Neuron
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A neuron, neurone, or nerve cell, is a cell that is excitable, firing electric signals called action potentials across a neural network in the nervous system, mainly in the central nervous system, and
Golgi-stained neurons in human hippocampal tissue
Synaptic vesicles containing neurotransmitters
A signal propagating down an axon to the cell body and dendrites of the next cell
Drawing by Camillo Golgi of a hippocampus stained using the silver nitrate method
Action potential
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An action potential is a series of quick changes in voltage across a cell membrane. An action potential occurs when the membrane potential of a specific cell rapidly rises and falls. This "depolarizat
In saltatory conduction, an action potential at one node of Ranvier causes inwards currents that depolarize the membrane at the next node, provoking a new action potential there; the action potential appears to "hop" from node to node.
Giant axons of the longfin inshore squid (Doryteuthis pealeii) were crucial for scientists to understand the action potential.
Tetrodotoxin is a lethal toxin found in pufferfish that inhibits the voltage-sensitive sodium channel, halting action potentials.
Image of two Purkinje cells (labeled as A) drawn by Santiago Ramón y Cajal in 1899. Large trees of dendrites feed into the soma, from which a single axon emerges and moves generally downwards with a few branch points. The smaller cells labeled B are granule cells.