Achemical found in the sacs within an axon terminal which, when released, has an effect on a nearby neuron is called a

It is known as the neurotransmitter. This is endogenous chemicals that empower neurotransmission. They transmit motions over a synthetic neurotransmitter, for example, a neuromuscular intersection, from one neuron (nerve cell) to another "objective" neuron, muscle cell, or organ cell.

Neurotransmitter

Explanation:

The neurotransmitters are the chemicals that are stored in sacs at the axon terminals which are released outside into the synaptic cleft to act on the nearby neuron.The neurotransmitters are nothing but chemical messengers that help to transmit the information from one neuron to another neuron. Such a synapse formed between two neurons wherein the communication takes place through the neurotransmitters is known as the chemical synapse.