Which of the following is $NOT$ under the control of the $Vagus$ nerve?

$I.$ The endocrine system provides chemical integration through hormones.
$II.$ The neural system provides an organized network of point-to-point connections for quick coordination.
$III.$ The neural organization is very complex in lower invertebrates.
$IV.$ The human neural system includes $CNS$ and $PNS$.
Select the correct statements.

Which of the following is an example of the action of the autonomous nervous system?

$ECT$ is

Which of the following actions does not occur in humans after sympathetic stimulation?

Give a brief account of
$(a)$ Mechanism of synaptic transmission
$(b)$ Mechanism of vision
$(c)$ Mechanism of hearing