the innervation of the heart

Question 1

explain briefly the nerve supply of the heart

Answer 1

the heart is innervated by both sympathetic and parasympathetic fibers
sympathetic fibers arise from a center in the medulla oblangata called as the cardiac acceleratory center

parasympathetic fibers arise form the center in the medulla called as the cardioregulatory center

Question 2

the preganglionic fibers arise from which all segments

Answer 2

they arise form T1-T5

Question 3

Postganglionic sympathetic fibers terminate on what all structures in the heart
and activation of the sympathetic fiber results in what?

Answer 3

Postganglionic sympathetic fibers terminate on the sinuatrial and atrioventricular nodes, on cardiac muscle fibers, and on the coronary arteries.
it results in Cardiac acceleration,
Increased force of contraction of the cardiac muscle,
Dilatation of the coronary arteries.

Question 4

name the parasympathetic nerve that innervates the heart and where does the postganglionic fibers end

Answer 4

it is the vagus nerve and the post ganglionic fibers end in the sa node ava node and the coronary artery

Question 5

parasympathetic nerve stimulation results in?

Answer 5

Reduction in the rate and force of contraction of the heart
A constriction of the coronary arteries.

Question 6

what is the location of sa node

Answer 6

Located in back wall of the right atrium at the superior end of the crista terminalis in front of the opening of the superior vena cava.

Question 7

what is the location of the av node

Answer 7

located in the bottom of the right atrium near the septum just above the opening of the coronary sinus