Cardiac Cycle and Electrocardiogram

Which component of ECG cycle shows ventricular systole (contration)?

• P

• QRS

• T

• U

In the diagram below, which part of the tracing represents the contraction of the atria?

• P

• T

• R

• S

The opening of semilunar valves is due to

• increased ventricular pressure

• decrease ventricular pressure

• increased aortic pressure

• increase in artrial volume

In the 3 second strip below, the heart rate is

• 7

• 60

• 80

• 75

Which component of the ECG cycle shows when the ventricles contract?

• V

• T

• QRS

• P

During the cardiac cycle, what happens when the atria fill?

• The pressure in the ventricles becomes greater than in the atria, closing the AV valves.

• The AV valves close, preventing blood from entering the ventricles.

• The pressure in the atria is greater than in the ventricles, forcing the AV valves open.

• The ventricles contract, pushing blood back into the atria.

Tags

NGSS.HS-LS2-3

What is the first event of the cardiac cycle as described in the learning material?

• The ventricles contract

• The atria relax

• The entire heart relaxes

• The atria contract

During which phase of the cardiac cycle is arterial pressure at its lowest?

• Systole

• Diastole

• Mid-cycle

• Peak contraction

What does diastole refer to in the cardiac cycle?

• Contraction of the heart

• Relaxation of the heart and filling with blood

• The frequency of the heartbeat

• The electrical impulses in the heart

When performing a posterior EKG, which of the following is the correct location for placement of lead V8?

• Right mid-scapular line

• Left mid-scapular line

• Right posterior axillary line

• Left posterior axillary line