Nervous tissue comprises of the nerve cells or neurons. They are the longest cells of the body. Neurons are the structural and functional units of the nervous tissue. The elongated and slender processes of the neurons are the nerve fibres. Each neuron consists of a cell body or cyton with nucleus and cytoplasm. The dendrons are short and highly branched protoplasmic processes of cyton. The axon is a single, long fibre like process that develops from the cyton and end up with fine terminal branches. They have the ability to receive stimuli from within or outside the body and send ignals to different parts of the body. Many nerve fibres are bound together by the connective tissue.