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This question has haunted me for two years.

Wikipedia mentions :

A nerve is an enclosed, cable-like bundle of axons (the long, slender projections of neurons) in the peripheral nervous system. A nerve provides a common pathway for the electrochemical nerve impulses that are transmitted along each of the axons to peripheral organs.

Okay, my book also defines like that. But if the nerve runs only with bundles of axons, where then are their soma located?

They say nerves are formed of many axons bundled together. Now, if there are axons, there must be soma, but they do not form nerve & hence are not present in nerve. So, where are they? Are they present at the beginning of the nerve?

Also, nerves communicate with each other. Books picture this as two neurons one above other; the above one sends impulse through its terminals to the dendrites of the neuron below it. So, how do these two neurons constitute a nerve?? After all, they now contain the cyton?? So, how do neurons one above other form nerve as they now contain the soma??

PLz explain.

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Neurons or nerve cells typically have a dendritic region, an axon and a cell body. The axon is also referred to as a nerve fiber. The axon is typically the longest structure, while the dendrites are mostly situated close to the cell body. See the following figure 1:

nerve cell
Schematic of a nerve cell. Source: Prof. Brown.

Axons often bundle into nerves. For example, the peripheral nervous system contains many nerves. The cell bodies of the neurons that feed their axons into a nerve are organized into ganglions outside the nerve (Fig. 2).

ganglia
The peripheral nervous system and the location of the ganglia. Source: Miami College.

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  • $\begingroup$ Really sorry , sir. I mistook in writing nerve-fiber in place of nerve. Can you check it now?? $\endgroup$ – user10379 Aug 15 '15 at 14:03
  • $\begingroup$ @user36790 - how about now? $\endgroup$ – AliceD Aug 15 '15 at 14:34
  • $\begingroup$ Thanks, sir, for posting the pic. So, does that mean all the cell-bodies lie in ganglions?? I urge you earnestly to please at least mark a single nerve in the pic, please. Thanks in advance:) $\endgroup$ – user10379 Aug 15 '15 at 15:46
  • $\begingroup$ @user36790 : All the connecting lines are nerves in Fig.2. $\endgroup$ – AliceD Aug 15 '15 at 22:15

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