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The Cardiovascular system - Coggle Diagram
The Cardiovascular system
health
cardiac arrest is often casued by the build up of LDL in the arterties surrounding the heart. this is bad cholestrol which blocks the blood from entering the heart
a stroke is the result of a burst blood vessel leading the the brain refraining enough oxygen and blood reaching the brain.
anticipatory rise
when our HR increases prior to exercise. helps te body transition smoothly into high intensity exercise. it occurs because of the activation of the sympathetic nervous system , and the brain signaalling for the secreion of adrenaline and noradrenaline.
redistribution of blood
chemoreceptors detect an increase of CO2 in the blood, signal to the vasomotor centre to trigger the sympathetic nervous system
capillaries and veins transporting the blood to the non essential organs vsoconstrict, where was veins and capillaries going towards the working muscles vasodilate, meaning more blood is flowing in the direction of the working muscles, where it is more needed
cardiac conduction system
SA recieved a signal telling it to increase HR. an electrical impulse is sent from the SA node around the righ atrial wall to the AV node. this recieves the impulse and so delays the closing of the bicuspic valve by 0.1s, allowing for more blood to flow into the ventricle
the impulse then goes to the bundle of his where it splits in 2 down the pirkinji fibres, which goes around the outer walls of the ventricle, leading to a contration, ejecting the blood out of the heart
starlings law
increased venous return
increased diastollic filling
increased elasticity of cardiac muscle
increased force of contraction
increased ejection fraction
receptors
proprioceptors: these detect an increase in movement at the tendon or muscle. important so that o2 can be delivered to the working muscle, so sends a signal to the medulla oblongata
chemoreceptors: detect a change in CO2 levels in the blood. important so that the sympathetic nervous system can be triggered so increase heart rate can pump more o2 around the body
Baroreceptors: detect an increase in blood pressure. detects a stretch in the artery walls when bp increases
transportation of o2
venous return
skeletal muscle pump: contraction and relaxation pushes blood towards the heart
respiratory pump: increasing and decreasing volume of the --- chamber pushes blood towards the heart
pocket valves: valves in the veins which open and close preventing the back flow of blood, always keeping it oving towards the heart
AVO2 diff
cardiovascular drift
occurs after long sustained exercise, as the hight rate increases slightly
occurs after 10 mins of exercise > HR increases > streoke volume decreases > fluid lost as sweat > reduced plasma volume >decreased venous return > increased cardiac output > need to cool body down