Conduction System

Question 1

What is the role of the Sino-Atrial (SA) Node?

Answer 1

This is a specialised cluster of muscle fibres which are located in the right atrium, they are responsible for generating electrical impulses

Question 2

What is the role of the Atrio-Ventricular (AV) Node?

Answer 2

The AV node electrically connects the hearts atria and ventricles to coordinate beating in the top of the heart. And it can delay the impulse by 0.1 seconds

Question 3

What is the role of the bundle of His?

Answer 3

This travels down the septum, and is split into 2 branches. It carrys the impulse to each ventricle

Question 4

What is the role of the Purkinji Fibres?

Answer 4

They distribute the impulses through the ventricles, causing them to contract.

Question 5

What is the pathway of an impulse in the conduction system?

Answer 5

1. Sino Atrial (SA) Node
2. Atrio Ventricular (AV) Node
3. Bundle of His
4. Purkinji Fibres

Question 6

What is the first stage of the conduction system?

Answer 6

DIASTOLE

Question 7

What is the second stage of the conduction system?

Answer 7

ATRIAL SYSTOLE

Question 8

What is the third stage of the conduction system?

Answer 8

VENTRICULAR SYSTOLE

Question 9

What occurs in the diastole cycle?

Answer 9

Blood enters the atria from the vena cava and pulmonary vein. The atria and ventricles are relaxed

Question 10

What conduction takes place in diastole?

Answer 10

No impulse

Question 11

What conduction takes place in atrial systole?

Answer 11

Impulse from the SA node -> AV node

Question 12

What conduction takes place in ventricular systole?

Answer 12

AV Node -> Bundle of His -> Purkinji Fibres