Innervation of the Heart

Question 1

Function of this node serves as the pacemaker of the heart and initiates the heartbeat.

Answer 1

Sinoatrial node (SA).

Question 2

What is the vascular supply of the SA node?

Answer 2

SA nodal artery, which arises from the right coronary artery.

Question 3

This node receives impulses from the SA node and passes them to the AV bundle (of His).

Answer 3

Atrioventricular node (AV).

Question 4

What is the vascular supply of the AV node?

Answer 4

Posterior descending artery, which arises from the right coronary artery.

Question 5

This node transmits impulses from the AV node, down the interventricular septum to the ventricles.

Answer 5

AV bundle (of His).

Question 6

Does sympathetic or parasympathetic innervation increase heart rate?

Answer 6

Sympathetic innervation.

Question 7

True or False; Parasympathetic innervation arises from the T1-T4 spinal nerves?

Answer 7

False.

Question 8

True or False; Ganglia are intramural with the descending axons in the cardiac sheath in parasympathetic innervation?

Answer 8

True.

Question 9

Does sympathetic or parasympathetic innervation increase contractility?

Answer 9

Sympathetic innervation.