Protists - Clade SAR Flashcards
SAR Clade
Highly diverse monophyletic supergroup of protists characterized by similarities in DNA
Stramenopiles, Alveolates, and Rhizarians
How did SAR Clade originate?
Secondary endosymbiosis where a non-photosynthetic eukaryote engulfed a photosynthetic red alga, leading to the acquisition of plastids
Stramenopiles
SAR CLade
Include most significant photosynthetic organisms: diatoms and brown algae, as well as non photosynthetic oomycetes
Diatoms
SAR Clade - Stramenopiles
Diverse unicellular algae and major components of marine phytoplankton that generates 20-50% of global O2
Unique b/c ace and have a glass-like cell wall made of silica
Brown algae
SAR Clade - Stramenopiles
Largest and most complex algae, primarily multicellular marine species of seaweeds
Lack true roots, stems, leaves, but share analogous structures to plans
Life Cycle of Brown Algae
Involves alternation of generations between multicellular haploid and diploid forms
Sporophyte stage: diploid sporophyte produce haploid zoospores
Gametophyte stage: zoospores develope into haploid male/female gametoples with produce gametes in mitosis
Oomycetes
SAR clade - Stramenopiles
Filamentous, heterotrophic stramenopiles including water moulds, white rusts, and downy mildews that used to be classified as fungi due to filamentous morphology
Decomposers or pathogens
Alveolates
SAR Clade
Distinguished by having membrane-bound sacs known as alveoli acting as a supportive, flexible skin
Includes dinoflagellates, apicomplexans, and ciliates
Dinoflagellates
SAR Clade - Alveolates
two flagella, prossess alveoli that support overlapping cellulase plates
Prolific in marine and freshwater ecosystems and responsible for toxic “red tides” during blooms
Apicomplexans
SAR Clade - Alveolates
Prasites of animals that propagate through infections cells (sprozoites)
Ex) Plasmodium which is responsible for malaria
Ciliates
SAR Clade - ALveolates
Utilize cilia for locomotion and feeding that feed on bacteria and smaller protists and reproduce during binary fission and are diverse due to conjugation
Ex) Paramecium
Rhizarians
SAR Clade
unicellular protists defined by genetic similarities and shared morphological trains, heterotrophs
Most are amoebas
Amoebas
Word describing the way something moves and feed through extension and retraction of pseudopodia which traps food and form a vesicle to digest it. NOT a morphological descriptor
