WEEK 8 Flashcards
function of blood: transportation and what are the 6 locations it transports
- primary function is to deliver oxygen and nutrients to and removes waste from body cells and tissues
1) oxygen from lungs to cells
2) carbon dioxide from cells to lungs for exhalation
3) nutrients from gastrointestinal tract to cells
4) hormones from endocrine glands to target cells
5) drugs from the site on absorption to target cells and tissues
6) cellular wastes and by products to the kidneys for excretion
function of blood: define regulation and describe it ( x2)
def= blood help maintains homeostasis of all bodily fluids
- proteins and chemicals as ph puffers therefore help to regulate ph of bodily fluids
- blood osmotic pressure helps regulate the water content of body cells, mainly though interactions of dissolved ions and proteins
function of blood: describe protection ( x2)
- white blood cells protect against external threats such as bacterial pathogens
- wbc protect against internal threats, such as cells with mutated DNA that could become cancerous or body cells infected with viruses
what are the 5 characteristics of blood
- ph consists of 7.35- 7.45v
- temp at 38 degrees
- viscosity= 5x thicker than water
- colour varies with oxygen content
- volume is 8% of body weight
what are the 2 components of blood
- plasma and other elements
define plasma and describe the 2 major groups of them
def= primarily composed of water. dissolved within water are proteins eg nutrients
1) albumin= made by the liver, contribute to osmotic pressure of blood helps draw water from tissues into blood
2) globulins= immunoglobulins made by plasma cells, alpha and beat which is made by the liver
what are the 8 formed elements and describe them ( blood composition)
1- red blood cell= transport o2 and co2
2- white blood cell= defend against pathogens and attack abnormal cells
3- neutrophils= phagocytic
4- eosinophils= phagocytic release antihistamines
5-basophils= promotes inflammation
6- lymphocytes= cell immunity
7- monocytes= phagocytic engulfing pathogens or worn out cells
8- plateles= hemostasis
what are the 4 characteristics of red blood cells
1- no nucleus therefore cannot repair
2- no mitochondria- rely on anaerobic
3- no rer- do not synthesise proteins
4- structural proteins- maintain structure
define haemoglobin
large molecule made up of four global proteins, each of which is bound to one molecule of iron containing pigment haem which contains iron
define haemeostasis
process by which the body seals a ruptured blood vessel and prevents further loss of blood. three steps to this process: vascular plasm, formation of platelet plug and coagulation
what are the 2 characteristics of haemeostasis and describe them
1) vascular plasm= damage to the blood vessel triggers contraction of the smooth muscle in the vessel wall. decrease blood flow to the area
2) plateler plug formation= platelet binds to exposed collagen at the site of blood vessel damage and becomes activated.
define coagulation
complex cascade of enzymatic reactions resulting in the conversion of fibrinogen into fibrin. clotting can be divided intro 3 pathways dependent on clotting factors
describe the extrinsic, intrinsic and common pathway of coagulation
extrinsic= triggered when clotting factors outside the blood vessel leak into the blood
intrinsic= triggers when clotting factors come into contact with substances inside the blood vessel
common= fibrin forms the thread of the clot
define clot retraction
contractile proteins within platelets within the clot, undergo contraction. this brings the clot closer together.
- decreasing size of damaged area
- decreases residual bleeding
- permits healing
define fibrinolysis
- restores normal blood flow as the vessel heals, the clot must eventually be removed
describe the rhesus system
- classified according to the presence or absence of the D surface antigen
- process occurs following a transfusion with rhesus negative incompatible blood or more commonly Wirth the birth.
describe the walls of the heart (X4)
1- heart lied in the mediastinum 2/3 of the heart mass lying to the left of the bodies midline
2- outermost= pericardium which protects and confines the heart
3- middle myocardium is composed of cardiac muscle tissue and is responsible for the pumping action of the heart
4- endocardium= inner layer that forms the lining of the chambers of the heart
describe the 3 layers of the walls of arteries
1) tunica intima= composed of epithelial tissue and connective tissue. lines the chamber of the heart
2) tunica media= middle layer contains smaller muscle tissue in a framework of loose connective tissue
3) tunica externa= outermost layer, primarily composed of collagen fibres
describe blood flow ( x6
1- mean arterial pressure
2- cardiac output
3- vessel length
4- vessel diameter
5- vasoconstriction and vasodilation
6- blood viscosity
what are the 4 capillary exchange
1- Hpc= capillary hydrostatic pressure
2- Opc= capillary colloid osmotic pressure
3- Hpif= interstitial fluid hydrostatic pressure
4- Opif= interstitial fluid colloid osmotic pressure
