Assertion : Non-myelinated nerve fibres do not possess nodes of Ranvier.
Reason : This is due to the absence of nissl's bodies in node of Ranvier.

Options

A. If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B. If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C. If the assertion and reason are false
D. If the assertion is false but reason is true

Answer

C

Explanation

Myelin sheath is a lipid rich insulating layer which cov ers some nerve fibres of nerve tissue. Such fibres are called myelinated or medullated nerve fibres. Each myelinated nerve fibre shows constrictions at regular intervals called nodes of Ranvire which results from interruption in the myelin sheath at those places. Non myelinated nerve fibres are not covered by any myelin sheath, consequently no nodes of Ranvier are present in them.