node of Ranvier

any of successive regularly spaced gaps in the myelin sheath surrounding an axon. The gaps permit the exchange of ions across the plasma membrane at those points, allowing the nerve impulse to leap from one node to the next in so-called saltatory conduction along the axon. [Louis A. Ranvier (1835–1922), French pathologist]

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Psychology term of the day

January 22nd 2025

auscultation

n. a diagnostic method in which the examiner listens for sounds within the body either with the aid of a stethoscope (mediate auscultation) or directly by laying the ear on the surface of the body (immediate auscultation).