Please tell me which one is TRUE or FALSE for the statements below:

Question

1. During the cardiac cycle the pressure in the left ventricle and right ventricle are approximately equal.

2. During isovolumetric contraction the left ventricular pressure continues to increase and eventually reaches a point where it exceeds the aortic pressure.

3. The aortic valve opens when left ventricular pressure equals aortic pressure.

4. In the absence of other influences the intrinsic rate of the sinoatrial node is between 80 and 85 beats per minute.

5. The QRS complex represents the wave of ventricular depolarisation that precedes the contraction of the ventricle

Answer 1

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