Question

What is the correct flow of depolarization in the heart?
a. AV node, purkinje fibers, bundle of his, SA node
b. SA node, purkinje fibers,
c. SA node, AV node, bundle of His, purkinje fibers
d. AV node, SA node, purkinje fibers, bundle of his

Answer 1

Answer: The correct answer is option c.

Explanation:

Cardiac conduction system is formed by specialized cardiac muscle cells which enable the heart to contract in coordinated fashion.

The main component of this system are:

• Sinoatrial node
• Atrioventricular node
• Bundle of His
• Branched bundle
• Punkinje fibers

SA node consists of cells known as pacemaker cells. These cells spontaneously generate action potentials which lead to the contraction of atria.

These potentials are then passed to AV node which relay them to bundle of His. These bundles are branched into right and left bundle which ultimately transfer these potentials to Purkinje fibers.

The potentials from these fibers lead to the contraction of ventricles.