The given diagram is the representation of two neurons connected by the chemical signal. Each neuron has a nerve fiber that carries the nerve signal from one neuron to another covered with sheath, this body is called Axon.
Axon is connected with dendrite, which receives a signal from other neurons and is arise from the cell body of neurons in various numbers. The site where two neurons meet called synapse which is releases neurotransmitters a chemical signal molecule.
