Biology / Unit 9 Bio 2003 short lesson, about 20 seconds
The SAR Supergroup: Stramenopiles, Alveolates, and Rhizaria
Captions available
The idea
SAR groups three subgroups: stramenopiles and alveolates, whose photosynthetic members share a secondary-endosymbiotic chloroplast history, and rhizaria, united instead by shared genetic and cytoskeletal traits.
In practice
Rhizarians unite with stramenopiles and alveolates by cytoskeletal and molecular traits, not by a shared chloroplast history.
Where people slip
Not every SAR member is photosynthetic — some lineages lost their plastids or never had one.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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