With respect to the generation of nerve impulse, consider the following statements and identify the correct statement: a) Any change to the membrane will cause Na + to enter into the membrane. b) As a

Question

With respect to the generation of nerve impulse, consider the following statements and identify the correct statement:
a) Any change to the membrane will cause $Na^{+}$ to enter into the membrane.
b) As a result, the potential difference is lowered.
c) This makes the membrane more permeable to $Na^{+}$
d) So there will be rapid influx of $Na^{+}$

TestHub · Accepted Answer

Statement (a) is incorrect because not "any" change to the membrane causes $Na^{+}$ to enter. For example, an inhibitory stimulus can cause hyperpolarization by opening $K^{+}$ or $Cl^{-}$ channels, which does not lead to $Na^{+}$ influx.

Statement (b) is contextually linked to the incorrect premise in (a). While a depolarizing stimulus does lower the potential difference, it is not the result of "any" change.

Statement (c) is correct. When a threshold depolarizing stimulus is applied, voltage-gated $Na^{+}$ channels open, making the membrane highly permeable to $Na^{+}$ .

Statement (d) is correct. The increased permeability to $Na^{+}$ leads to a rapid influx of $Na^{+}$ ions down their electrochemical gradient, which reverses the polarity of the membrane and generates an action potential.

Therefore, only statements (c) and (d) are correct.

Answer: c and d only

Biology - Neural Control and Coordination Question with Solution | TestHub

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