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 (pī-rē′noid′, pī′rə-)
A proteinaceous structure found within the chloroplast of certain algae and hornwort bryophytes. It is thought to be a site where carbon is concentrated.

[New Latin pȳrēna, fruit stone; see pyrene1 + -oid.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Biochemistry) any of various small protein granules that occur in certain algae, mosses, and protozoans and are involved in the synthesis of starch
[C19: from pyrene2 + -oid]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
The main characteristics that distinguish members of the order Trentepohliales from other green chlorophycean algae are as follows: differentiated reproductive cells; the presence of [beta]-carotene and haematochrome (i.e., astaxanthin), which color the algal thallus yellow, orange, or red; the absence of a pyrenoid in the chloroplasts; unique flagellar apparatus; and transverse cell walls with plasmodesmata.