Answer:
Schwann cells or neurilemma cells are the cells which form the myelin sheath around neuronal axons in the peripheral nervous system (PNS) only.
Neurilemma is the collective term used for cytoplasm and nuclei present around the myelin sheath which helps in the regeneration process of nerves.
A Schwann cell surrounds the axon, invaginate it and the plasmalemma of the Schwann cells joins and from a double membrane structure called mesaxon. This mesaxon starts wrapping the axon in spiral fashion and cytoplasm start condensing into the compact myelin sheath.
Such plants are called vascular plants.
Provided that there's no diagram, most molecules have particular areas on the molecules, called the "active area" that act as a lock to a particular substrate's molecular structure, providing the key.
An enzyme's active area is only able to be "unlocked" by a certain substrate's "key".
A salmon can live out of water for 2 hours