Cardiac Conduction and ECG

What is the significance of the refractory period in cardiac muscle?

• It allows the heart to contract continuously without relaxation.

• It prevents the heart from undergoing tetany and allows for proper filling of the chambers.

• It increases the heart rate during exercise.

• It enhances the strength of each contraction.

Which part of the heart's conduction system is located between the atria and ventricles?

• SA Node

• AV Node

• Bundle of His

• Purkinje Fibers

What does the P wave on an ECG represent?

• Contraction of the atria

• Relaxation of the ventricles

• Contraction of the ventricles

• Electrical activity of the heart

What does the T wave on an ECG represent?

• Contraction of the atria

• Relaxation of the ventricles

• Electrical activity of the atria

• Contraction of the ventricles

Tags

NGSS.HS-PS2-5

What does the QRS complex on an ECG indicate?

• Contraction of the ventricles

• Relaxation of the atria

• Electrical activity of the heart

• Blood flow to the lungs

What part of the heart's conduction system is responsible for transmitting impulses to the ventricles?

• Sinoatrial Node

• Atrioventricular Node

• Purkinje Fibers

• Bundle of His

What is the term for the circulation of blood to and from the heart muscle itself?

• Pulmonary circulation

• Systemic circulation

• Coronary circulation

• Hepatic circulation

What is the normal range for a resting heart rate in adults?

• 50 to 80 beats per minute.

• 60 to 100 beats per minute.

• 70 to 120 beats per minute.

• 80 to 140 beats per minute.

What is the function of the AV bundle in the cardiac conduction system?

• To conduct impulses from the AV node to the ventricles.

• To regulate heart rate by controlling the sinoatrial node.

• To initiate the contraction of the atria only.

• To prevent backflow of blood into the atria.

What is the primary purpose of coronary circulation?

• To supply blood to the heart muscle.

• To remove waste products from the brain.

• To transport oxygen to the lungs.

• To regulate blood pressure in the arteries.