What is the neurilemma and what is it function?

What is the neurilemma and what is it function?
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the plasma membrane surrounding a Schwann cell of a myelinated nerve fiber and separating layers of myelin

Function of the sternum?

The sternum protects the vital area right above your heart and lungs. It completes the rib cage, since the first to the seventh rib is connected to it by coastal cartilage.

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