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Medical Dictionary

quantum

play
noun quan·tum \ˈkwänt-əm\

Medical Definition of quantum

plural quanta \ˈkwänt-ə\play

  1. 1:  one of the very small increments or parcels into which many forms of energy are subdivided <a molecule of rhodopsin in the human eye can cause a response to a single quantum of light>

  2. 2:  one of the small molecular packets of a neurotransmitter (as acetylcholine) released into the synaptic cleft in the transmission of a nerve impulse across a synapse





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