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Nassula Consuming Strands Of Cyanobacteria
''Nassula'' is a genus of unicellular ciliates, belonging to the class Nassophorea. Like other members of the class, ''Nassula'' possesses a basket-like feeding apparatus (''nasse'', or ''cyrtos'') made up of cytopharyngeal rods (''nematodesmata''), which are themselves composed of closely packed microtubules. ''Nassula'' use this structure to ingest filamentous cyanobacteria, drawing individual strands of blue-green algae through the cytopharynx and into the body of the cell, where they are digested. As the algae are broken down, they can take on a variety of bright colours, which give ''Nassula'' a distinctive, variegated appearance under the microscope. Description The body is ovoid to elongate, and uniformly ciliated, with a single macronucleus and a partial hypostomial frange (''synhymenium'') running from the left side of the cell to the oral aperture. When food is scarce, members of the genus have the ability to become dormant by forming a microbial cyst. Excystment c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryota
Eukaryotes () are organisms whose Cell (biology), cells have a cell nucleus, nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the Three-domain system, three domains of life. Bacteria and Archaea (both prokaryotes) make up the other two domains. The eukaryotes are usually now regarded as having emerged in the Archaea or as a sister of the Asgard (archaea), Asgard archaea. This implies that there are only Two-domain system, two domains of life, Bacteria and Archaea, with eukaryotes incorporated among archaea. Eukaryotes represent a small minority of the number of organisms, but, due to their generally much larger size, their collective global biomass (ecology), biomass is estimated to be about equal to that of prokaryotes. Eukaryotes emerged approximately 2.3–1.8 billion years ago, during the Proterozoic eon, likely as Flagellated cell, flagellated phagotrophs. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
