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KINGDOM PROTISTA PROTISTA Taxonomy Domain Eukarya Kingdom Protista Bacteria Archaea Protista Plants Fungi Animals 2 General Characteristics Cellular organization Most unicellular; some multicellular Size Microscopic >100 m in length Reproduction Asexual (binary fission or budding) OR sexual Metabolism Autotrophic, heterotrophic, or both 3 General Characteristics A “kingdom of convenience” Not fungi, plants or animals Volvox Amoeba Sea Palm Kelp Trichomonas 4 Diatoms Phylogeny diplomonadsFlagellated Continual flux parabasalids Protozoans trypanosomes euglenoids ~80,000 named species radiolarians Shelled cells foraminiferans 7 groups prokaryotic ancestor ciliates Alveolates dinoflagellates Flagellated protozoans apicomplexans water molds Shelled cells diatoms Stramenopiles brown algae Alveolates red algae chlorophyte algaeGreen Stramenopiles charophyte algae Algae land plants Red & green algae amoebas Amoebozoans slime molds Amoebozoans fungi Fig. 22-2f, p. 352 choanoflagellates Choanoflagellates animals 5 Quick Quiz: Based on the cladogram on the previous slide, which group of protists is most closely related to land plants? A) Flagellated protozoans B) Shelled cells C) Alveolates D) Stramenopiles E) Red & Green Algae F) Ameobozoans G) Choanoflagellates 6 Flagellated Protozoans General characteristics Single-celled No cell wall One or more flagella Reproduce by binary fission 3 representative groups Anaerobic flagellates Trypanosomes Euglenoids 7 Flagellated Protozoans Anaerobic flagellates – live without oxygen Diplomonads E.g., Giardia lamblia Cysts can survive outside the body Giardia lamblia Parabasalids E.g, Trichomonas vaginalis Does not survive outside the body Cause of an STI Trichomonas vaginalis 8 Flagellated Protozoans Trypanosomes / Kinetoplastids Trypanosomes - parasites E.g., Trypanosoma brucei African sleeping sickness spread by tsetse fly (vector) Trypanosoma brucei 9 Flagellated Protozoans Euglenoids – varied group Predators, parasites, autotrophs Photosynthetic euglenoids have eyespots to detect light All euglenoids have contractile vacuoles Euglena gracilis 10 Quick Quiz: A flagellated protist that lives in environments without oxygen is a(n)… A) Anaerobic protozoan B) Trypanosome C) Euglenoid D) All of the above 11 Quick Quiz: Name an example of an anaerobic protozoan A) Giardia lamblia B) Euglena C) Trypanosoma brucei D) All of the above 12 Shelled Protozoans Foraminiferans (forams) Calcium carbonate shells Dead forams chalk & limestone Radiolarians Foraminiferan Silicate shells Air-filled vacuoles Radiolarians 13 Quick Quiz: A protist with a silicate (glass) shell that floats in the ocean would be a(n)… A) Euglenoid B) Foraminiferan C) Parabasalid D) Radiolarian E) Trypanosome 15 Alveolates General characteristics Layers of sacs under plasma membrane 3 representative groups Ciliates Dinoflagellates Apicomplexans 16 Ciliates General characteristics Heterotrophs Single-celled Ciliated Highly diverse group Reproduce by binary fission Example: Paramecium 17 Dinoflagellates General characteristics Single-celled Two flagella Reproduce by binary fission usually Can cause algal blooms, or “red tides” Karenia brevis 18 Apicomplexans (Sporozoans) General characteristics Parasitic – infect animals Example: Plasmodium falciparum Cause of malaria 19 Quick Quiz: Paramecium moves in the water because of the motion of its… A) Flagella B) Alveoli C) Cilia D) All of the above 20 Quick Quiz: Plasmodium falciparum causes malaria in people because… A) It pollutes water people drink B) It reproduces inside certain human cells C) It causes swelling of people’s airways D) All of the above 21 Stramenopiles General characteristics Grouped by molecular similarity Few common visible characteristics 3 representative groups Diatoms Brown algae Water molds 22 Diatoms General characteristics Single-celled OR colonial 2-part silica shell Usually reproduce asexually; occasionally reproduce sexually Source of diatomaceous earth 23 Brown algae General characteristics Multicellular Olive green, golden to dark brown Live in cooler water Alternation of generations Size range Giant kelp (30m) Microscopic filaments Macrocystis 24 Water molds General characteristics Colonial or single-celled Similar to fungi in some ways; distinct in others Cell walls made of cellulose, not chitin Filaments are made of diploid cells, not haploid Example: Saprolegnia Saprolegnia 25 Quick Quiz: Stramenopiles all share which of the following? A) Photosynthetic metabolism B) Multicellular organization C) Silica-based shells D) Molecular similarity but no common morphology 26 Red Algae General characteristics Most are multicellular Live in warm water Can live in deep water with little light Have a different kind of light-capturing molecule Antithamnion plumula 27 Green Algae General characteristics Single-celled or multicellular Similar to land plants Photosynthetic Chlorophylls a and b Volvox 2 representative groups Chlorophytes Charophyte algae Chara Ulva Codium fragilis 28 Quick Quiz: True or false: The algae are a monophyletic group. A) True B) False 29 Quick Quiz: Green algae are considered closest to land plants because… A) They are both green B) They both have the same chlorophyll molecules C) They both are multicellular 30 Amoebozoans General characteristics Lack a rigid shape Move by pseudopods 2 representative groups Amoebas Slime molds Ameoba proteus 31 Amoebas Entamoeba histolytica Pathogen Can form cysts Amoebic dysentery 32 Quick Quiz: True or false: Amoeboid protists are all formless blobs all the time. A) True B) False 33 Quick Quiz: True or false: Some amoeboids are multicellular organisms. A) True B) False 34 .
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