KHP 450: Electrical Conduction System & Cardiac Cycle

The pacemaker of the heart is located in the:

• AV node

• SA node

• Bundle of His

• Bundle branches

Which is located within the walls of the ventricles?

• Purkinje fibers

• SA node

• AV node

• AV bundle and branches

A cardiac cycle is:

• ventricular relaxation

• ventricular contraction

• equivalent to 1 complete heart beat

• a heart attack

Place the following in the correct order of electrical impulses through the heart?
     1. SA node
     2. Ventricular myocardium
     3. AV node
     4. Atrial myocardium

5. Bundle branches
    6. Bundle of His
     7. Purkinje network

• 1, 4, 3, 6, 5, 7, 2

• 2, 1, 5, 3, 4, 61 7

• 7, 5, 6, 2, 3, 4, 1

• 1, 4, 3, 5, 7, 6, 2

The left and right ventricles contract after receiving electrical impulses from the:

• Purkinje Fibers
• SA node

• Bundle Branches
• NA node

What is the contraction phase of a hearbeat called?

• diastole

• sinoatrial

• systole

• atrioventricular

 This triggers contraction in the atria

• SA node
• AV node
• QT node
• AV Bundles

What does depolarization result in?

• relaxation

• contraction

• repulsion

• attraction

What does repolarization result in?

• relaxation

• contraction

• attraction

• repulsion

During atrial contraction and ventricular filling,

• the AV valves are open
• the semilunar valves are open
• the ventricles are contracted
• the atria are relaxed