cardiac conduction system

Question 1

what is the cardiac conduction system?

Answer 1

the cardiac conduction system is a group of cells found in the walls of the heart which are responsible for the electrical impulses that cause the heart to contract.

Question 2

what does myogenic mean?

Answer 2

myogenic is the capacity to generate its own impulses.

Question 3

what is the sinoatrial node (SAN) ?

Answer 3

a small mass of cardiac muscle found in the wall of the right atrium that generates the heartbeat.

Question 4

what is the atrioventricular node?

Answer 4

this node relays the impulse between the upper and lower sections of the heart.

Question 5

what is the systole?

Answer 5

when the heart contracts.

Question 6

what is the bundle of his?

Answer 6

a collection of heart muscle cells that transmit electrical impulses from the AVN via the bundle branches to the ventricles..

Question 7

what are the perkinje fibres?

Answer 7

muscle fibres that conduct impulses in the walls of the ventricles.

Question 8

what are the order of events that take place as part of the cardiac conduction system?

Answer 8

1) electrical signal begins in the SAN.
2) the electrical impulse travels through the atria, causing them to contract and pass blood into the ventricles, before reaching the AVN
3) a delay of 0.1 seconds then occurs whilst the atria fully contract.
4) the electrical impulse then travels down the bundle of his, which is located in the septum.
5) the bundle of his then separates into smaller branches called purkinje fibres. these spread around the ventricles and cause them to contract.