Answer: The correct answer for the blank is -
Chemical signal.
Step-by-step explanation:
Neuron is referred the basic unit of the nervous system that helps in the transmission of impulses throughout the body.
It is primarily composed of dendrites, cell body, axon, and axon terminal (nerve ending).
When electrical signal passes the axon and reaches terminals, certain chemical signals called neurotransmitters are released by the nerve endings into the synapse ( which is a space between two neurons). Thus, chemical signal is transferred to the next neuron, which is further converted to electrical signal. In this way, transmission of signals takes place throughout the body.