cardiovascular system Flashcards
vascular shunt
redirection of blood flow to area where it is most needed
vasodilation
widening of blood vessels
vasoconstriction
narrowing of blood vessels
anticipatory rise
An increase in heart rate caused by an increase in activity of the sympathetic nervous system causing the adrenal glands to release adrenaline into the blood stream.
sub-maximal exercise
any activity that doesn’t exceed 85% maximum heart rate, causes cardiac output to remain relatively unchanged.
diastole
the heart filling with blood when relaxing
systole
the heart emptying the blood when contracting
maximal exercise
- cardiac output increases significantly
- untrained individuals cardiac output is 14-20 L/min.
- trained individuals - 25-35 L/min
chemoreceptors
detects increases in carbon dioxide and lactic acid and decreases in oxygen
baroreceptors
detects an increase in blood pressure
proprioceptors
detects increase in muscle movement
haemoglobin
oxygen carrying red pigment found in red blood cells
parasympathetic
controls the bodies ‘rest’ functons
sympathetic
controls your bodies responses (fight/flight response)
autonomic
controls things you don’t have concious control over
blood pressure
force exerted by the blood against the walls of the blood vessels
dual action pump
two seperate pumps that work simulateneously to pump blood to two different places
bradycardia
decrease in resting HR to below 60bpm
cardiac output
the amount of blood pumped around the body per minute
cardiac output formula
heart rate x stroke volume
stroke volume
the amount of blood pumped around the body per beat
venous return
the return of blood to the right side of the heart via the vena cava
myogenic
generates it’s own electrical impulse
arterio-venous difference (avo2)
the difference in the content of oxygen in the arterial blood arriving at the muscle and the oxygen content of the venous blood leaving it