Transcript Eukarya
Eukarya • Eukarya includes all organisms with eukaryotic cells • Examples: – plants – animals – fungi – algae – single-celled animal-like protozoa Protists • Eukaryotic; but comprises its own Kingdom Protista – Algae - aquatic, photosynthetic organisms – Diatoms – Dinoflagellates – Protozoans – Foraminiferans, Radiolarians, Ciliates • Single and multi-cellular Unicellular Algae • • • Green Algae – Mostly freshwater and terrestrial – 10% of species are marine Brown Algae – Almost all species are marine – Sargassum (Sargasso seaweed) – Macrocystis (Giant Kelp) • plants grow up to 300 ft • can grow 20”/day • form kelp beds or kelp forests • Harvested for Algin (used in cosmetics and ice cream). Red Algae – Agar and carrageenan: gelling and thickening agents Diatoms • Extremely diverse and distinct members of marine phytoplankton – Unicellular • Diatom structure – Enclosed in a box-shaped organic cell wall with silica (SiO2), called a frustule – Holes in cell wall allow cholorplast to capture light and dissolved gases to enter. Dinoflagellates – Unicellular protists with 2 flagella (used for motility) – Globular, plated outer “shell” that is made of cellulose – Photosynthetic, but also can absorb nutrients – Most are planktonic (primary producers) – Can be bioluminescent – Bioluminescent Bay, Puerto Rico (pg. 97) • Red tides – produce toxin in water when in Harmful Algal Blooms (HABs) Amoeboid Protozoans • Unicellular Protists • All have an organelle called a pseudopod—an extension of the cell surface that can change shape and is used for locomotion and food capture • Are heterotrophs consuming bacteria and other small organisms Amoeboid Protozoans Amoeboid Protozoans • Major Protozoans: – Foraminiferans – Radiolarians – Ciliates Amoeboid Protozoans • Foraminiferans (forams) – have branched pseudopods that form elaborate, net-like structures used to: • snare prey • crawl • reduce sinking rate (pelagic) – consume bacteria and diatoms – some harbor symbiotic green and red algae and zooxanthellae – Have shell (test) made from CaCO3 – Bottom of the ocean (benthic) Foraminiferans Foraminiferans • White Cliffs of Dover Radiolarians • • • • • Unicellular protists Planktonic (primary producers) Shells make of silica (glass) Contains a needle-like pseudopodia Dead remains cover large portions of the ocean bottom as radiolarian ooze. Radiolarians Ciliates • Ciliates – protozoans that have cilia (hair-like growths) for locomotion and for gathering food • membranelles—tufts or long rows of fused adjacent cilia • Heterotrophs – cytostome—an organelle serving as a permanent site for phagocytosis of food – planktonic major links in marine food chains – form symbiotic and parasitic relationships – Paramecium Ciliates Fungi • General features of fungi – eukaryotes with cell walls of chitin – filamentous fungi grow into long, multi-cellular filaments called hyphae that can branch to produce a tangled mass called a mycelium – Important to marine ecosystems as heterotrophic decomposers that recycle organic material Maritime Lichens • Lichens: mutualistic associations between a fungus and an alga – fungi are usually ascomycotes – algae are usually green or blue-green bacteria • The fungus provides attachment, general structure, minerals, moisture • The alga produces organic matter through photosynthesis Marine Viruses • Viruses are diverse and are more abundant than any other organism in the sea • Have significance for marine food webs, population biology and diseases of marine organisms • Viruses of marine eukaryotic hosts first reported in the 1970s Biodiversity and Distribution of Marine Viruses • 10 times more abundant than marine prokaryotes, may reach 1010 virons per liter of seawater, 1013 per kilogram of sediment • Estimated 100 to 10,000 genotypes • Most planktonic viruses are icosahdral or binal bacteriophages (“bacteria eaters”) with lytic life cycles • Sediment viruses are typically helical and lysogenic Marine Microbes • http://www.youtube.com/watch?v=1TmHlcM DIOQ