2 Protozoans Includes forams and radiolarians Found on surface and in bottom sedimentsUnicellularAnimal likeKingdom ProtistaSubdivided into 3 phyla:CiliophoraZoomastiginaSarcodina
3 Ciliophora Largest group Most free swimming, some attached to substrateMove by beating microscopic ciliaFresh and salt water
4 Sarcodina Forams, radiolarians, and amoebas Live on surface of substratesMove and eat using pseudopods“amoeboid movement”
5 Zoomastigina Animal like protists Move using a flagella Live in freshwater, saltwater, and as parasites within other organisms
6 Life Functions of Protozoans All life functions carried out within 1 cell!Ingestion – getting food inDigestion – breaking food downRespiration – food to energy (ATP)Transport – gas exchangeWater balance/excretionSensitivity – responding to stimulireproduction
8 Ingestion and Digestion VorticellaFood is swept toward “mouth” oral groove by moving its ring of ciliaFood particles enter food vacuoles, where they are broken down.Intracellular digestion – inside a cell
9 Respiration Converting food (sugars) into energy (ATP) using oxygen Occurs in the mitochondriaOxygen + Glucose -> Water + Carbon Dioxide +36 ATPVorticella uses ATP to contract its stalk
10 Transport Oxygen and Carbon Dioxide diffuse across the cell membrane Oxygen diffuses INCarbon Dioxide diffuses OUTInside the cell food vacuoles move around and distribute nutrients
11 Water Balance and Secretion Water moves into aquatic organisms like Vorticella through osmosisEventually they would burst, but…Excess water is pumped out through the Contractile VacuoleExcretory Vacuole – pumps out liquid wasteHelps maintain homeostasis (a stable internal environment)
12 Sensitivity Ability of an organism to respond to environmental stimuli VorticellaResponds to touch by contracting its stalk into a coilAvoidance reaction to stimuli that may be harmfulAlso contracts spontaneously
13 Reproduction Asexual reproduction Binary fission – division of prokaryotic cell into 2 identical cells
14 Sexual reproduction Conjugation 2 parent protozoans exchange parts of their micronuclei when they come in contact (exchange genetic material)Increases genetic variationBinary fission then occurs, but with unique offspring.
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