- a spherical protein structure found within chloroplasts of certain algae and hornworts.
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Examples from the Web for pyrenoid
A pyrenoid lies in a fold of the chromatophore on the dorsal part.
The pyrenoid is evidently concerned in the formation of the chromatophore, or in its division.
Schmitz states that the chromatophore is thickened in the middle and contains a pyrenoid.
- any of various small protein granules that occur in certain algae, mosses, and protozoans and are involved in the synthesis of starch
C19: from pyrene ² + -oid
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012