NURSING EXAM QUESTIONS
PATHOLOGY AND GENETICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Atria contract
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Ventricles contract
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Atria relax
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Ventricles relax
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Detailed explanation-1: -The SA node starts the sequence by causing the atrial muscles to contract. That’s why doctors sometimes call it the anatomical pacemaker. Next, the signal travels to the AV node, through the bundle of HIS, down the bundle branches, and through the Purkinje fibers, causing the ventricles to contract.
Detailed explanation-2: -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.
Detailed explanation-3: -The atria contract with each heartbeat to move blood into the ventricles, and the ventricles contract to move blood out to the body. During AFib, the heart receives electrical signals that come from outside the SA node causing the atria to contract in a disorganized fashion.