Biology - Neural Control and Coordination Question with Solution | TestHub

BiologyNeural Control and CoordinationNeuron and Nerve FibresEasy2 minPYQ_2026

BiologyEasysingle choice

In medullated nerves ____ prevents flow of $Na^{+}$ and $K^{+}$ ions between axoplasm and ECF.

Options:

Answer:

Solution:

In medullated (myelinated) nerve fibres, the axon is covered by a myelin sheath. The myelin sheath acts as an electrical insulator and prevents the exchange of ions such as $Na^{+}$ and $K^{+}$ between the axoplasm and the extracellular fluid (ECF).

Because of this insulating property, ion exchange and action potentials only occur at the unmyelinated gaps known as the nodes of Ranvier, leading to saltatory conduction of nerve impulses.

Answer: myelin sheath

Stream:MHT_CET_MEDICALSubject:BiologyTopic:Neural Control and CoordinationSubtopic:Neuron and Nerve Fibres

⏱ 2mℹ️ Source: PYQ_2026

Doubts & Discussion

Loading discussions...