71. Given below are two statements:
Statement I: Glial cells form myelin around the axons of neurons
Statement II: Myelin enables the rapid transmission of action potentials down an axon
In the light of the above statements, choose the most appropriate answer from the options given
below
1. Both Statement I and Statement II are correct
2. Both Statement I and Statement II are incorrect
3. Statement I is correct but Statement II is incorrect
4. Statement I is incorrect but Statement II is correct

 

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Glial Cells and Myelin in Neuron Function: Explained

In the context of neuroscience, the interaction between glial cells and myelin plays a vital role in ensuring efficient signal transmission in the nervous system. The following two statements often appear in educational content related to this topic:

Statement I: Glial cells form myelin around the axons of neurons

Statement II: Myelin enables the rapid transmission of action potentials down an axon

Let’s evaluate the accuracy of these statements and identify the correct answer.

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Statement I: Glial Cells Form Myelin Around Axons of Neurons

Correct.
Glial cells are essential support cells in the nervous system. Among their many functions, myelination is one of the most critical. There are two main types of glial cells responsible for forming myelin sheaths:

• Oligodendrocytes in the central nervous system (CNS)

• Schwann cells in the peripheral nervous system (PNS)

These cells wrap around the axons of neurons and create a multilayered insulation known as the myelin sheath, which is crucial for fast and efficient electrical signal conduction.

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Statement II: Myelin Enables Rapid Transmission of Action Potentials

Correct.
The myelin sheath significantly enhances the speed of electrical impulses through a process called saltatory conduction. In this process, action potentials jump from one node of Ranvier (gaps in the myelin sheath) to the next, rather than traveling down the entire length of the axon. This mechanism greatly reduces signal transmission time and increases neuronal efficiency.

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Correct Answer: Option 1

Both Statement I and Statement II are correct.

Both statements are scientifically accurate and describe the fundamental roles of glial cells and myelin in the nervous system.

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Conclusion

Understanding the role of glial cells and myelin in neuron function is essential for grasping how the nervous system operates efficiently. Glial cells not only provide structural support but also form the myelin sheath, which is critical for the rapid conduction of action potentials. These mechanisms are foundational for proper brain and nerve function, and any disruption can lead to neurological disorders such as multiple sclerosis.