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Pedinellales
Pedinellales ( ICN) or Pedinellida (ICZN) is a group of single-celled algae found in both marine environments and freshwater. These are found in both freshwater and marine environments, and most genera are sessile, attached by posterior stalks. The flagellum is at the anterior of the cell, and the tentacles surround it, often capturing small prey drawn in by its current. The colored genera are '' Pedinella'', '' Apedinella'', '' Pseudopedinella'', and '' Mesopedinella''. Several more genera have lost their chloroplasts and feed entirely by phagocytosis. These are '' Parapedinella'', '' Actinomonas'', and '' Pteridomonas''. It also appears that certain heliozoa are actually derived pedinellids. ''Ciliophrys'' alternates between a mobile flagellate stage and a heliozoan feeding stage, where the body is contracted with extended axopods all over its surface, and the flagellum is curled up into a tight figure eight. The actinophryids, ''Actinophrys'' and ''Actinosphaerium'', exi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chrysophyceae
The Chrysophyceae, usually called chrysophytes, chrysomonads, golden-brown algae, or golden algae, are a large group of algae, found mostly in freshwater. Golden algae is also commonly used to refer to a single species, '' Prymnesium parvum'', which causes fish kills. The Chrysophyceae should not be confused with the Chrysophyta, which is a more ambiguous taxon. Although "chrysophytes" is the anglicization of "Chrysophyta", it generally refers to the Chrysophyceae. Members Originally they were taken to include all such forms of the diatoms and multicellular brown algae, but since then they have been divided into several different groups (e.g., Haptophyceae, Synurophyceae) based on pigmentation and cell structure. Some heterotrophic flagellates as the bicosoecids and choanoflagellates were sometimes seen as related to golden algae too. They are now usually restricted to a core group of closely related forms, distinguished primarily by the structure of the flagella in motile cel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apedinella
''Apedinella'', also called Pedinellophyceae, is a small group of heterokonts (stramenopelis) with one species, the ''Apedinella radians''. It is assigned to the class Dictyochophyceae and the order of Pedinellaceae. It is a single cell marine phytoflagellate algae with chloroplasts found in seas all over the world. Characteristics The ''Apedinella'' cells have an apple like shape with one flagellum, containing mastigonemes, emerging as the stem. The cell diameter is about 7,5-12 micrometres and the calculated volume is between 221 and 904 micrometres ^3. The cell has radical symmetry. Each side had 3 symmetrical chloroplasts with big pyrenoids, which are laying more towards the inner side of the cell. The dictyosome is located more posterior and the nucleus is in the centre of the cell. The cells have two kinds of scales: ovoid bodies and elongated spine-scales. The whole cell surface is covered in the ovoid bodies and the cell has six long and slender spine scales, which help ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heliozoea
Heliozoa, commonly known as sun-animalcules, are microbial eukaryotes (protists) with stiff arms (axopodia) radiating from their spherical bodies, which are responsible for their common name. The axopodia are microtubule-supported projections from the amoeboid cell body, and are variously used for capturing food, sensation, movement, and attachment. They are similar to Radiolaria, but they are distinguished from them by lacking central capsules and other complex skeletal elements, although some produce simple scales and spines. They may be found in both freshwater and marine environments. Classification Originally the heliozoa were treated together as a formal taxon Heliozoa or Heliozoea, with the rank of class or phylum, but it has been realised that they are polyphyletic, as the various orders show notable differences and are no longer believed to be descended from a single common ancestor. Instead, "heliozoa" is regarded as a descriptive term applying to various lines of prot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heliozoa
Heliozoa, commonly known as sun-animalcules, are microbial eukaryotes (protists) with stiff arms (Pseudopodia#Morphology, axopodia) radiating from their spherical bodies, which are responsible for their common name. The axopodia are microtubule-supported projections from the amoeboid cell body, and are variously used for capturing food, sensation, movement, and attachment. They are similar to Radiolaria, but they are distinguished from them by lacking central capsules and other complex skeletal elements, although some produce simple scales and spines. They may be found in both freshwater and marine biology, marine environments. Classification Originally the heliozoa were treated together as a formal taxon Heliozoa or Heliozoea, with the rank of class or phylum, but it has been realised that they are polyphyletic, as the various orders show notable differences and are no longer believed to be descended from a single common ancestor. Instead, "heliozoa" is regarded as a descriptive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protozoa
Protozoa (: protozoan or protozoon; alternative plural: protozoans) are a polyphyletic group of single-celled eukaryotes, either free-living or parasitic, that feed on organic matter such as other microorganisms or organic debris. Historically, protozoans were regarded as "one-celled animals". When first introduced by Georg Goldfuss, in 1818, the taxon Protozoa was erected as a class within the Animalia, with the word 'protozoa' meaning "first animals", because they often possess animal-like behaviours, such as motility and predation, and lack a cell wall, as found in plants and many algae. This classification remained widespread in the 19th and early 20th century, and even became elevated to a variety of higher ranks, including phylum, subkingdom, kingdom, and then sometimes included within the paraphyletic Protoctista or Protista. By the 1970s, it became usual to require that all taxa be monophyletic (derived from a common ancestor that would also be regarded as protozo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyphyletic
A polyphyletic group is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as Homoplasy, homoplasies, which are explained as a result of convergent evolution. The arrangement of the members of a polyphyletic group is called a polyphyly .. [Source for pronunciation.] It is contrasted with monophyly and paraphyly. For example, the biological characteristic of warm-bloodedness evolved separately in the ancestors of mammals and the ancestors of birds; "warm-blooded animals" is therefore a polyphyletic grouping. Other examples of polyphyletic groups are algae, C4 photosynthesis, C4 photosynthetic plants, and Xenarthra#Evolutionary relationships, edentates. Many taxonomists aim to avoid homoplasies in grouping taxa together, with a goal to identify and eliminate groups that are found to be polyphyletic. This is often the stimulus for major re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phagotrophic
Phagocytosis () is the process by which a cell uses its plasma membrane to engulf a large particle (≥ 0.5 μm), giving rise to an internal compartment called the phagosome. It is one type of endocytosis. A cell that performs phagocytosis is called a phagocyte. In a multicellular organism's immune system, phagocytosis is a major mechanism used to remove pathogens and cell debris. The ingested material is then digested in the phagosome. Bacteria, dead tissue cells, and small mineral particles are all examples of objects that may be phagocytized. Some protozoa use phagocytosis as means to obtain nutrients. The two main cells that do this are the Macrophages and the Neutrophils of the immune system. Where phagocytosis is used as a means of feeding and provides the organism part or all of its nourishment, it is called phagotrophy and is distinguished from osmotrophy, which is nutrition taking place by absorption. History The history of phagocytosis represents the scientific esta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Øjvind Moestrup
Øjvind Moestrup (born 15 December 1941) is a Danish aquatic botanist, working particularly with the classification of algae. He worked at the Botanical Institute at the University of Copenhagen and is a professor emeritus in the Department of Biology there. He published over 100 scientific papers. Moestrup received his doctorate in biology from the University of Copenhagen in 1983, and has worked with the Fishery Inspection Service of the Danish Ministry of Fisheries. His major areas of research include the taxonomy of planktonic algae, haptophytes, toxic diatoms and raphidophytes. Honours In 2012 Professor Moestrup received the Yasumoto AwardThe Yasumoto Award is the most prestigious award given in the harmful algal bloom field. for excellence in his lifetime dedicated work of research on the biology, taxonomy and ultrastructure of microalgae. The following have been named after him: * '' Gyrodinium moestrupii'' * '' Moestrupia'' * '' Ochromonas moestrupii'' * '' Platychrys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bicosoecaceae
Bicosoecaceae is a family of bicosoecids in the order Bicosoecida. The name of the type genus ''Bicosoeca'' described by James-Clark in 1866 is derived from Greek roots (, vase, bowl, plus , inhabit). The philologically preferable compound would be ''Bicoeca'', as "corrected" by Stein in 1878 and followed by most subsequent authors. However, according to the ICBN and ICZN The International Code of Zoological Nomenclature (ICZN) is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals. It is also informally known as the ICZN Code, for its formal author, t ..., the original spelling of the name cannot be considered incorrect and it must be used in its original form. References External links * * Bicosoecaceaeat WoRMS Bikosea Stramenopile families {{Heterokont-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
