Heart Function and EKG Interpretation

The video explains how the heart functions as a muscle, driven by electrical signals. It details the role of the sinoatrial node in initiating heartbeats, the contraction of atria, and the function of the atrioventricular node in allowing ventricles to fill with blood. The signal pathway through the bundle of His and Purkinje fibers leads to ventricular contraction, pushing blood through the pulmonary and aortic valves. The process is recorded on an EKG, showing P, QRS, and T waves, representing different stages of heart activity.

What is the primary function of the heart as described in the video?

• To act as a continuous pump

• To produce hormones

• To filter blood

• To store blood

Where does the electrical signal that initiates each heartbeat originate?

• Bundle of His

• Atrioventricular node

• Sinoatrial node

• Purkinje fibers

What happens when the electrical signal spreads across the atria?

• The atria contract

• The blood is oxygenated

• The heart stops

• The ventricles contract

What is the role of the atrioventricular (AV) node in the heart's electrical system?

• To speed up the signal

• To slow down the signal

• To stop the signal

• To reverse the signal

What does the interval between the P and Q waves on an EKG represent?

• Ventricular contraction

• Heart relaxation

• Atrial contraction

• Pause for ventricular filling

Through which structures does the signal travel after the bundle of His?

• SA node

• Purkinje fibers

• AV node

• Atria

What does the Q wave on an EKG signify?

• Ventricular relaxation

• Heart stopping

• Atrial contraction

• Signal through the bundle branches

Which ventricle contracts first during the heartbeat?

• Both ventricles simultaneously

• Left ventricle

• Neither ventricle

• Right ventricle

What does the R wave on an EKG indicate?

• Contraction of the left ventricle

• Contraction of the right ventricle

• Relaxation of the ventricles

• Atrial contraction

What marks the relaxation of the ventricles on an EKG?

• P wave

• T wave

• Q wave

• R wave