soft pink granular appearance when viewed from wound surface due to proliferation of small blood vessels and fibroblasts
Keloid
Hyperplasia during Scar healing of connective tissue
Apoptosis vs necrosis
Apoptosis, blebbing and phagocytosis, programmed cell death, requires ATP, ladder like fragmentation, individual death
Necrosis, swelling, ATP depleted, lysis, inflammation, random fragmentation, group death
Importance of apoptosis
Normal physiological development
Development of immune systems
DNA damage and wounds repair
