What other group of protists has these ceratium

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What other group of protists has these?
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Ceratium Gonyaulax: Gonyaulax: an a an armoured dinoflagellate. Cell wall is subdivided into multiple polygonal vesicles filled with relatively thick cellulose plates
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A “naked” dinoflagellate. Cell wall does not have thickened cellulose armour plates.
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Dinoflagellates Mature dinoflagellates are haploid (1n) Reproduction Mostly asexual Reproduce by fission A few can reproduce sexually Gametes formed by mitosis (not meiosis) because the cells are already haploid. Gametes (1n) are motile Zygotes (2n) formed by fusion of gametes are also motile
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Dinoflagellates Ecology 90% are marine Some freshwater About 50% are photosynthetic; the rest are heterotrophs (parasites) Photosynthetic dinoflagellates are second only to diatoms as primary producers in coastal waters. May be free-living or symbiotic Zooxanthellae are vital to the growth and survival of coral reefs
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Zooxanthellae Symbiotic dinoflagellates found in many marine invertebrates Sponges, corals, jellyfish, Hydra, Tridacnid clams and flatworms Also found within protists, such as ciliates, foraminiferans, and colonial radiolarians.
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Zooxanthellae Zooxanthellae
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Zooxanthellae Mutualism Host organism ingests the dinoflagellate and incorporate it into its own tissues without harming it. Dinoflagellate divides repeatedly, and begins to manufacture carbohydrates which are provided to the host. Many corals get all their food from the zooxanthellae; build reefs much faster with the dinoflagellates present in their tissues.
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Coral Bleaching = loss of zooxanthellae Coral Bleaching = loss of zooxanthellae
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Bioluminescence Some dinoflagellates are capable of producing light - bioluminescence Molecules made by the organism produce light in a chemical reaction. Luciferin and luciferase Same reaction that occurs in fireflies
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Health Issues Many dinoflagellates produce neurotoxins Poisons that injure the nerves of marine life that feed on the dinoflagellates May cause massive kills of fish and shellfish, as well as other forms of marine life. If animals containing these toxins are eaten by humans, the result may be illness or even death. Neurotoxins affect muscle function, preventing normal transmission of electrochemical messages from the nerves to the muscles by interfering with the movement of sodium ions through the cellular membranes
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Health Issues These toxins in the water can blow inland in sea spray and cause temporary health problems for people who live near the coast. The toxin from Gonyaulax catenella is so toxic that an aspirin sized tablet of the poison could kill 35 people; it is one of the strongest known poisons
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Neurotoxins Saxitoxin - most common dinoflagellate toxin 100,000 times more potent than cocaine Found in North American shellfish from Alaska to Mexico, and from Newfoundland to Florida Brevitoxin Causes fish kills
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