Answer: pulmonary veins.
- A pulmonary veins
- B pulmonary artery
- C aorta
- D vena cava
Correct answer: A. pulmonary veins
Explanation: The pulmonary veins bring oxygen-rich blood from the lungs to the left atrium.
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.