Injury to the $Vagus$ nerve ($CN$ $X$) in humans is not likely to affect which of the following?

$I.$ 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.

Stimulation of the sympathetic nervous system causes ....

Neurosis is characterised by

$A$: Postganglionic nerve fibers of the parasympathetic nervous system have acetylcholine,while the sympathetic nervous system has adrenaline (epinephrine) as the neurotransmitter.
$R$: The sympathetic nervous system inhibits intestinal peristalsis,while the parasympathetic nervous system stimulates peristalsis.

Distinguish between (Any four):
$(a)$ Afferent neurons and Efferent neurons
$(b)$ Impulse conduction in a myelinated nerve fibre and an unmyelinated nerve fibre
$(c)$ Aqueous humour and vitreous humour
$(d)$ Blind spot and Yellow spot
$(e)$ Cranial nerves and Spinal nerves