Final answer:
The tiny space between the axon of a sending neuron and the dendrite or cell body of a receiving neuron is called the synaptic cleft, a key part of the synapse where neurotransmitters are released and signal transmission occurs between neurons.
Step-by-step explanation:
The tiny space between the axon of a sending neuron and the dendrite or cell body of a receiving neuron is called the synaptic cleft, also known as the synaptic gap.
The synapse includes not only the synaptic cleft but also the presynaptic and postsynaptic membranes and other structures associated with neurotransmitter release, binding, and signal initiation.
When an action potential reaches the axon terminal of the presynaptic neuron, neurotransmitter molecules are released into the synaptic cleft.
These molecules then travel across the gap and bind to receptors on the postsynaptic neuron, which can initiate a new action potential in this neuron, thus carrying on the neural signal.