Sports science - heart

Question 1

List what is within the conduction system of the heart

Answer 1

• sinoatrial node (SA)
• atrioventricular node (AV)
• bundle branches
• purkinje fibres

Question 2

What is the function of the SA

Answer 2

• pacemaker
• initiates depolarisation

Question 3

What is the function of the AV

Answer 3

• passes depolarisation to ventricles
• brief delay to allow for ventricular filling

Question 4

What is the process of the conduction system in the heart?

Answer 4

1. action potentials originate in the SA node and travel across the wall of the atrium from the SA node to the AV node
2. action potentials pass through the AV node and along the AV bundle, which extends from the AV node through the fibrous skeleton into the interventricular septum
3. the AV bundle divides into the right and left bundle branches and action potentials descend to the apex of each ventricle along the bundle branches
4. action potentials are carried by purkinje fibres from the bundle branches to the ventricular walls