Answer: heart.
- A heart
- B liver
- C lung
- D kidney
Correct answer: A. heart
Explanation: The heart is the muscular pump of the circulatory system.
A single ECG cycle: the P wave marks atrial depolarisation (contraction signal), the large QRS complex marks ventricular depolarisation, and the T wave marks ventricular repolarisation (recovery) before the next cycle begins.
Concept context
Blood, lymph, the heart, the cardiac cycle, blood pressure, and ECG. High NEET weightage.