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Chaetocerotaceae
Chaetocerotaceae is a diatom family ( Bacillariophyta). This family comprise the three genera ''Attheya'' T. West, ''Bacteriastrum'' Shadbolt and ''Chaetoceros'' Ehrenberg. ''Chaetoceros'' is perhaps the largest and most species rich genus of marine planktonic diatoms. The taxonomic status within Chaetocerotaceae at present is somewhat unclear. Description The cells have valves with long setae. Cells are often in unseparable chains, but may appear as solitary cells in some species. Chains are formed by fusion of silica between the setae. Endogenous resting spores are common and very different from normal vegetative Vegetative describes vegetation. Vegetative may also refer to: *Vegetative reproduction Vegetative reproduction (also known as vegetative propagation, vegetative multiplication or cloning) is any form of asexual reproduction occurring in ... cells. References {{Taxonbar, from=Q2947532 Coscinodiscophyceae Diatom families ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteriastrum
''Bacteriastrum'' is a genus of diatoms in family Chaetocerotaceae.Tomas, C. R., Hasle G. R., Syvertsen, E. E., Steidinger, K. A., Tangen, K., Throndsen, J., Heimdal, B. R., (1997). ''Identifying Marine Phytoplankton'', Academic Press. There are more than 30 described species in genus ''Bacteriastrum'', but many of these are not currently accepted, and new species are still added to the genus.Sarno, D., Zingone, A. & Marino, D. (1997). ''Bacteriastrum parallelum'' sp. nov., a new diatom from the Gulf of Naples, and new observations on ''B. furcatum'' (Chaetocerotaceae, Bacillariophyta). Phycologia 36: 257-266 The type species for the genus is '' Bacteriastrum furcatum'' Shadbolt. Description ''Bacteriastrum'' is a widely distributed marine, planktonic genus. This genus is often associated with ''Chaetoceros'' but differs in radial symmetry and fenestration of setae. The colonies tend to lie in girdle view, and the cells are separated by the curvature of the basal part of the set ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chaetoceros
''Chaetoceros'' is probably the largest genus of marine planktonic diatoms with approximately 400 species described, although many of these descriptions are no longer valid. It is often very difficult to distinguish between different ''Chaetoceros'' species. Several attempts have been made to restructure this large genus into subgenera and this work is still in progress.Tomas, C. R., Hasle G. R., Syvertsen, E. E., Steidinger, K. A., Tangen, K., Throndsen, J., Heimdal, B. R., (1997). ''Identifying Marine Phytoplankton'', Academic Press.Rines J. E. B., Theriot E. C., (2003). ''Systematics of Chaetocerotaceae (Bacillariophyceae). I. A phylogenetic analysis of the family'', Phycological research 51: 83–98. However, most of the effort to describe species has been focused in boreal areas, and the genus is cosmopolitan, so there are probably many tropical species still undescribed.J.E.B. Rines, P. Boonruang and E.C. Theriot., (2000).'' Chaetoceros phuketensis sp. nov. (Bacillario ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seta
In biology, setae (singular seta ; from the Latin word for "bristle") are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Annelid setae are stiff bristles present on the body. They help, for example, earthworms to attach to the surface and prevent backsliding during peristaltic motion. These hairs make it difficult to pull a worm straight from the ground. Setae in oligochaetes (a group including earthworms) are largely composed of chitin. They are classified according to the limb to which they are attached; for instance, notosetae are attached to notopodia; neurosetae to neuropodia. Crustaceans have mechano- and chemosensory setae. Setae are especially present on the mouthparts of crustaceans and can also be found on grooming limbs. In some cases, setae are modified into scale like structures. Setae on the legs of krill and other small crustaceans help them to gather phytoplankton. It captures them and allow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Attheya
''Attheya'' is a genus of small single celled diatoms. Some of these species were earlier regarded to belong to ''Chaetoceros'', or to '' Gonioceros'', the taxonomic status of some of these species are still debated.Crawford, R.M., Hinz, F. and Koschinski, P. 2000. The combination of ''Chaetoceros gaussii'' (Bacillariophyta) with ''Attheya''. Phycologia 39(3):238-244. Description They are distinguished morphologically from ''Chaetoceros'' by the structure of valve outgrowths or girdle bands. The girdle bands can only be seen with an electron microscope.Crawford, R. M., Gardner, C., Medlin, L. K. 1994. The genus ''Attheya''. I. A description of four new taxa, and the transfer of ''Gonioceros septentrionalis'' and ''G. armatus''. ''Diatom research''. 9:27-51. Resting spores are seldom observed. Vegetative cells tend to attach to different substrates, including other diatoms,Tomas, C. R., Hasle G. R., Syvertsen, E. E., Steidinger, K. A., Tangen, K., Throndsen, J., Heimdal, B. R., (19 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diatom
A diatom (New Latin, Neo-Latin ''diatoma''), "a cutting through, a severance", from el, διάτομος, diátomos, "cut in half, divided equally" from el, διατέμνω, diatémno, "to cut in twain". is any member of a large group comprising several Genus, genera of algae, specifically microalgae, found in the oceans, waterways and soils of the world. Living diatoms make up a significant portion of the Earth's Biomass (ecology), biomass: they generate about 20 to 50 percent of the oxygen produced on the planet each year, take in over 6.7 billion metric tons of silicon each year from the waters in which they live, and constitute nearly half of the organic material found in the oceans. The Protist shell, shells of dead diatoms can reach as much as a half-mile (800 m) deep on the ocean floor, and the entire Amazon basin is fertilized annually by 27 million tons of diatom shell dust transported by transatlantic winds from the African Sahara, much of it from the Bodélé Dep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. '' Panthera leo'' (lion) and '' Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants of an ancestral taxon are grouped together (i.e. phylogenetic analysis should c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Christian Gottfried Ehrenberg
Christian Gottfried Ehrenberg (19 April 1795 – 27 June 1876) was a German naturalist, zoologist, comparative anatomist, geologist, and microscopist. Ehrenberg was an evangelist and was considered to be of the most famous and productive scientists of his time. Early collections The son of a judge, Christian Gottfried Ehrenberg was born in Delitzsch, near Leipzig. He first studied theology at the University of Leipzig, then medicine and natural sciences in Berlin and became a friend of the famous explorer Alexander von Humboldt. In 1818, he completed his doctoral dissertation on fungi, ''Sylvae mycologicae Berolinenses.'' In 1820–1825, on a scientific expedition to the Middle East with his friend Wilhelm Hemprich, he collected thousands of specimens of plants and animals. He investigated parts of Egypt, the Libyan Desert, the Nile valley and the northern coasts of the Red Sea, where he made a special study of the corals. Subsequently, parts of Syria, Ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Valves
A valve is a device or natural object that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways. Valves are technically fittings, but are usually discussed as a separate category. In an open valve, fluid flows in a direction from higher pressure to lower pressure. The word is derived from the Latin ''valva'', the moving part of a door, in turn from ''volvere'', to turn, roll. The simplest, and very ancient, valve is simply a freely hinged flap which swings down to obstruct fluid (gas or liquid) flow in one direction, but is pushed up by the flow itself when the flow is moving in the opposite direction. This is called a check valve, as it prevents or "checks" the flow in one direction. Modern control valves may regulate pressure or flow downstream and operate on sophisticated automation systems. Valves have many uses, including controlling water for irrigation, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resting Spores
A resting spore is a resistant cell, used to survive adverse environmental conditions. Resting spore is a term commonly applied to both diatoms and fungi. In fungi A resting spore can be a spore created by fungi which is thickly encysted (has a thick cell wall) in order to survive through stressful times, such as drought. It protects the spore from biotic (microbial, fungal viral), as well as abiotic (wind, heat, xeric conditions) factors. Resting spores of a particular fungus are known create the phenomenon known as late potato blight. They can lie dormant within the soil of a field for decades until the right conditions occur for viability (plant host present, rain, fire etc.). In diatoms A similar resting spore life stage is also present in diatoms, and in such case, is also often referred to as the hypnospore. Importantly, the resting spore of marine diatoms is not an obligate stage of the life cycle, except in the minority of studied taxa, where spore production immediate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vegetation
Vegetation is an assemblage of plant species and the ground cover they provide. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic characteristics. It is broader than the term ''flora'' which refers to species composition. Perhaps the closest synonym is plant community, but ''vegetation'' can, and often does, refer to a wider range of spatial scales than that term does, including scales as large as the global. Primeval redwood forests, coastal mangrove stands, sphagnum bogs, desert soil crusts, roadside weed patches, wheat fields, cultivated gardens and lawns; all are encompassed by the term ''vegetation''. The vegetation type is defined by characteristic dominant species, or a common aspect of the assemblage, such as an elevation range or environmental commonality. The contemporary use of ''vegetation'' approximates that of ecologist Frederic Clements' term earth cov ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coscinodiscophyceae
The Coscinodiscophyceae are a class of diatoms. They are similar to the Centrales, a traditional, paraphyletic subdivision of the heterokont algae known as diatoms. The order is named for the shape of the cell wall#Diatom cell walls, cell walls (or valves or frustules) of centric diatoms, which are circular or ellipsoid in valve view. The valves often bear Symmetry (biology), radially symmetrical ornamental patterns that can appear as dots when viewed with an optical microscope. Some also bear spines on their valves, which may either increase cell surface area and reduce sinking, or act as a deterrent to zooplankton grazers. Unlike pennate diatoms, centric diatoms never have a raphe. In terms of cell cycle, vegetative reproduction, vegetative cells are diploid and undergo mitosis during normal cell division. In sexual species, oogamy, oogamous meiosis produces haploid gametes, either ovum, ova or sperm cells. These fuse to produce a zygote which expands in size to develop i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
