Describe the structure of a neuron,its types based on processes,and their locations with examples.

(N/A) Neurons are the structural and functional units of the neural system.
The microscopic structure of a neuron consists of three main parts:
$(1)$ Cell body (Cyton),$(2)$ Dendrites,and $(3)$ Axon.
$(1)$ Cell body (Cyton): The main body of the neuron,which may be oval,round,or stellate in shape. It contains a central,large,round nucleus and cytoplasm called neuroplasm. The neuroplasm contains cellular organelles and characteristic basophilic granules called Nissl's granules,which are typically found near the nucleus.
$(2)$ Dendrites: These are short,branched processes that project out of the cyton. They also contain Nissl's granules and transmit nerve impulses towards the cell body.
$(3)$ Axon: $A$ long,single fibre that conducts nerve impulses away from the cell body to a synapse or a neuro-muscular junction. The distal end of the axon is branched,and each branch terminates into a bulb-like structure called a synaptic knob. These knobs contain synaptic vesicles filled with chemicals known as neurotransmitters.
Types of neurons based on the number of axons and dendrites:
$(1)$ Multipolar: One axon and two or more dendrites. Found in the cerebral cortex.
$(2)$ Bipolar: One axon and one dendrite. Found in the retina of the eye.
$(3)$ Unipolar: Cell body with only one axon. Found usually in the embryonic stage.
Based on the presence of a myelin sheath,neurons are classified as:
$(i)$ Myelinated neurons: The axon is enveloped by Schwann cells that form a myelin sheath. The gaps between adjacent myelin sheaths are called nodes of Ranvier. These are found in cranial and spinal nerves.
$(ii)$ Non-myelinated neurons: The axon is enclosed by Schwann cells but does not form a myelin sheath. These are found in the somatic and autonomous neural systems.