Why does the flow of signals in a synapse from axonal end of one neuron to dendritic end of another neuron take place but not in the reverse direction? Explain.

Explanation

Signals in a synapse flow from axonal end of one neuron to dendritic end of another neuron but not the reverse because when this electrical signal after reaching the axonal end releases a chemical called neurotransmitter. This chemical then moves towards the dendrite end of the other neuron which generates an electrical signal. Since the chemicals are absent at the dendrite of neuron, the impulse can travel only from one side. In this way it is ensured that nerve impulse travel in only one direction (unidirectional).