PHYSIOLOGY
GENERAL PHYSIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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All the statements concerning cardiac muscle cells are true except
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they are individual cells held together by desmosomes.
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they depolarize by allowing sodium to flow into the cell through a gap junction.
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they are connected to an intrinsic conduction system.
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they have fast calcium channels to contract quickly.
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Explanation:
Detailed explanation-1: -Thus, the correct answer is ‘They do not show striations’.
Detailed explanation-2: -So, the correct option is ‘They are connected by intercalated discs, through which action potential spread to all cells in the heart’.
Detailed explanation-3: -The importance of calcium-dependent signaling in the heart has been appreciated for decades. For example, it is well accepted that intracellular calcium release from the sarcoplasmic reticulum (SR) is required for cardiac muscle contraction.
Detailed explanation-4: -In cardiac muscle, a clear role in calcium signaling for calcium release from ryanodine receptors (RyR2) eliciting Calcium-Induced Calcium Release (CICR) is well documented.
There is 1 question to complete.