NURSING EXAM QUESTIONS
HUMAN ANATOMY PHYSIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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opening of voltage-gated slow Ca2+ channels
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Closing of voltage-gated slow Ca2+ channels
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opening of voltage-gated slow Na+ channels
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Closing of voltage-gated slow Na+ channels
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Detailed explanation-1: -During this time, a large quantity of both calcium and sodium ions flows through these channels to the interior of the cardiac muscle fiber, and this activity maintains a prolonged period of depolarization, causing the plateau in the action potential.
Detailed explanation-2: -Calcium channels This means that the T-type channels contribute more to depolarization (phase 0) whereas L-type channels contribute to the plateau (phase 2).
Detailed explanation-3: -This phase is known as phase 2 and is commonly referred to as the plateau phase. This plateau phase allows for a longer muscle contraction and gives time for the nearby cardiac muscle cells to depolarize. This is important in allowing the heart to contract in a steady, uniform and forceful manner.