Question

Given below is the ECG of a normal human. Which one of its components is correctly interpreted below?

• A. Peak P and Peak R together- Systolic and diastolic blood pressures
• B. Peak P- Initiation of left atrial contraction only
• C. Complex QRS- One complete pulse
• D. Peak T- Initiation of total cardiac contraction

Answer 1

The correct option is C Complex QRS- One complete pulse

P wave is formed when the atria (the two upper chambers of the heart) contract to pump blood into the ventricles.

QRS Complex is formed when the ventricles (the two lower chambers of the heart) are contracting to pump out blood. It is one complete pulse.

ST segment measures the end of the contraction of the ventricles to the beginning of the rest period before the ventricles begin to contract for the next beat.

T wave measures the resting period of the ventricles.

So, the correct answer is option C.