Answer : 2. "A synapse"
Explanation :

The junction between the axon of one neuron and the dendrite (or cell body) of the next neuron is called a synapse. At the synapse, electrical or chemical signals are transmitted from one neuron to another or to an effector cell, such as a muscle cell or gland cell. Synapses play a crucial role in the transmission of nerve impulses within the nervous system.