Equipping People To Make Sense Of What They Are Told
The Integumentary System is the - Skin – Hair – Nails - the body’s outer protective
cover.
The adjective cutaneous literally means "of the skin" (from Latin cutis, skin). Skin
- the outer covering of the body. In humans, it is the largest organ of the integumentary
system made up of multiple layers of ectodermal tissue, and guards the underlying
muscles, bones, ligaments and internal organs.
The skin plays a key role in protecting (the body) against pathogens and excessive
water loss. Its other functions are insulation, temperature regulation, sensation,
synthesis of vitamin D, and the protection of vitamin B folates.
Types of Sensor:
Free nerve ending - sense temperature, light touch, pressure, pain.
Meissner’s corpuscle - encapsulated nerve ending responds to light pressure.
Merkel’s disc - unencapsulated receptor sense faint touch and light pressure.
Ruffini corpuscle - encapsulated receptor reacts to continuous touch and pressure
in joint capsules (responds to rotational movement).
http://skin-care.health-cares.net/oily-skin-care.php Internet Page
Proksch E, Brandner JM, Jensen JM. (2008).The skin: an indispensable barrier. Exp
Dermatol. 17(12):1063-72
Madison KC. (2003). Barrier function of the skin: "la raison d'être" of the epidermis.
J Invest Dermatol. 121(2):231-41 Internet Page
Skin performs the following functions:
Protection - an anatomical barrier from pathogens and damage between the internal
and external environment in bodily defence; Langerhans cells in the skin are part
of the adaptive immune system.
Sensation - contains a variety of nerve endings (sensors) that react to heat and
cold, touch, pressure, vibration, and tissue injury.
Heat regulation - the skin contains a blood supply far greater than its requirements
which allows precise control of energy loss by radiation, convection and conduction.
Dilated blood vessels increase perfusion and heat loss, while constricted vessels
greatly reduce cutaneous blood flow and conserve heat.
Control of evaporation - the skin provides a relatively dry and semi-impermeable
barrier to fluid loss.
Aesthetics and communication - others see our skin and may assess our mood, physical
state and attractiveness.
Storage and synthesis - acts as a storage centre for lipids and water, as well as
a means of synthesis of vitamin D by action of UV on certain parts of the skin.
Excretion - sweat contains urea, however its concentration is 1/130th that of urine,
therefore excretion by sweating is at most a secondary function to temperature regulation.
Absorption - In addition, medicine can be administered through the skin, by ointments
or by means of adhesive patch.
Water resistance - The skin acts as a water resistant barrier so essential nutrients
aren't washed out of the body.
