Consider the following statements: 1. Propagation of a nerve impulse in a myelinated nerve fibre is different from that of unmyelinated fibre. 2. The impulse actually travels by leaping through the nodes of Ranvier in an unmyelinated fibre 3. The local circuits occur only at the internodes and at each node, the action potential is boosted to the same height by ionic mechanisms. 4. In the rest of the internodes, such an exchange is not possible due to the presence of myelin sheath acting as an insulator. Which of the above statements are incorrect? (a) 1, 2 (b) 1, 3, 4 (c) 2 only (d) 2, 3

Consider the following statements: 1. Propagation of a nerve impulse in a myelinated nerve fibre is different from that of unmyelinated fibre. 2. The impulse actually travels by leaping through the nodes of Ranvier in an unmyelinated fibre 3. The local circuits occur only at the internodes and at each node, the action potential is boosted to the same height by ionic mechanisms. 4. In the rest of the internodes, such an exchange is not possible due to the presence of myelin sheath acting as an insulator. Which of the above statements are incorrect? (a) 1, 2 (b) 1, 3, 4 (c) 2 only (d) 2, 3
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Cells which envelop nerve fibres and form myelin sheath around the axon are

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Do myelin sheaths slow down or speed up nerve impulses?

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