anatomy preparation

arteriosclerosis - loss of elasticity, hardening of arteries reduces efficiency to disconsolate/vasoconstrict, effecting BP and vascular shunt mechanism. smoking and aging enhance arteriosclerosis

atherosclerosis- high levels of cholesterol/lipids deposited in arteries causing blockages. lack of blood flows through. fatty plaque.narrowing of the lumen.leads to high BP and hypertension

angina- part of heart muscle wall is o2 deprived during any physical state but especially when excercising. causes intense pain in chest.

heart attack-serious consequences of angina, can cause permanent damage blood clots and blocking of coronary arteries

venous return;
-pocket valves prevent backflow of blood back to the heart
-muscle pump are veins between skeletal muscle which squeeze blood back to the heart when contracting/relaxing
gravity-blood from upper body naturally returns to heart
respiratory pump- breathing becomes faster during excercise so abdomen and thorax pressure changes, increasing pressure in abdomen and squeezing large veins to force blood back to heart
-smooth muscle- muscle in middle layer of vein walls contracts and relaxes helps to pump blood through veins back to heart.

starlings law of heart
-SV dependent on VR. VR increases- SV increases and vice versa

stroke volume values- resting 60-90ml excercising 80-120 (untrained) 160-200 (trained)

cardiac control centre- medula oblongata in brain controls blood distribution through regulating heart. it tells SA node to speed up or slow down depending on rest/physical activity(causing more contraction of pjunkie fibres (systole) or less contractions.. (neural control) (inrtinsic control) (hormonal control)
proprioreceptors tell CCC that activit yhas increased
chemoreceptors tell CCC that lactic acid and co2 has increased
baroreceptors tell CCC that BP has increased

systolic BP- avg resting 120mmHg. occurs when more o2 is needed around the body. reflects ventricular systole. contraction phase.

diastolic BP- avg resting 80mmHg. reflects ventricular distole. relaxation phase.

cardiac output- amount of blood ejeced by heart ventricles in one minute.

hypertension- persistently high blood pressure 140/90 mmHg
hypotension- 90/60 mmHg or less- persistently low BP