Mammoth Memory

Nodes of Ranvier (pronounced rawn-vee-ay) – gaps in axon insulation

These are gaps in an axon’s insulating sheath of myelin which help speed up the signal sent along the axon.

Nodes of Ranvier or myelin sheath gaps help to speed up signals in axons by conducting ions along the axon

Loads of reindeer (nodes of Ranvier) when they were young were made to jump a gap full of axes (axons) to see if they would eventually be good enough to be Santa reindeer.

Diagram showing the consecutive gaps of Ranvier and the myelin sheath

Myelin does not form a continuous sheath along the axon – it is divided by a periodic gap known as the node of Ranvier, named after the French physician and anatomist, Louis-Antoine Ranvier, who discovered it. These nodes help to speed up the signals sent along the axon.

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