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- Diatoms - Encyclopedia. com
Diatoms belong to the taxonomic phylum Bacillariophyta There are approximately 10, 000 known diatom species Of all algae phyla, diatom species are the most numerous Diatoms frustules are used to differentiate species Diatom frustules are composed of very pure hydrated silica within a layer of organic, carbon containing material
- Bacillariophyta - Encyclopedia. com
Bacillariophyta A phylum of algae comprising the diatoms These marine or freshwater unicellular organisms have cell walls (frustules) composed of pectin impregnated with silica and consisting of two halves, one overlapping the other Diatoms are found in huge numbers in plankton and are important in the food chains of seas and rivers
- Diatom - Encyclopedia. com
Most diatoms are unicellular, but some are colonial or filamentous Most are photosynthetic, but some species lack chlorophyll and live heterotrophically among decaying marine algae Pennate (i e bilaterally symmetrical) diatoms occur in both freshwater and marine habitats; centric diatoms (i e radially symmetrical) occur predominantly as
- 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)
- Dinoflagellata - Encyclopedia. com
dinoflagellates A division (Dinoflagellata) of protists that are heterotrophs but closely allied to brown algae and diatoms (they are sometimes classified as algae) Many have brown or yellow chromoplasts containing xanthophyll and chlorophylls a and c; others are colourless Typically, dinoflagellates have two flagella, one propelling water to
- Protista - Encyclopedia. com
At this point, the diatom produces gametes that fuse with gametes from other diatoms to produce zygotes The zygotes develop into full sized diatoms that can begin asexual reproduction once more When diatoms die, their shells fall to the bottom of the ocean and form deposits called diatomaceous earth These deposits can be collected and used
- 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
- Decapoda (Crabs, Shrimps, and Lobsters) | Encyclopedia. com
The bay shrimp is known to scavenge opportunistically and will also eat diatoms, algae, and detritus reproductive biology Studies of closely related species of Crangon reveal that most individuals are protandric hermaphrodites (maturing first as males and then changing to female as they get larger) while some "primary females" remain the same
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