Control And Regulation Of The Cardiac Cycle.

Question 1

What does the Sinoatrial (SA) Node do?

Answer 1

The SA Node initiates the heartbeat.

Question 2

What does the Bundle of His do?

Answer 2

Takes impulse from the AV Node to the bottom of the ventricles.

Question 3

What do the Purkinje Fibres do?

Answer 3

Conducts the impulse up the ventricle walls causing the heart to contract.

Question 4

What does the Atrioventricular (AV) Node do?

Answer 4

Receives the impulse from the atria and then sends signals to the ventricles after a short time delay.

Question 5

The location and role of the SA Node is?

Answer 5

Located in the upper wall of the right atrium.
Known as the ‘pacemaker’ it is responsible for the heart beat.
Ensures both atria contract simultaneously.

Question 6

The location and role of the AV Node?

Answer 6

Located at the bottom of the right atrium.
Delaying electrical impulses it receives from the SA Node.
Allows blood to empty from the atria into the ventricles.

Question 7

Purkinje Fibres.

Answer 7

Very fine specialised muscle fibres that rapidly transmit impulses from the AV Node to the ventricles.