|
Marteilia
''Marteilia'' is a protozoan genus of organisms that are parasites of bivalves. It causes QX disease in Sydney rock oysters and Aber disease in European flat oysters. After being infected by ''Marteilia'', bivalves lose pigmentation in their visceral tissue and become emaciated (Carrasco, Green, & Itoh, 2015). History In the late 1960s and early 1970s, there was a huge decline in European flat oyster (''Ostrea edulis'') population in Brittany, France. This had a huge socioeconomic impact in Europe. '' Marteilia refringens'' was discovered to be the cause of this decline in oyster (Grizel et al., 1974). Around the same time, '' Marteilia sydneyi'' was also found to be causing mortalities in Sydney rock oyster (''Saccostrea glomerate'') in Australia (Perkins & Wolf, 1976). There has been some success in breeding strains of Sydney rock oyster that are resistant to Marteilia ('QX disease'). Morphology ''Marteilia'' has a very peculiar morphology. The outermost cell is the primar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marteilia Sydneyi
''Marteilia'' is a protozoan genus of organisms that are parasites of bivalves. It causes QX disease in Sydney rock oysters and Aber disease in European flat oysters. After being infected by ''Marteilia'', bivalves lose pigmentation in their visceral tissue and become emaciated (Carrasco, Green, & Itoh, 2015). History In the late 1960s and early 1970s, there was a huge decline in European flat oyster (''Ostrea edulis'') population in Brittany, France. This had a huge socioeconomic impact in Europe. '' Marteilia refringens'' was discovered to be the cause of this decline in oyster (Grizel et al., 1974). Around the same time, '' Marteilia sydneyi'' was also found to be causing mortalities in Sydney rock oyster (''Saccostrea glomerate'') in Australia (Perkins & Wolf, 1976). There has been some success in breeding strains of Sydney rock oyster that are resistant to Marteilia ('QX disease'). Morphology ''Marteilia'' has a very peculiar morphology. The outermost cell is the primary ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marteilia Refringens
''Marteilia'' is a protozoan genus of organisms that are parasites of bivalves. It causes QX disease in Sydney rock oysters and Aber disease in European flat oysters. After being infected by ''Marteilia'', bivalves lose pigmentation in their visceral tissue and become emaciated (Carrasco, Green, & Itoh, 2015). History In the late 1960s and early 1970s, there was a huge decline in European flat oyster (''Ostrea edulis'') population in Brittany, France. This had a huge socioeconomic impact in Europe. '' Marteilia refringens'' was discovered to be the cause of this decline in oyster (Grizel et al., 1974). Around the same time, ''Marteilia sydneyi'' was also found to be causing mortalities in Sydney rock oyster (''Saccostrea glomerate'') in Australia (Perkins & Wolf, 1976). There has been some success in breeding strains of Sydney rock oyster that are resistant to Marteilia ('QX disease'). Morphology ''Marteilia'' has a very peculiar morphology. The outermost cell is the primary cel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sydney Rock Oyster
''Saccostrea glomerata'', is an oyster species belonging to the family Ostreidae.MolluscaBase eds. (2022). MolluscaBase. Saccostrea Dollfus & Dautzenberg, 1920. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=138300 on 2022-04-27 It is endemic to Australia and New Zealand. In Australia, it is known as the Sydney rock oyster and is commercially farmed. In New Zealand, where the species is not farmed, it is known as the New Zealand rock oyster or Auckland oyster. The species is closely related to ''Saccostrea cucullata'', the hooded oyster, which is common on Indo-Pacific rocky shores. Sydney rock oysters are capable of tolerating a wide range of salinities (halotolerant). They are usually found in the intertidal zone to below the low-water mark. Taxonomy The Sydney rock oyster and New Zealand rock oyster have previously been classified as two separate species: ''Saccostrea commercialis'' and ''S. glomerata'', resp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascetosporea
The Ascetosporea are a group of eukaryotes that are parasites of animals, especially marine invertebrates. The two groups, the haplosporids and paramyxids, are not particularly similar morphologically, but consistently group together on molecular trees, which place them near the base of the Cercozoa. Both produce spores without the complex structures found in similar groups (such as polar filaments or tubules). Haplosporid spores have a single cell nucleus, nucleus and an opening at one end, covered with an internal diaphragm or a distinctive hinged lid. After emerging, it develops within the cells of its host, usually a marine Mollusca, mollusc or annelid, although some infect other groups or freshwater species. The trophic cell is generally multinucleated. Paramyxids develop within the digestive system of marine invertebrates, and undergo internal budding to produce multicellular spores. A 2009 study concluded that ''Haplosporidium'' species form a paraphyletic group and that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paramyxida
The Ascetosporea are a group of eukaryotes that are parasites of animals, especially marine invertebrates. The two groups, the haplosporids and paramyxids, are not particularly similar morphologically, but consistently group together on molecular trees, which place them near the base of the Cercozoa. Both produce spores without the complex structures found in similar groups (such as polar filaments or tubules). Haplosporid spores have a single nucleus and an opening at one end, covered with an internal diaphragm or a distinctive hinged lid. After emerging, it develops within the cells of its host, usually a marine mollusc or annelid, although some infect other groups or freshwater species. The trophic cell is generally multinucleated. Paramyxids develop within the digestive system of marine invertebrates, and undergo internal budding to produce multicellular spores. A 2009 study concluded that ''Haplosporidium'' species form a paraphyletic group and that the taxonomy of the hap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spore
In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, fungi and protozoa. Bacterial spores are not part of a sexual cycle, but are resistant structures used for survival under unfavourable conditions. Myxozoan spores release amoeboid infectious germs ("amoebulae") into their hosts for parasitic infection, but also reproduce within the hosts through the pairing of two nuclei within the plasmodium, which develops from the amoebula. In plants, spores are usually haploid and unicellular and are produced by meiosis in the sporangium of a diploid sporophyte. Under favourable conditions the spore can develop into a new organism using mitotic division, producing a multicellular gametophyte, which eventually goes on to produce gametes. Two gametes fuse to form a zygote which develops into a new s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tricellular
{{Short pages monitor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bicellular
{{Short pages monitor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitosis
In cell biology, mitosis () is a part of the cell cycle in which replicated chromosomes are separated into two new nuclei. Cell division by mitosis gives rise to genetically identical cells in which the total number of chromosomes is maintained. Therefore, mitosis is also known as equational division. In general, mitosis is preceded by S phase of interphase (during which DNA replication occurs) and is often followed by telophase and cytokinesis; which divides the cytoplasm, organelles and cell membrane of one cell into two new cells containing roughly equal shares of these cellular components. The different stages of mitosis altogether define the mitotic (M) phase of an animal cell cycle—the division of the mother cell into two daughter cells genetically identical to each other. The process of mitosis is divided into stages corresponding to the completion of one set of activities and the start of the next. These stages are preprophase (specific to plant cells), prophase ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
