New potential generated in the post-synaptic neuron during transmission of impulse is:

Given below are two statements.
Statement $I$ - In chemical synapse,the rate of transmission of impulse is higher in homeotherms than poikilotherms.
Statement $II$ - In chemical synapse,the synaptic cleft has a width of about $3.8 \ nm$.
In the light of the above statements,select the correct option given below:

True about electrical synapses:
$(I)$. Pre and postsynaptic neurons are in very close proximity.
$(II)$. Pre and postsynaptic neurons are separated by a synaptic cleft.
$(III)$. Impulse transmission is very fast.
$(IV)$. Electrical synapses are common in our system.
Select the correct option.

Which of the following inhibits the enzyme acetylcholinesterase?

Synaptic fatigue is due to

Distinguish between:
$(1)$ Synapse and Neurotransmitters.
$(2)$ Myelinated nerve fiber and Non-myelinated nerve fiber.