Question

With a neat labelled diagram explain the structure of a neuron.

[Review question: Pg. No: 227]

Answer 1

Cells of nervous system are highly specialized for transmitting the stimulus rapidly from one place to another within the body. We can identify 3 distinct parts in nerve cells.
They are:

• 1. Cell body or cyton
• 2. Axon
• 3. Dendrites

1. Cell body or cyton has a large nucleus and cytoplasm. The cytoplasm contains granular structure called Nissal’s granules. There are some projections arising from cell body.
2. These are called dendrite. They are sharp, branched, more in number.
3. One projection of the cyton is somewhat longer than remaining projections. This is called axon.
4. Some nerve cells have axon covered with sheath like structure. This sheath is called as Myeline sheath.
5. Gas or nodes present at regular intervals on myeline sheath are known as Ranvier Nodes.
6. Axon of a nerve cell is connected with Dentrites of a near by nerve cell to form a web like structure throughout body.