Diversity of life: Survey of the kingdom protista / protozoa ("first animals")
Opening discussion questions
1) Which is more evolutionary advanced a bacteria cell or a protista cell?
2) Are protists beneficial or harmful?
3) What do protist need to survive?
4) What do the cells below have in common? Look at their structures.
1) General features of the Kingdom Protista
Miscellaneous category -not really a plant -not really an animal -not really a fungus |
-prefer liquid environments ( freshwater, marine or body fluids) - first eukaryotic cells - mostly unicellular; start to see multicellular organisms 3 basic categories 1) animal like: protozoa 2) plant like: algae 3) fungus like: slime molds |
1) Organized: Overall Cell Structure
Cell structure
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-no typical protista cell 1) vary in size: *usually unicellular; *some form colonies; *some form coenocytes (a massive cell unit with several nuclei) 2) vary in cell structures * most contain a nucleus; some have more than 1 * some organelles: mitochondria and or chloroplast * some have cell walls or a test (shell); others have plasma membranes * some have flagella, cillia; others have pseudopods |
3) Reproduction
reproduction
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- asexual and or sexual - asexual under favorable conditions -sexual under unfavorable conditions |
4) Breathing/Respiration
respiration |
-mostly aerobic; gases pass via diffusion |
5) Eating habits/Metabolism
metabolism |
3 general group 1) most are hetertotrophic (amoebas) -predator, parasite or symbiont -ingest food via endocytosis, diffusion and osmosis -undergo cellular respiration 2) autotrophic protists (algae) - obtain food via photosynthesis 3) heterotrophic and autotrophic combination |
6) Homeostasis
Respond to environment |
-respond to stimuli (light, temperature and chemicals) via chemoreceptors by changing shape |
7) Movement
Mostly motile |
-some sessile -some planktonic (floating) -some motile via flagella, cillia or psedopods ("false feet") |
Classification
Classification: Animal like or heterotrophic protist
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1) Phylum Sarcodina -Amoeba/ Pseudopod phyla -Example: amebic dysentery via food/water contamination 2)Phylum Soomastigina -Flagella phyla Example: Trypanosoma carried by tsetse fly causing African sleeping sickness 3) Phylum Ciliophora -Cilia phyla (Example: Paramecium) 4) Phylum Sporozoa: -Nonmotile -Example: Plasmodium: parasitic protozoa carried by mosquitos causing malaria |
Plant like protists |
Photosynthetic protists -some unicellular (euglena , dinoflagellates "red tides" or multicellular ( algae) |