The Protozoans Ciliates Amoeboid Protozoans Flagellated Protozoans 1 Kingdom Protozoa Kingdom Protozoa z Defining Characteristics – – – 2 All are unicellular eukaryotes What is a prokaryote? Many species are both heterotrophic and autotrophic simultaneously or at different stages of the lifecycle Kingdom Protozoa Eukaryote Cell Prokaryote Cell Adaptability z z Protozoans are ecologically important primary producers, consumers and as vital links in the food chain Humans are greatly effected by parasitic protozoans either directly or indirectly – Effects range from irritating - fatal z 5 Malaria (Plasmodium spp.) worldwide epidemic Kingdom Protozoa Reproduction z Asexual reproduction – Replication of chromosomes and the splitting of the parent into two or more parts – Binary fission Multiple fission Budding – – z Protozoans are problematic in their associations as colonial forms – 6 Through asexual reproduction protozoans are identical and could be considered multicellular Kingdom Protozoa Asexual Reproduction Amoeba Flagellate 7 Ciliate Kingdom Protozoa Classification Alveolate Protozoans Phylum Ciliophora Phylum Dinozoa Phylum Apicomplexa The Cercozoa (Amoeboid Protozoans) Phylum Foraminifera Phylum Radiozoa Phytoflagellated protozoans 8 Kingdom Protozoa Phylum Ciliophora z Defining characteristics – z 9 Body externally ciliated in at least some lifecycle stages Have the highest degree of subcellular specialization and are considered advanced protozoans Paramecium feces Kingdom Protozoa Cilia z Cilia – z 10 Hair-like structures by which the organism moves, collects food and senses their surroundings Cilia structure Fastest of all the protozoans Kingdom Protozoa Ciliate Biology z Oral groove z Cytostome z Cytoproct z Contractile vacuole Paramecium Ciliate Lifestyles z z z 12 65% of all ciliate species are free-living and mobile Some ciliates form colonial aggregations and have sessile habits Other ciliates have symbiotic relationships in invertebrates and vertebrates Vorticella Kingdom Protozoa Dinoflagellates (Phylum Dinozoa) z Know for bioluminescence and highly toxic red tides – z z 13 Dense aggregations produce saxitoxin killing fish and crustaceans Also contaminates shellfish causing diarrheic shellfish poisoning Some benthic dinoflagellates produce a neurotoxin that accumulates in tropical fish called Ciguatera Kingdom Protozoa Zooflagellated Protozoans Choanoflagellates 14 Kingdom Protozoa Malaria (Plasmodium) Phylum Apicomplexa (Sporozoa) z All members of this phylum are endoparasites – – – – 16 Includes Malaria (Plasmodium) Toxoplasma gondii Perkinsus spp. Pneumocystis carinii Kingdom Protozoa Amoeboid Protozoans z z 17 Contains 4 phyla: Foraminifera, Radiozoa, Amoebozoa, and Heliozoa Most reproduce asexually through binary fission z z z Characterized by pseudopodia Food is usually captured by phagocytosis Body types range from free flowing to rigid with skeletal supports Kingdom Protozoa Phagocytosis 18 Kingdom Protozoa Amebas and Humans 19 Kingdom Protozoa Class Foraminifera (Cercozoa) z Defining characteristics – 20 Individuals secrete multi-chambered tests, generally made of calcium carbonate (CaCo3) Foram. tests Kingdom Protozoa Foraminiferans z z z Extremely abundant, most are benthic and marine Feed on diatoms and algae, very slow movers Organisms are extremely common and form ooze – 21 White cliffs of Dover are foraminiferan tests Kingdom Protozoa Phylum Radiozoa (Cercozoa) z Defining characteristics – z 22 Body is divided into distinct zones separated by a perforated membrane or capsule Have pseudopodia supported with thin microtubules that give a spiny rayed appearance Kingdom Protozoa Radiolarians Have shells made of silicon dioxide that can be very intricate z Feed on diatoms and other phytoplankton z – z Benthic individuals move by use of pseudopodia – 23 Most species are planktonic Can occur in large concentrations that form ooze as well Kingdom Protozoa The Flagellated Protozoans z z Characterized by the possession of a definite body shape and the possession of one or more flagella Most species are free-living and mobile Noctiluca 24 Kingdom Protozoa Phytoflagellated Protozoans z z Have chlorophyll and obtain energy directly from the sunlight Some are strictly autotrophic or heterotrophic – z 25 Some are a combination of both Both the Euglena and the dinoflagellates are examples of phytoflagellated protozoans Kingdom Protozoa