MEDICAL
HEART AND PERICARDIUM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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contracted
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relaxed
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Either A or B
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None of the above
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Detailed explanation-1: -The electrical depolarization results in simultaneous contraction of the atria, thus forcing any residual blood from the upper chambers into the lower chambers of the heart. The atrial contraction causes a further increase in atrial pressures.
Detailed explanation-2: -Every cardiac cycle (heartbeat) begins with the sinus node sending an electrical signal across both atria through specialized conduction tracts, which causes the atrial muscle to depolarize and contract.
Detailed explanation-3: -Depolarization is the process by which the cells of the heart become less negative and contract. When the cells are at rest, they are negatively charged or polarized. However, when an electrical impulse is generated, the cells become depolarized.