However, this requires a cell to maintain a negative electrical potential also known as the resting membrane potential (RMP). This is achieved due to the semi permeable nature of the plasma membrane and multiple V-gated ion channels that are found on it. In a nerve cell, when a dendrite receives a signal, a depolarization event occurs which causes the electrical potential to drop. If it reaches a threshold of (-55 mV) the fast V-gated Sodium channels activate at the axon hillock. This brings the membrane potential to +30 mV in a quick burst as the Na+ ions escape and the sodium channels inactivate. At this point the relatively slower V-gated K+ channels activate and the movement of K+ bring the membrane potential to -90 mV thus hyperpolarizing it. The V-gated K+ channel eventually closes and the membrane potential is brought to RMP (-70 mV) by the Cl- channels. The depolarization then travels through the nerve until it reaches another dendrite synapse or a Neuromuscular Junction
However, this requires a cell to maintain a negative electrical potential also known as the resting membrane potential (RMP). This is achieved due to the semi permeable nature of the plasma membrane and multiple V-gated ion channels that are found on it. In a nerve cell, when a dendrite receives a signal, a depolarization event occurs which causes the electrical potential to drop. If it reaches a threshold of (-55 mV) the fast V-gated Sodium channels activate at the axon hillock. This brings the membrane potential to +30 mV in a quick burst as the Na+ ions escape and the sodium channels inactivate. At this point the relatively slower V-gated K+ channels activate and the movement of K+ bring the membrane potential to -90 mV thus hyperpolarizing it. The V-gated K+ channel eventually closes and the membrane potential is brought to RMP (-70 mV) by the Cl- channels. The depolarization then travels through the nerve until it reaches another dendrite synapse or a Neuromuscular Junction