PHYS20009 Lecture Notes - Lecture 5: Carotid Sinus, Sympathetic Nervous System, Baroreceptor

• School: University of Melbourne
• Department: Physiology
• Course: PHYS20009
• Professor: Charles

Document Summary

* there are baroreceptors in the carotid sinus and aortic arch that detect changes in map. * parasy(cid:373)patheti(cid:272) o(cid:374)ly goes to the heart a(cid:374)d does(cid:374)"t i(cid:374)(cid:374)o(cid:448)ate the peripheral at all. *if there is an increase in blood pressure, this increases the firing of the baroreceptors, and they signal via the cardiovascular control centre in the brain to decrease the sympathetic output. * heart does not need neural stimulation to contract. * there is a change in electrical activity which results in calcium being released which causes contraction (there is a delay in electrical stimulation and contraction which is caused by release of calcium) * blood moves through the different chambers of the heart out into the periphery. * pacemaker cells: control the initiation of the changes in electrical stimulation, thus the contraction of the heart. Sa node set the pace of the heartbeat at 70 beats per minute. Av node directs electrical signals from atria to ventricles.