3 large groupings of Protists

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Protists
Members of a Kingdom that is under reorganization
3 large groupings of Protists -protozoans
(animal like) -slime molds and water molds
(fungi like) -algae (plant like)
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Protozoans

• -animal-like protists
• are heterotrophic
• -free-living and parasitic types
• -live in aquatic environments

• 4 groups of protozoans (we will look at each in
  more detail)
• Mastigophorans (flagellates)
• Sarcodines (amoebas)
• Sporozoans
• Ciliates

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Mastigophorans (flagellates)
-move by one or more flagella -most are
free-living -an important parasite is
Trypanosoma -causes sleeping sickness
Found in Human Blood
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Giardia this protist causes cramps and
diarrhea Hikers disease from drinking
contaminated water
-these are the most closely related to
prokaryotes
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Euglena
Photosynthetic flagellates
Chloroplasts are atypical of mastagophorans -most
likely came from secondary endosymbiosis
Because they are photosynthetic sometimes they
get classified with the plant-like protists
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2) Sarcodines (amoebas)
-move and feed by pseudopodia -extension of cell
membrane -ingest other protozoans -
phagocytosis (creating a food vacuole)
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Sporozoans
-       all parasitic Plasmodium causes malaria
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Plasmodium has complex life cycle using 2 hosts
Plasmodium feeds off the hemoglobin of the red
blood cells
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Ciliates
-use cilia to move and feed -found in aquatic
environments -nearly all are free-living ex
Paramecium and Stentor
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Slime molds
Cellular slime molds
Have a unicellular and multicellular life
stage single celled amoeba like cells can
aggragate to form a multicellular state -find
each other by chemotaxis
Single and Multicellular
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Plasmodial slime mold
Found on moist decaying matter  
Plasmodial stage consists of single mass of
cytoplasm containing many nuclei (multinucleate)
Reproductive stage
Enters this stage when there is a food shortage
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Algae
most are photosynthetic
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DINOFLAGELLATES
-unicellular -some photosynthetic, some
heterotrophic -outer plates made of
cellulose -2 plates come together with flagella
between
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may cause "red tides" ? massive fish death from
toxins
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DIATOMS
unicellular, photosynthetic
surrounded by glassy shell of silicon -important
base of aquatic food chains
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GOLDEN ALGAE (Chrysophyta)
May be mixotrophic Have yellow brown carotene
and xanthophylls as accessory pigments
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Green algae (Chlorophyta)
-single celled -colonial -multicellular -chlorplas
ts similar to land plants ex Chlamydomona ,
Volvox
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volvox
Chlamydomonas is unicellular while volvox is
colonial. Each individual cell in volvox is very
similar to chlamydomonas
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    Multicellular algae Kelp, seaweed -are
multicellular -may be very large -lack true
stems, leaves, roots, and vascular systems
-not plants
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-have adapted to life at ocean margins
-analogous structures to plants -thallus ?
seaweed body -holdfast ? rootlike
structure -stipe ? stemlike structure - blade ?
leaflike structure
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GREEN ALGAE (multicellular)
Life cycle include an alternation of generations
which is similar to plants
These are the closest relative of the plants
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BROWN ALGAE include huge kelp forests
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RED ALGAE (Rhodophyta) -contain
phycobilins -accessory pigments that absorb blue
and green wavelength -have been found at great
depths ? other wavelengths filtered
out -found in tropics -some have a hard chalky
coating -may help in formation of reefs