Sodium (Na⁺)is Unable to Cross a Membrane Until a Local

question 71

Multiple Choice

Sodium (Na⁺) is unable to cross a membrane until a local change in the membrane potential occurs.This suggests that Na⁺ transfer across membranes is controlled by a(n)

• A) voltage-gated ion channel.
• B) ligand-gated ion channel.
• C) stretch-gated ion channel.
• D) ion channel that is always open.
• E) ion channel that is always closed.

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