PHYSIOLOGY
CARDIOVASCULAR PHYSIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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The firing of the sinoatrial node (SAN) causes ____
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The atria to contract and empty
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The ventricles to contract and empty
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The atria to relax and fill
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The ventricles to relax and fill
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Explanation:
Detailed explanation-1: -Acting as the heart’s natural pacemaker, the SA node “fires” at regular intervals to cause the heart of beat with a rhythmn of about 60 to 70 beats per minute for a healthy, resting heart.
Detailed explanation-2: -The sinus node continuously generates electrical impulses, thereby setting the normal rhythm and rate in a healthy heart. Hence, the SA node is referred to as the natural pacemaker of the heart.
Detailed explanation-3: -The sinus node generates an electrical stimulus regularly, 60 to 100 times per minute under normal conditions. The atria are then activated. The electrical stimulus travels down through the conduction pathways and causes the heart’s ventricles to contract and pump out blood.
There is 1 question to complete.