A neurobiologist explains to his students that the human nervous system is analogous to electrical circuits in homes. If the circuit wires are not insulated, they are likely to cause a short circuit. In this scenario, the insulation on the wires can be likened to the in the neural system.

A. cell body
B. terminal button
C. dendrites
D. myelin sheath

D) Myelin sheath

Explanation:

The basic functional unit of nervous system is neuron like we can say a wire is for electric circuit. Whenever a stimulus is received by sensory neurons an action potential is generated which travels across the neuron and carry the information. The information travels in form of electric impulse across the neuron.

The myelin sheath is made of schwann cell and purpose to insulate a neuron. It function as speeding up the information flow in the neuron and also provide insulation to the information due to its fatty and protein nature. There is gaps between schwann cells called as node of reservoir and information jump from on node to other. Any breach in myelin sheath could slower down the flow as well as loss of information.

D. myelin sheath

Explanation:

Myelin sheath is insulating layer around the axons in a neuronal cell. It is made up of protein and fatty acids. It protects the axons from external damage and speedup the flow of impulse in a neuron. Without myelin sheath an impulse can be interrupted or completely lost.

it would lead to upper respiratory infections and pneumonia.