l Includes heterotrophs and various groups of photosynthetic protists
l Major characteristic: hairlike projections on the flagella
l Only reproductive cells are flagellated
l One smooth and one “hairy” flagellum
l Oomycota, Bacillariophyta (diatoms), chrysophyta (golden algae), Phaephyta (brown algae)
l Oomycota- water molds, white rusts, downy mildews = heterotrophic stramenopiles
l Resemble fungi in appearance but not closely related
l Cell walls made of cellulose
l Predominant diploid stage
l Biflagellated cells
l Filamentous body plans to absorb nutrients
l Large egg cell and smaller sperm
l Water molds=important decomposers in aquatic ecosystems
l Bacillariophyta- diatoms- unicellular marine and freshwater plankton
l Boxlike silica walls, glassy
l Asexual reproduction however eggs and sperm produced also
l Food- glucose polymer, laminarin
l Chrysophyta- golden algae- yellow and brown carotene and xanthophyll accessory pigments
l Unicellular, biflagellated
l Marine and freshwater plankton
l Some are mixotrophic
l When population becomes too high, many species form long-lasting cysts
l Phaeophyta- brown algae- largest and most complex algae
l Color due to accessory pigments in their plastids
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