Integumentary System and Body
Membranes
The Skin and its appendages – hair,
nails, and skin glands
Anatomy/Physiology - NHS
Body Membranes
• Sheet-like layer covers and/or lines – hollow
organs, body cavities etc..
• Cutaneous – SKIN
• Serous – covers organs, lines cavities, and secretes
a thin watery fluid – lubricate, reduce friction
• Mucous – Secrete mucus to exterior surface, lines
the RT, GIT, and UG – keeps moist and soft
Body Membranes (Connective)
• Do not have
epithelial
components
• Smooth Slick
Coverings of Joints
• Secrete Synovial
Fluid - lubricates –
reduces friction
SKIN – Cutaneous Membrane
• Largest Organ
• Also called Cutaneous Membrane
• Membranes – cover/protect body surfaces –
line body cavities and cover the insides of
hollow organs
• 16% of body weight
Epidermis
• Outer layer of skin
• Several stratified
squamous – thin
• Tightly Packed
• Produces Keratin- tough
water proof material –
used for protection
• Produces Melanin –
pigment of skin
• Avascular
Dermis
• Deep layer of skin loosely
packed
• Mostly connective tissue
• Dermal Papillae – parallel
rows or peg like
projections
• Vascular
• Form Ridges
• Sensory
Hair - Appendage
• Follicles in dermis
produce hair –papilla
from birth
• Papilla is nourished by
blood vessels
• Roots and Shafts make up
hair
• Lunago – newborns hair
• Arrector pilli cause
“Goose Bumps”
Receptors - Appendage
• Nerve Fibers
• Pacinian Corpuscle – deep in dermis – detects pressure
• Meissner’s Corpuscle – shallow in dermis-located toward
the epidermal base – detect light touch
• Free nerve endings – detect pain
• Krause’s end bulbs – detect vibrations
Nails - Appendage
•
•
•
•
•
Filled with Keratin
Nail Root – nail underneath skin
Cuticle – groove where skin meets nail
Lunula – “little white moon”
Low Oxygen = cyanosis – blue color
Skin Glands
• Sweat (Sudoriferous) Glands – most
numerous – produce perspiration – excrete
waste such as ammonia and uric acid, help
maintain body temp
• Sebaceous gland – secretes oil for hair and
skin
FUNCTION - Protection
• PROTECTION:Melanin protects from
U.V. rays, Keratin is waterproof and
microproof
• Temp. Regulation: Removes up to 3,000
calories of heat a day
• Sensing: Senses Pain, Hot Cold, Touch Millions of “antenna”
Burns
• Causes: UV Light, Fire, Electricity, Acid
• Total area involved – “rules of nine”
• 1st degree – minor discomfort – reddening of skin
– only epidermis
• 2nd degree – deep epidermal and some , dermal –
blistering, damage sweat glands, oil glands, hair
• 3rd – complete destruction of the dermis –
insensitive to pain.
st
1
Degree
• 1st degree – minor discomfort – reddening of skin –
only epidermis
nd
2
Degree
• 2nd degree – deep epidermal and some ,
dermal – blistering, damage sweat glands,
oil glands, hair
rd
3
Degree
• 3rd – complete destruction of the dermis –
insensitive to pain. Scarring and lesions