Ch 3 Integumentary System Flashcards
Functions of Integumentary System
act as two way protective barrier
regulate temperature
houses sensory receptors
secretes important fluids
Organs of integumentary system
skin
hair
nails
sebaceous glands
sweat glands
primary function of the skin
to protect
-keeps pathogens/harmful substances out
-keep critical body fluids in
-protects internal organs and tissues
Facts of the skin
largest organ in the body (>20 lb)
also called integument, and cutaneous membrane
sensory receptors
housed in middle layer of the skin
detects temp, pain, touch, pressure
messages from receptors travel to brain and spinal cord
sweat glands
produces sweat
sweat evaporate off skin and produce cooling effect
sebaceous gland
produce oil called sebum
sebum lubricates the skin, keep from being dry
Process of cooling skin
sweat evaporates
superficial blood vessels dilate to release heat through the skin
Epidermis
thin outer membrane layer of skin
composed of stratified squamous epithelium
arranged in overlapping layers (strata)
has no blood supply or connective tissue
Process of conserving heat
superficial blood vessels constrict to prevent heat escaping
subcutaneous layer serves as insulation
Dermis
middle, fibrous connective tissue layer of skin
(deeper layer of skin also called corium)
located between epidermis & subcutaneous
living tissue with blood supply
ridges formed creates unique fingerprint
subcutaneous layer
layer of fatty tissue below the skin
also called hypodermis
composed of fat cells (lipocytes)
protect deeper tissues of body and act as insulation against heat/cold
melanocytes
produce black pigment melanin that gives skin color
protect skin against UV rays
Basal layer of the epidermis
-cells continuously grow and push old cells towards surface in this layer. during this process cells that are being pushed up shrink, die, and fill with keratin
-keratinized cells overlap and allow skin to act as waterproof barrier
-layer also contain melanocytes
Accessory Organ : Hair
consist of follicle, root, shaft, and arrector pili muscle
hair grows as older keratinized cells are forced up
melanin give hair color
Structures housed in the dermis
hair follicles
sweat and sebaceous glands
blood and lymph vessels
sensory receptors and nerve fibers
muscle fibers
arrector pili muscle
contracts to make the hair shaft stand up
Accessory Organ: Nails
main part- flat plate of keratin called the nail body which is connected to underlying tissue by the nail bed
base of nail- lunula
nails grow from the root which covered by cuticle
free edge- exposed part needing trim
Accessory Organ : Sebaceous Gland
release sebum into hair follicles
lubricate hair and skin
secretions increase during adolescense
secreation decrease with age
Accessory Organ : Sweat Gland
aka sudoriferous glands, are coiled glands in the dermis
-sweat travel to surface via sweat duct and exit via sweat pore
-cools body as it evaporate
-sweat from apocrine glands produce body odor
Culture and Sensitivity (C&S)
Grows bacteria removed from infected area to identify infecting bacteria; also determine bacteria sensitivity to various antibiotics
biopsy (BX,bx)
removal of piece of tissue to examine under microscope
exicisional biopsy
removal of entire suspicious area of tissue for examination
exfoliative cytology
scraping cells from tissue to examine under microscope
frozen section (FS)
thin piece tissue cut from frozen specimen for rapid examination under microscope
fungal scrapings
scrapings from lesions that are cultured and examined under microscope
allograft
skin graft from one person to another
also called homograft
autograft
skin graft from a person’s own body
skin graft (SG)
transfer of skin from normal area to cover another site
