Describe how nerve impulses are transmitted.

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jerichorayel eNotes educator| Certified Educator

Nerve impulses (action potentials) are electrical current that travels through the nerve cells that is directed to the nervous system that will eventually produce information. This information is processed in the brain for certain response or action. The transmission of nerve impulses starts with the activation of the nerve cell by changing the voltage across the wall of the axon of the nerve cell. This change in the voltage is due to the charges of ions in and out of the nerve cell. As the signals are transferred from the dendrites to the axon, a receiving nerve cell is waiting for the signals to be transferred. The axons of the first nerve cell transfer its signals through the release of neurotransmitters to be received by the dendrites of the next nerve cell. This phenomenon happens in the synapse

orchid101 | Student
The transmission of nerve impulse in the nerve fibre has been explained by the so-called membrane theory of nervous conduction. According to this theory, the impulse itself is a transient set of biochemical reactions occurring mainly at the cell membrane of the axon, and accompanied by a small and very brief change in electrical potential, known as the action potential. However, the action potential is not the nerve impulse itself, it is only a means of showing that a nerve impulse is passing. When an impulse passes a given part part of the axon, the cell membrane suddenly becomes much more permeable to positively charged ions than when it is at rest. Sodium ions then diffuse inwards, and potassium outward during the very small fraction of a second before the membrane recovers its resting properties and by means of active transport restores the previous distribution of Na+ and K+ ions.