Integumentary System Flashcards
State the 4 main properties of the integumentary System
largest organ in the body
continuous with mucous membranes lining the body
includes skin and accessory structures (sweaty glands, hair + nails)
characteristics vary through body
identify and explain the 4 functions of the skin
protection-chemical,physical,biological
detection of outside world -touch,vibrations, pressure, temperature and pain
thermoregulation-insulation or evaporation
excretion-through glands eg salt/water/phrase
name the 3 layers of the skin
epedrmis(surface layer),dermis(middle layer) and hypodermis (deepest layer)
describe the histology of the skin
-epedrmis (E) and dermis (D) interlock as the epedrmis sits on basement membrane
-Epidermal ridge (ER) extends into dermis
-Dermis Ridge (DR) known as the dermal papille and projects into epedrmis
name the 4 specialised cells in the epedrmis
keratinocytes, langerhan cells, melanocytes, markel cell
explain the role of keratinocytes
produces fibrous keratin protein, provides strength to skin, hair and nails
explain the roll of langerhan cells
immune cells which originate in the bone marrow
define the role of melanocytes
they synthesize melaning
allow pigmentation of the skin,hair and parts of eyes and UV protection
define the roll of the markel cell
touch receptors
sensory nerve endings which end in tactile disk
varies throughout skin,present in skin without hairs
list the properties of “thin” skin
-covers most of the body
-4 layers of epedermis
-thinnest epedermis…eyelids (0.1mm)
-thickest epedrmis…back (30-40 X epedermis)
list the properties of “thick” skin
-5 layers of epedermis
-only found in sides if feet and hands epedermis (1.5mm)
-no hair follicles
describe the steps of the “renewal of the epedermis”
1) basal stem cells divide in stratum basal
2) daughter cells enter stratum spinosum
3) keratin fibres accumulate
4)gradually become flagged and die
5) takes 7-10 days to migrate
6)skin condition PSORIASIS caused by increased keratinocyte proliferation
describe the dermis (middle layer) of the skin
dermis is a connective tissue layer containinf, Collagen+Elastic fibres which give strength and flexibility
name the 2 layers of the dermis
dermal papille
reticular layer
what is contained within the dermis
blood vessels
nerves
glands
adipocytes
smooth muscle
hair follicle
macrophages
fibroblasts
lymphatics
name the common skin condition within the dermis
dermatisis-inflammation of the dermal layer
discuss “tension lines” and the skin
Collagen AND Elastic fibres run in bundles orientated in direction where force is applied during movement
when are tension lines more likely to heal
easier to repair and less scarring if an insicion is made parralell
(incision across clevage-longer healong)
(incision parralell-less healing)
describe the properties/functions of the hypodermis (deepest layer)
-loose connective tissue layer containing fat cells (adipocytes)
-connective tissue fibres interwoven with dermis
-protects underlying bone and muscle
-thins with age and varies throughout body
list the skin appendages
hair shaft
sabaceous
sweat glands
hair follicle
nails
describe the exocrine gland
mainly release secrtions directly into hair shaft (holocrine secretions)
where are exocrine glands NOT present
Palms or Soles
Lipid secretions (sebum) functions are?
prevent water loss/gain
inhibits growth of bacteria
lubrication
protects hair shaft and surrounding skin
name the 2 sweat glands in the body
appocrine sweat glands
eccrine sweat glands
describe the appocrine sweat glands
ducts open into the follicle
associated with odeour
present in axilliae pubic region, area of breasts
describe the eccrine glands
ducts open into epedermis
regulates body temp
not present in margin of lips, tympanic membrane and parts of external genetilia
state the functions of the skin receptors
-skin is filled with sensory receptors each type respond to specific stimuli (light touch heat pain)
-pain receptors=cold receptors (sense anything it comes into contact with)
-nerve fibres in skin send signalsnto brain (concious)
-conrols blood flow & adjust gland secretionz
what factors determine skin colour
pigments/blood circulation/thickness of stratum corneum
name the 3 skin pigments and describe them
melanin-most important in skin hair and eye colour
carotene -from carrots/yellow veg, soluble accumulates in the sacrum corneum and adipocytes of dermis
hemoglobin-PINK colouration of skin, found in blood of dermis
how is melanin made
produced by melanocytes
where on the body is there most likely to be lots of melanin
moles and nipples
where in the body is there less melanin
lips and Palms
what 3 things determine melanin production
genetics
hormones
exposure to light
what is albinism
genetic mutation resulting in deficiency in pigment
state the 2 types of melanin and what they don
eumelanin-black or brown
pheomelanin-RED responsible for red hairs and freckles
state the clinical problems with skin colour and describe then
cyanotic-rich in deoxygenated blood=bluish colour
juandice-high bilirubin in blood (from liver) yellow colouration
erythemia-redness of skin due to hypermia (inflammation or blushing)
pallor-pale/white skin due to poor blood supply
SKIN CINDITIONS MAY VARY IN PRESENTATION ON DIFF SKIN TYPES (palpation is a useful tool)
what is the most common skin condition in humans
acne (bacterial infection)
describe what acne does to the skin
sloughing off cells blocks hair follicle-producing pimple
affected by hormones,sebum and bacteria
attracts neutophillis-puss pockets
what worsens acne
oil based products
describe skin cancer
most common. skin condition due to UV from the sun
list the 3 typss of skin cancer and describe them
BASAL CELL-commonest, typically on face local spread
SQUAMOUS CELL-often bleed cured by removal
MELANOMA-least common but mostaggrssive
describe odemea
-excessive accumulation of lymph fluid, tissues swells and expands
-lymphatic system returns intersticial to blood and recirculate
-accumulation determined by the balance secretin and removal.
discuss an “intradermal injection”
-injected into skin (dermis)
-used for allergy and TB skin testing
-shllow angle (10-15 °)
-inner surface of forearm/back/upper chest
-very small volumes (0.01-0.05ml)
what are the ztep by step instructions of an intradermal injection
1.stretch skin
2.insert needle 2-3mm with level up at shallow angle (15°)
3.needle should be visible under skin.
describe a subcutaneous administration
-into subcutaneous muscle tissue (below dermis)
-ccommon mode of aadministarting insulin and herpon
-steeper angle (45-90°)
-outer surface of upper arm, top of thighs, abdoman or back
-small volumes (upto 1ml)
-onset (within 30minz)
list the instructions of performing a subcutaneous administration
1.pinch up a fold of the skin
2.hold needle like a dart and Peirce skin at 45-90° angle
describe an intramuscular administration
-into a muscle/muscle group (antibiotics, adrenaline,analgesics)
-deltoid OR gluteal region (ventrol or posterior approach)
-larger volumes (upto 4ml)
-onset (variable)
list the instructions of intramuscular administration
1.hold needle like dart and insertquickly
2.aspirate to check for blood (blood vessel)
3.administer slowly and steadily
describe an (IM) deltoid
this is given in the arm, usually given quite high on the shoulder
state the ‘main danger’ when performing an IM deltoid
the radical nerve which runs near lower deltoid
describe an IM: lateral vastus
given in the thigh (laterally in middle 1/3 of thigh) parts of quadriceps muscle
state the least dangerous site of IM lateral vastus
nerve and blood supply well away from injection site
describe an IM: ventral gluteal
1.palm of hand above or greater trochanter of femur
2.index finger on ant superior lilac tubercle
3.injection site in the triangle (formed by index snd middle finger) gluteal medius
state the “danger zone” in IM ventral gluteal
sciatic nerve
describe an intravenous administration
-into a superficial vein (fluid, blood sampkes, ion substitutes)
-typically cubital fossa
-into MEDIAN cubital view
-largee volumes (but very slowly)
-onset:immediate
name the “danger zones” when performing intravenous administration
brachial artery
median nerve
