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- Diatoms - Encyclopedia. com
Diatoms Algae are a very diverse group of simple, nucleated, plant-like aquatic organisms that are primary producers Primary producers are able to utilize photosynthesis to create organic molecules from sunlight, water , and carbon dioxide Ecologically vital, algae account for roughly half of photosynthetic production of organic material on earth in both freshwater and marine environments
- Diatom | Encyclopedia. com
diatom A microscopic alga, belonging to the division Bacillariophyta, in which the cell wall (frustule) is composed of silica and consists of two halves, one of which overlaps the other like the lid of a box Frustules are often delicately ornamented Most diatoms are unicellular, but some are colonial or filamentous Most are photosynthetic, but some species lack chlorophyll and live
- Algae - Encyclopedia. com
Diatoms are also the most abundant algae in the open ocean and responsible for about one-quarter of all the oxygen gas produced on the earth each year Diatom populations often bloom in lakes in the spring, providing a major food for zooplankton, forming the base of the aquatic food chain There are over one hundred thousand species of diatoms
- Protists - Encyclopedia. com
Diatoms store their energy as oils or carbohydrates The dinoflagellates are members of the phylum Dinoflagellata These organisms are unicellular autotrophs Their cell walls contain cellulose, creating thick, protective plates These plates contain two grooves at right angles to each other, each groove containing one flagellum
- pennate diatom | Encyclopedia. com
pennate diatom A diatom (Bacillariophyta) that has bilateral symmetry Some pennate diatoms are marine, others inhabit fresh water, some are planktonic (see PLANKTON), others live attached to a substrate Compare CENTRIC DIATOM
- Protozoa - Encyclopedia. com
The Amoeba, for example, is capable of detecting chemicals given off by potential food particles such as diatoms , algae, bacteria or other protozoa As the cell wall has no definite shape, the cytoplasm can extrude to form pseudopodia (Greek pseudes, "false"; pous, "foot") in various sizes and at any point of the cell surface
- Chrysophyta - Encyclopedia. com
Chrysophyta (krəsŏf´ətə), phylum (division) of unicellular marine or freshwater organisms of the kingdom Protista [1] consisting of the diatoms [2] (class Bacillariophyceae), the golden, or golden-brown, algae (class Chrysophyceae), and the yellow-green algae [3] (class Xanthophyceae)
- Protista - Encyclopedia. com
Protista (Protoctista) A kingdom in the domain Eucaryota that comprises single-celled, eukaryotic organisms (see eukaryote) that may resemble animals or plants Naked and shelled amoebas, foraminiferans, zooflagellates, ciliates, dinoflagellates, diatoms, and algae are protists In an earlier five-kingdom classification, Protista was ranked as a kingdom; later some multicellular organisms with
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