Question

This question is about the resting membrane potential (RMP): 1) describe the role that the passive sodium channels play in the RMP, 2) describe the role that the intracellular anionic proteins play in the RMP, and 3) describe what happens to the RMP when a chemically-gated channel is activated, resulting in the closing of a chloride channel.

Answer 1

1. Cell membrane have some proteins channel that passively (without the expense of ATP) moves Na+ and K+ ions along down their concentration gradient. This channels are called LEAKY CHANNELS. Cell membrane is more permeable to K+ ion than Na+ ions. Because membrane have more K+ leaky channels than Na+ leaky channels.Na+/K+ ATPase pump with the expense of ATP pump out 3Na+ ion and pump in 2K+ ions. It is aactive process. So, we can say that after the action of the Na+/K+ pump the concentration of Na+ is more in the outside and in case of K+ the concentration is more in the inside. Which make the inside of the cell comparetively more negetive than outside. If this ATPase pump keeps on active then the indide will be more and more negetive, and will cause hyperpolarization from restion potential(which we also called polarised state).So, for the rescue of the hyperpolarization state the leak channels allow Na+ and K+ to move across the cell membrane down their gradients (from a high concentration toward a lower concentration). Thus maintain resting potential of te membrane. Maintaining the resting potential.
2. The voltage gated channels open or closed in response to the voltage change in the membrane. When cell is in resting potential the voltage. Chloride gated channel pumped in Cl- ion inside the cell when open. But when cell is in resting potential the gated channel is remain closed.