Fermentation is a metabolic process that converts sugar to acids, gases, or alcohol. It occurs in yeast and bacteria, and also in oxygen-starved muscle cells, as in the case of lactic acid fermentation.
pupil noun [C] (EYE PART). âº the âcircular âblack âarea in the âcentre of an âeye, through which âlight âenters: Pupils âcontract in âbright âlight, and âdilate in darkness. (Definition of pupil from the Cambridge Advanced Learners Dictionary & Thesaurus Â© Cambridge University Press).
When this muscle contracts, it reduces the size of the pupil. This is the pupillary light reflex, which is an important test of brainstem function. Furthermore, the pupil will dilate if a person sees an object of interest.he pupil is a hole located in the center of the iris of the eye that allows light to strike the retina. It appears black because light rays entering the pupil are either absorbed by the tissues inside the eye directly, or absorbed after diffuse reflections within the eye that mostly miss exiting the narrow pupil.