Editing Chloroplast (section)

==== Carotenoids ====
{{plain image with caption|File:Delesseria sanguinea Helgoland.JPG|''[[Delesseria sanguinea]]'', a [[red alga]], has chloroplasts that contain red pigments like [[phycoerytherin]] that mask their blue-green [[chlorophyll a|chlorophyll ''a'']].<ref name="Campbell-2009f" />|250px|right|bottom|triangle|#aa2040}}

In addition to chlorophylls, another group of [[yellow]]–[[orange (colour)|orange]]<ref name="Campbell-2009e" /> pigments called [[carotenoid]]s are also found in the photosystems. There are about thirty photosynthetic carotenoids.<ref name="Takaichi-2011">{{cite journal | vauthors=Takaichi S | title=Carotenoids in algae: distributions, biosyntheses and functions | journal=Marine Drugs | volume=9 | issue=6 | pages=1101–18 | date=15 June 2011 | pmid=21747749 | pmc=3131562 | doi=10.3390/md9061101 | doi-access=free }}</ref> They help transfer and dissipate excess energy,<ref name="Kim-2009" /> and their bright colors sometimes override the chlorophyll green, like during the [[autumn|fall]], when the leaves of [[Deciduous tree|some land plants]] change color.<ref>{{cite web|last=Shapley|first=Dan| name-list-style=vanc |title=Why Do Leaves Change Color in Fall?|url=http://www.thedailygreen.com/environmental-news/latest/why-do-leaves-change-color-0909|work=News Articles|access-date=21 May 2013|date=15 October 2012}}</ref> [[β-carotene]] is a bright red-orange carotenoid found in nearly all chloroplasts, like [[chlorophyll a|chlorophyll ''a'']].<ref name="Kim-2009" /> [[Xanthophylls]], especially the orange-red [[zeaxanthin]], are also common.<ref name="Takaichi-2011" /> Many other forms of carotenoids exist that are only found in certain groups of chloroplasts.<ref name="Kim-2009" />