Depolarizations

Part of speech: noun

Definitions

1. A process that reduces or reverses the polarization of a cell membrane, often crucial in neural activity and muscle contraction
2. The change in electric charge distribution across a membrane that moves the membrane potential closer to a neutral state, facilitating action potentials
3. A phenomenon in cellular biology where the usual electrical polarization of membranes is altered, impacting signal transmission in nerves and muscles

Etymology: "Depolarizations" is the plural of "depolarization," which is "depolarize" plus the noun suffix "-ation." The base verb is built from the prefix "de-" meaning "reverse or remove" and "polarize," which in turn comes from "polar," from the Greek "polos," meaning "axis" or "pole," and the suffix "-ize," which turns a noun or adjective into a verb meaning "to make or become." In electrochemistry and physiology, the sense shifted from the physical idea of an axis to the electrical state of a membrane. A resting neuron keeps a voltage difference across its membrane, and when that difference shrinks toward zero, the cell is said to depolarize. Each plural form counts separate events of this kind, such as the successive depolarizations that carry a nerve impulse along an axon or trigger a muscle fiber to contract.