The (i)___, controls both the heart rate and the stroke volume. There are two separate nerves from the cardiovascular centre to the sinoatrial node: the (ii)___, to speed up the heart rate and the (iii)___, to slow it down. (i) receives information from special cells called (iv)___, present in the aortic arch and in the carotid sinus.
(i) Cardiac centre, (ii) Sympathetic system, (iii) Parasympathetic system, (iv) Baroreceptors
There are two very important cardiac centres in the medulla called the vasomotor centre and the cardiovagalcentre. The vasomotor centre sends signals through the sympathetic nervous system which, in turn, controls the heart and vessels through the secretion of norepinephrine or noradrenaline. The cardiovagal centre, as the name suggests, sends signals through the parasympathetic pathway, specifically the vagal nerve. This centre is responsible mainly for decreasing the heart rate.The cardiac centres receive information from special cells called baroreceptors present in the aortic arch and in the carotid sinus.