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Kingdom Protista. Protists first appeared in the fossil records about 1.5 billion years ago. Demonstrate an important evolutionary advancement, a membrane bound nucleus. Contain organelles such as ribsomes, mitochondria, and lysosomes.
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Protists first appeared in the fossil records about 1.5 billion years ago. Demonstrate an important evolutionary advancement, a membrane bound nucleus. Contain organelles such as ribsomes, mitochondria, and lysosomes. These structures provide a more efficient method of using available nutrients. Members of the Kingdom Protista are the simplest of the eukaryotes.
Background • Protists can be unicellular, multicellular or colonial. • Reproduce sexually and asexually. • Require an aquatic environment. • Some move around and act like animals, others perform photosynthesis like plants, and still others seem to "think" they're fungi!
Why are They Important? • Autotrophic protists, like phytoplankton, produce a significant portion of the Earth’s oxygen. • Play an important role in the carbon cycle. • Important producers and consumers in food chains. • Act as a road map for evolution!
Phylum Sarcodina - Amoeba Thrive in fresh water, salt water and soil. Many are motile, with pseudopods used for locomotion. Few parasitic species found in animal intestines.
Phylum Ciliophora - Paramecium Most complex and advanced of the protozoans. Have hairlike structures called cilia which are used for movement and in feeding. Reproduce through binary fission and conjugation.
Phylum Mastigophora • Flagellates move by means of flagella and are found in salt and fresh water.Most are parasitic and cause disease in animals. • Asexual reproduction • Form cysts that allow them to be spread from host to host.
Phylum Sporozoa • Lack means of independent locomotion. • Exclusively parasitic. • Depend entirely upon the body fluids of their hosts for movement. • Have a spore like stage.
Phylum Chrysophyta - Diatoms • Fresh and salt water • Autotrophic, contain chlorophyll. • Many are encased in shells or skeletons.
Phylum Pyrrophyta - Dinoflagellates Autotrophs, contain chlorophyll and red pigments. Can contaminate shell fish.
Phylum Euglenophyta - Euglena Both heterotrophic and autotrophic.Have an eye spot which is sensitive to light.Reproduce asexually and asexually. Evolutionary link between plants and animals.
Assignment • How do moneran and protist cells differ? • What roles do protists play in ecosystems? • Copy and complete the following chart by placing a check mark in the appropriate column. chart