do all neurons have the same action potential
Action potential In the early development of many organisms, the action potential is actually initially carried by calcium current rather than sodium current. The opening and closing kinetics of calcium channels during development are slower than those of the voltage-gated sodium channels that will carry the action potential in the mature neurons. The longer opening times for the calcium channels can lead to action potentials that are considerably slower than those of mature neurons.[10] Xenopus neurons initially have action potentials that take 60â€“90 ms. During development, this time decreases to 1 ms. There are two reasons for this drastic decrease. First, the inward current becomes primarily carried by sodium channels.[11] Second, the delayed rectifier, a potassium channel current, increases to 3.5 times its initial strength.[10]
Nervous system The nervous system is defined by the presence of a special type of cellâ€”the neuron (sometimes called "neurone" or "nerve cell").[4] Neurons can be distinguished from other cells in a number of ways, but their most fundamental property is that they communicate with other cells via synapses, which are membrane-to-membrane junctions containing molecular machinery that allows rapid transmission of signals, either electrical or chemical.[4] Many types of neuron possess an axon, a protoplasmic protrusion that can extend to distant parts of the body and make thousands of synaptic contacts;[12] axons typically extend throughout the body in bundles called nerves.