The information received by a receptor at the end of a dendrite sets of a chemical reaction that creates an electric impulse.
What is an impulse?
An impulse is a progressive wave of electro-chemical activity along a nerve fiber that stimulates or inhibits the action of a muscle, gland, or other nerve cell.
Nerve impulses originate in the cells of receptor organs due to external or internal changes or stimuli. Anything or any event that evokes a specific functional reaction in an organ or tissue is called as a stimulus.
The electrical impulses travel to the cell body and along the axon to its end. Here the impulse sets of the release of some chemicals that cross the synapse.
A Synapse is a junction between two nerve cells, consisting of a minute gap across which impulses pass by diffusion of a neurotransmitter.
Neurotransmitters are endogenous chemicals that transmit signals across a synapse from one neuron to another “target” neuron.
The neurotransmitters start similar electrical impulses in the dendrites of the next neurons. This way, the nervous impulses travel from one part to the other part of the body. Such impulses are delivered to other cell, tissue or gland.
Image: NCERT- New Delhi
