NEET PG DENTAL EXAM

Detailed explanation-1: -The myelin sheath is a greatly extended and modified plasma membrane wrapped around the nerve axon in a spiral fashion [1]. The myelin membranes originate from and are a part of the Schwann cells in the peripheral nervous system (PNS) and the oligodendroglial cells in the central nervous system (CNS) (see Chap.

Detailed explanation-2: -Neurilemma (also known as neurolemma, sheath of Schwann, or Schwann’s sheath) is the outermost nucleated cytoplasmic layer of Schwann cells (also called neurilemmocytes) that surrounds the axon of the neuron. It forms the outermost layer of the nerve fiber in the peripheral nervous system.

Detailed explanation-3: -Schwann cells are derived from the neural crest and play crucial roles in the maintenance and regeneration of the motor and sensory neurons of the peripheral nervous system (PNS). They are mainly required for insulating (myelinating) and supplying nutrients to individual nerve fibers (axons) of the PNS neurons.

Detailed explanation-4: -Schwann cells, also called neurolemmocytes, have two structural types. They may form a thick myelin sheath, or an indented plasma membrane that folds around peripheral axons in the PNS. Where a Schwann cell covers an axon, the outer cell surface is called the neurilemma. This shields the axon from interstitial fluids.