6.17: Cardiovascular and respiratory disorders (Part 2 of 3, ECG)

Question 1

What is the function of the Sinoatrial node

Answer 1

Conducts current down atria and internodal pathways

Question 2

What does the SAN produce on an ECG

Answer 2

P-wave of ECG

Question 3

Function of atrioventricular node

Answer 3

Current slows down
Atrial muscle contraction

Question 4

Function of septum and His-purkinje system

Answer 4

Current travels through septum and bundle of HIS
Rapid conduction through left and right bundles-> purkinje fibres-> ventricular contraction

Question 5

What does the bundle of HIS and septum produce on an ECG

Answer 5

QRS complex - contraction
T-wave as cardiac muscle relaxes and membrane potential repolarises