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Question: Answered & Verified by Expert
The flat horizontal line in between the waves of ECG represents time when
BiologyBody Fluids and CirculationNEET
Options:
  • A there is no mechanical activity in the heart but there is electrical activity in the heart
  • B there is no electrical activity in the heart but there is mechanical activity in the heart
  • C there is no mechanical activity in the heart and there is no electrical activity in the heart
  • D there is mechanical activity in the heart and there is electrical activity in the heart
Solution:
2019 Upvotes Verified Answer
The correct answer is: there is no electrical activity in the heart but there is mechanical activity in the heart
Electrocardiogram ECG has P wave, QRS complex and T wave. The P wave is an upward wave and indicates atrial depolarisation, QRS complex indicates ventricular depolarization. T wave is an upward wave and indicates ventricular repolarisation. The flat horizontal line is called the isoelectric line. There is no electrical activity, but there will be mechanical activity. Example: ST segment indicates atrial contraction.

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