Ranvier's nodes
Học thuậtThân thiện
Definition
Noun (plural)Small, periodic, unmyelinated gaps in the myelin sheath of a myelinated (medullated) nerve axon. These nodes are essential for the rapid saltatory conduction of nerve impulses.
Usage
The term "Ranvier's nodes" is a specific anatomical and physiological term used in neuroscience and biology. It is always used in its plural form to describe the series of gaps along an axon. * The action potential jumps from one Ranvier's node to the next, speeding up neural transmission. * Under a microscope, you can observe the regular spacing of Ranvier's nodes along the nerve fiber.
Advanced Usage
- The term is often used in the context of saltatory conduction, where the nerve impulse "leaps" between nodes.
- They are sometimes simply called nodes of Ranvier.
Variants and Related Words
- Node of Ranvier (singular): The singular form for one specific gap.
- Myelin sheath: The insulating fatty layer that is interrupted by the nodes.
- Axon: The long, slender projection of a nerve cell along which the nodes are found.
- Saltatory conduction: The mode of signal propagation facilitated by these nodes.
Synonyms
- Nodes of Ranvier (more common variant)
Related Phrases/Concepts
- To be located at the nodes: Describes ion channels and proteins concentrated in these gaps.
- Voltage-gated sodium channels are densely packed at the nodes.
Noun
- small gaps in the myelin sheath of medullated axons