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- Radiolarian | Marine Protists, Plankton, Microscopic | Britannica
Radiolarian, any protozoan of the class Polycystinea (superclass Actinopoda), found in the upper layers of all oceans Radiolarians, which are mostly spherically symmetrical, are known for their complex and beautifully sculptured, though minute, skeletons, referred to as tests Usually composed of
- Introduction to the Radiolaria - University of California Museum of . . .
Radiolaria can range anywhere from 30 microns to 2 mm in diameter Their skeletons tend to have arm-like extensions that resemble spikes, which are used both to increase surface area for buoyancy and to capture prey Most radiolarians are planktonic, and get around by coasting along ocean currents Most are somewhat spherical, but there exist a
- Diversity and ecology of Radiolaria in modern oceans - PMC
Diversity of the different extant Radiolaria orders A–B Acantharia: Lithoptera fenestra and Amphilonche elongata C–D Taxopodida: Sticholonche zanclea (C: live specimen; D: scanning electron microscopy image) E–F Polycystine ‐ Spumellaria: Diplosphaera spinosa and Euchitonia elegans G–H Polycystine ‐ Nassellaria: Pteroscenium sp and Plectaniscus sp
- Radiolarians: Microscopic Marine Mysteries | AMNH
Of the reported 15,000 living and fossil species of radiolaria, some 800 to 1,000 species are currently known to inhabit the oceans, where they play an important role in Earth’s carbon-oxygen cycle Like diatoms, single-celled algae that also form silica skeletons, radiolarians sink after death, trapping atmospheric carbon in the sediment of
- Radiolaria. org
Radiolaria are holoplanktonic protozoa widely distributed in the oceans They occur throughout the water column from near surface to hundreds of meters depth As with many planktonic organisms, their abundance in a geographical region is related to quality of the water mass, including such variables as temperature, salinity, productivity, and
- Radiolaria - Geology is the Way
Radiolaria Radiolarians are single-celled protozoa, measuring less than 0 1 - 0 2 mm in diameter, that produce intricate shells (skeletons) of amorphous silica They float as part of the zooplankton in the first 200 meters of water in the Earth's oceans (photic zone) They are mostly heterotrop
- Radiolaria - New World Encyclopedia
Radiolaria is a diverse grouping of amoeboid protozoa that produce intricate mineral skeletons, typically with a central capsule of cytoplasm separating the cell into inner and outer cytoplasmic portions, called endoplasm (with nuclei) and ectoplasm (or extracapsulum) As protozoans, radiolarians are tiny, single-celled eukaryotes, and as ameboids they move or feed by temporary projections
- Biology and Ecology of Radiolaria - SpringerLink
Radiolaria are holoplanktonic amoeboid protists with skeletons made of opaline silica (SiO 2 nH 2 O) or strontium sulfate (SrSO 4) (Fig 8 2) Their size ranges from tens to several hundreds of micrometers Radiolaria possess a common cytological structure of double-layered cytoplasm (endoplasm and ectoplasm) and pseudopodia (Figs 8 2 and 8 3
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