Biology A-Level
myelin sheath
What myelin sheath means in Biology A-Level, as defined for AQA.
Definition of myelin sheath
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Reference: AQA
The many layers of the Schwann cell's plasma membrane around the axon, rich in lipid and acting as an electrical insulator.
Topics that use myelin sheath
- Nerve impulses (A-level only) (AQA A-Level)
Related terms
- absolute refractory period
- axon and dendrites
- depolarisation
- differential membrane permeability
- local currents
- maximum impulse frequency
- nodes of Ranvier
- relative refractory period
Using myelin sheath in the exam
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