Neurosis is characterised by

Draw labelled diagrams of the following:
$(a)$ Neuron
$(b)$ Brain
$(c)$ Eye
$(d)$ Ear

Trembling,depression,fear,and phobia are signs of:

Given below are two statements with respect to the neurotransmitter,dopamine.
Statement-$I$: Degeneration of dopamine-producing neurons causes Parkinson's disease.
Statement-$II$: Dopamine levels increase due to cocaine.
Choose the most appropriate answer from the options given below.

The $II$,$III$,$VI$,and $XI$ cranial nerves are . . . . . . respectively.

Explain the following processes:
$(a)$ Polarisation of the membrane of a nerve fibre
$(b)$ Depolarisation of the membrane of a nerve fibre
$(c)$ Conduction of a nerve impulse along a nerve fibre
$(d)$ Transmission of a nerve impulse across a chemical synapse