Question

In which of the following would the rate of impulse condition be greater?

A. a myelinated fiber

B. a nonmyelinated fiber

C. is equal in both fibers

Answer 1

The correct answer is A. Myelinated fiber.

Myelinated fibers  are covered by a sheath called myelin sheath.

myelin sheath is of lipid nature. Hence it acts as insulator and increases impulse conduction.

schwann cells make myelin sheath in PNS and oligodendrocytes make myelin sheath in CNS (brain and spinal cord).

The myelin sheath assembles sodium channels at nodes of ranvier for efficient impulse conduction.The impulses diectly jumps from one node of ranvier to another node of ranvier . This conduction is called Saltatory conduction.

Hence myelinated fibers have greater impulse conduction.