Structural Organisation In Animals Question 482
Assertion : Non-myelinated nerve fibres do not possess nodes of Ranvier. Reason : This is due to the absence of myelin sheath 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 is true but the reason is false
D) If both the assertion and reason are false
Show Answer
Answer:
Correct Answer: C
Solution:
Myelin sheath is a lipid rich insulating layer which covers 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 Ranvier 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.
BETA
