Question

In the diagram of multipolar myelinated neurons given above, different parts have been indicated by alphabets. Choose the answer in which their alphabets have been correctly matched with the parts which they indicate?

(a) A-cell body B-Nissl body C- nucleus D-dendrites E-Naked portion of axon F-myelin sheath G-Node of Ranvier
(b) A-cell body B- Nissel body C- Naked portion D- Dendrites E- Nucleus F-myelin sheath G-Nodes
(c) A-cell B-Nissel body C- Naked portion D-Nucleus E-dendrites F-Myelin sheath G-node of Ranvier
(d) A-cell body B-Nissel body C-Dendrites D-Nucleus E-Naked portion of axon F-myelin sheath G-node of Ranvier

Answer 1

Hint: Short branched process that helps in nerve impulse conduction towards the cell body, arises from the cell body.

Complete answer:
The nervous system is made up of Neurons or the nerve cells which are the structural and functional units. It has various parts namely dendrites followed by the cell body, axon, and terminal dendrites. The cell body consists of the nucleus, nissel granules, and other cell organs. Axon is of two types myelinated and unmyelinated. The part that leaves the cell body is devoid of the myelin sheath and later axon is covered with a myelin sheath. The gaps between the myelin sheath are called Ranvier nodes.

Additional Information: - Nervous system is made up of numerous cells called Nerve cells or Neurons,
- A typical neuron has dendrites, cell body, axon, and terminal dendrites.
- Cell body consists of dendrites and inside it has a nucleus, nissel granules, mitochondria, and other cell organs.
- The part that leaves the cell body is the axon which is of two types namely myelinated axon and unmyelinated axon. Grey matter in the nervous system contains numerous myelinated axons and white matter contains unmyelinated axons.
- Myelin sheath is not continuous in axons. The gaps between the myelin sheath are called Ranvier nodes or nodes of Ranvier.
- Axon is the largest part of the nerve cell which may be up to one meter in length.
- The end of an axon is called the axon terminal which contains dendrites called terminal dendrites that connect to the other neurons.
So, the answer is “A-cell body B-Nissel body C-Dendrites D-Nucleus E-Naked portion of axon F-myelin sheath G-node of Ranvier”.

Note: - Cell body is also called Cyton or Soma or Perikaryon.
- Dendrites also contain Nissel bodies and Neurofibrils that help in impulse conduction.
- Neurons are of three types: unipolar, bipolar, and multipolar neurons.