WHY AND HOW IS THE MEMBRANE OF NEURON POLARISED ?
Please find below the solution to the asked query:
Neurons are excitable cells because their membranes are polarised. Neural membranes are polarised because selectively permeable ion channels are present on them.
In the resting state, the membrane of the nerve cell is more permeable to the K+ ions and impermeable to Na + ions. Also only 2 K + ions move inside for 3 Na + ions to come out of cytoplasm of axon called axoplasm. The membrane of nerve cell is also impermeable to negatively charged proteins present inside the axoplasm. Thus, it does not let them go out. As a result, the axoplasm has more concentration of negatively charged proteins than positively charged.
Na+ and K+. This makes the over all charge inside the axoplasm negative and outside the membrane becomes positive due to more number of Na+. Hence, the outer surface of the membrane possesses positive charge and the inner surface possesses negative charge. This is known as polarised membrane.
Hope this information will clear your doubts about Polarisation of membrane.
If you have any more doubts just ask here on the forum and our experts will try to help you out as soon as possible.