anticipatory rise and heart rate responses Flashcards
what is the SAN
sino atrial node, the hearts pacemaker which sends an impulse through the atria causing them to contract
list the heart rate increases and decreases
rest(60-80bpm), anticipatory rise, rapid increase, steady state, steep decline, levelling off
what is the conduction system
stimulation of the heart
where is the SAN and is it myogenic
yes it is self regulating and it causes atrial systole(
where does the SAN send the signal
the atrio ventricular node, between the atria and ventricle
what does the AV node do
ventricular diastole(heart relaxes and expands receiving blood into both ventricles through atria) and relays the signal
what is the bundle of his
positioned in the septum, separates the signal into left and right branches(down the septum then up and around the ventricles), as the blood need to be forced out of the pulmonary artery and aorta
what do the purkeje fibres do?
spread the signal(to every muscular cell) caused ventricles to go through systole(contraction)
where does the cardiac control centre exist
the medulla obligate in the base of the brain
are the medulla obligate and the san connected
yes via two nervous system loops, the sympathetic and parasympathetic
what is the job of the sympathetic nervous system
stimulates the SA node via the accelerator nerve, telling the heart to beat faster
what’s the role of the parasympathetic control system
decreases heart rate, connected to the san via the vagus nerve
what’s the role of the parasympathetic control system
decreases heart rate, connected to the san via the vagus nerve
what are chemoreceptors
there’s one next to the medulla, they sense chemical changed such as pH changes and blood acidity increases/decreases. they stimulate the control systems
what are baroreceptors
detect increases and decreases in blood pressure, informs medulla to stimulate the control systems
