If this is the particular kind of axon that is 'myelinated', then it might have a layer of a special substance called myelin in sheathing the axon.

假设这是一种特殊的有髓鞘的轴突,它表面上会像鞘一样地包裹上一层,称为鞘磷脂的特殊物质

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Surrounding the axon is a myelin sheath, which is actually just insulation.

髓鞘将轴突包裹起来,实际上形成了一个绝缘层

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