The interval of pacemaker signals from S.A.N to A.V.N is:
Correct answer: B. 0.1 second
- A. 1 second
- B. 0.1 second
- C. 2 seconds
- D. 0.2 second
Explanation
The sinoatrial node (SAN) initiates the heartbeat and sends signals to the atrioventricular node (AVN) with a delay of about 0.1 second. This delay is crucial for allowing the ventricles time to fill with blood after the atria contract, ensuring efficient cardiac function. The other time intervals suggested are either too long or too short, disrupting this critical timing and potentially leading to inefficient cardiac performance.
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About Cardiac Cycle and Heartbeat
The cardiac cycle describes atrial systole, ventricular systole and diastole, including pressure changes, blood movement and the opening or closing of heart valves. It also covers the conduction pathway from the sinoatrial node through the atrioventricular node, bundle of His and Purkinje fibres, and relates these events to heartbeat sounds.
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