Question

A neuron is exposed to a drug that causes the blockage of Na⁺ leak channels. How will this drug affect the resting membrane potential of the neuron? 
W. The resting membrane potential in this neuron would initially become more positive.
X. The resting membrane potential in this neuron would become around +60 mV.
Y. The resting membrane potential would return to normal following activity of the sodium-potassium pump.
Z. The resting membrane potential in this neuron would become more negative.

The correct answer is: if only Z is correct can you explain mi all option in short answer w x y z

Answer 1

In a neuron, there are two leak channels in action, one for the potassium ions and another one for the Sodium ions. The number of Pottasium leak channels are more as compared to the Sodium leak channels. (Pottasium moves from inside the cell to outside whereas Sodium moves from outside the cell to inside). The drug blocks the Sodium leak channel, thus more positively charged Pottasium Ions will be moving out and due to that the more +ve ions come outside the neuron. Due to this, the resting membrane potential of the neuron will start becoming more negative. Thus the correct option is (Z).

W is wrong since the potassium is moving out and the potential will become more negative.

X is also wrong because the potential will not be a positive number.

Y is wrong because the drug is actually blocking a normally functioning channel and hence the membrane potential will not return to normal.