Answer:
The answer to the question: Electrical impulses or action potentials (AP) cannot propagate across a synaptic cleft. Instead, neurotransmitters are used to communicate at the synapse, and re-restablish the AP in the post-synaptic cell, would be, true.
Explanation:
Essentially, although the CNS, PNS and ANS (Central Nervous System, Peripheral Nervous System and Autonomic Nervous System) are electrical systems, that use the electricity generated through action potentials, that in turn, are created by the exchange of electrically charged ions from within and without the neuronal cells, these electrical impulses do not pass the pre-synaptic, and post-synaptic cleft. Instead, once an AP has reached the terminal end of the pre-synaptic neuron, neurotransmitters are released by this one, into the cleft, which are then taken up by the receptors present in the post-synaptic neuron. Depending on the type of transmitter released, there will be an inhibitory or excitatory effect. Then, with the transmitter attached, the post-synaptic neuron will depolarize and a new AP will be generated in the post-synaptic neuron, which will carry on. Messages, thus are transmitted that way between neurons, and also, between the nervous system and the organs they influence.
