Which chemical substance is responsible for the transmission of nerve impulses across the synapse from one neuron to another?

Assertion : The chemical stored in the synaptic vesicles are termed as neurotransmitters.
Reason : Synaptic vesicles release these chemicals in the synaptic cleft.

Which of the following statements are correct regarding electrical synapses?
$i.$ At electrical synapses,the membranes of pre- and post-synaptic neurons are in very close proximity.
$ii.$ Electrical current can flow directly from one neuron into the other across these synapses.
$iii.$ Impulse transmission across an electrical synapse is very similar to impulse conduction along a single axon.
$iv.$ Electrical synapses transmit signals using neurotransmitters like acetylcholine.
$v.$ Electrical synapse transmission is very fast.
$vi.$ Electrical synapses are rare in our system.

Alzheimer's disease in humans is associated with the deficiency of

$A$ nerve impulse is transmitted from one neuron to another through the junctions called

Explain the process of transport and release of neurotransmitter with the help of a labelled diagram,showing complete neuron,axon terminal and synapse.