PHYSIOLOGY
MUSCLE CONTRACTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Sodium ions rush out of the cell, while potassium ions rush into the cell
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Calcium ions rush out of the cell, while potassium ions rush into the cell
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Sodium ions rush into the cell, while potassium ions rush out of the cell
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Calcium ions rush into the cell, while potassium ions rush out of the cell
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Detailed explanation-1: -Because sodium is a positively charged ion, it will change the relative voltage immediately inside the cell relative to immediately outside. The resting potential is the state of the membrane at a voltage of −70 mV, so the sodium cation entering the cell will cause it to become less negative.
Detailed explanation-2: -This receptor is a ligand-gated channel (also called a chemically-gated channel). Upon binding of the neurotransmitter ligand, the channel opens. The rapid diffusion of Na+ ions into the cell creates an action potential that leads to the cellular response, in this case, muscle contraction.
Detailed explanation-3: -Na+ rushes into the cell, driven by electrochemical gradients. As more Na+ enters, the voltage changes further and more voltage gated Na+ channels open. The membrane potential depolarizes to +30 mV. Decrease in sodium permeability-Voltage gated Na+ channels close after a few milliseconds of depolarization.