[ grey-nuh m ]
/ ˈgreɪ nəm /
noun, plural gra·na [grey-nuh] /ˈgreɪ nə/.
(in prescriptions) a grain.
Botany. one of the structural units of a chloroplast in vascular plants, consisting of layers of thylakoids.
Origin of granum
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for granum
The Spanish name grana, confounded with granum, may have given rise to this contest.
Science definitions for granum
[ grā′nəm ]
Plural grana (grā′nə)
A stacked membranous structure within the chloroplasts of plants and green algae that contains the chlorophyll and is the site of the light reactions of photosynthesis. The saclike membranes that make up grana are known as thylakoids. See more at chloroplast.
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