topic 12: integumentary Flashcards
what are the three layers of the skin
-epidermis
-dermis
-hypordermis
describe the structure of the epidermis
-layer of non vascular stratified epithelium cells of varrying thickness.
new cells are produced in the deepest layer (stratum corneum) of the epidermis and are pushed upwards to the surface
the surface cells are continuously lost as dead cells (scruf/dandruff)
what are the layers of the epidermis
-basal layer
-spinous layer
-grannular cell layer
-stratum corneum
BSGS
structure of the dermis
-made up of dense connective tissues made up of elastic and collagen fibres
-rich in blood supply, nerve fibres
-includes the hair follicle, sebaceous gland and sweat gland
structure of the hypodermis
-made up of loose connective tissues and fat
-contains elastic fibres-> giving skin flexibility
functions of the skin
-sensory
-protection
-production
-storage
-thermoregulation
-communication
(SPPTC)
explain the sensory function
-surface of the skin contains many nerve endings to detect, temperature, touch and pain
explain the protection function
skins acts as a barrier between internal structure and external environment
-prevent entry of miccroorganism
-prevent entry of toxic or harmful substances
-protect against damage from water loss and uv light
-protect unerlying structure from injury
explain production
skin has glands
sweat glands: secretes sweat
sebaceous gland: secrete sebum
scent gland: secrete phermones
uv light from sun convert 7-dipycholestrol present in sebum into vitamin D
explain storage function
skin stores fat and excess energy and keeps animal warm (hypodermis layer)
explain thermoregulation function
Heat loss – dilation of surface blood vessel
and sweating from the skin glands assists in
the loss of water that evaporate and cool the
skin surface
* Heat gain – constriction of surface blood
vessel conserves heat in the body
* Insulation – adipose tissue under the skin
insulates the body (preventing heat loss).
Hairs traps a layer of warm air.
explain the communication function
-colour of skin provides visual communication
-secretion of phermones
what are the different glands found in the skin
-sweat glands
-sebaceous glands
-tail glands
-anal glands
describe the sebaceous gland and its functions
where: surround the hair follicle
secretion: sebum
function: form a thin, oily, water repellant layer over skin surface
gives coat hair a shiny appearance
-prevent bacterial growth on skin surface (anticeptic properties)
describe the sweat gland and its function
sweat gland: open into hair follicle or to skin surface
function: sweat evaporates from skin surface-> colling down of body + removes some waste from the body