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Blastogregarinorina
''Blastogregarinorina'' is a suborder of parasitic alveolates of the phylum Apicomplexia Taxonomy This suborder currently has one family with one genus which contains one species '' Siedleckia caulleryi''. This species is found in marine polychaetes. History This suborder was described by Chatton and Villeneuve in 1936 Description A mucron is present Syzygy does not occur. The gamonts are composed of a single structure without septa: they lack both protomerites and deutomerites. Anisogamy — unequal sized gamonts — is present. Gamogony occurs with gamonts still attached to intestinal wall. The gametes bud off gamonts. Gametocysts are absent There is no sporocyst. The zygote A zygote (, ) is a eukaryotic cell formed by a fertilization event between two gametes. The zygote's genome is a combination of the DNA in each gamete, and contains all of the genetic information of a new individual organism. In multicell ... gives rise to 10–16 oocysts. Ref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eugregarinorida
The ''Eugregarinorida'' are the most large and diverse order of gregarines — parasitic protists belonging to the phylum Apicomplexa. Eugregarines are found in marine, freshwater and terrestrial habitats. These species possess large trophozoites that are significantly different in morphology and behavior from the sporozoites. This taxon contains most of the known gregarine species. These protozoa are common parasites of many invertebrates including insects and polychete worms. Taxonomy Eugregarinorida has three recognised suborders: Aseptatorina, Blastogregarinorina and Septatorina. The intestinal eugregarines are separated into septate — suborder Septatina — and aseptate — suborder Aseptatina — depending on whether the trophozoite is superficially divided by a transverse septum. The marine gregarines are the most poorly studied members of this order. The eugregarines have been classified into 27 families with ~244 genera, 14 of which have more than 25 species each. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siedleckiidae
''Siedleckiidae'' is a family of parasitic alveolates in the phylum Apicomplexa. Species in this family infect marine invertebrates. Taxonomy This family was created by Edouard Chatton and Felix Villeneuve in 1936. There is one genus recognised in this family - '' Siedleckia''. The type species is ''Siedleckia nematoides''. The taxonomic position of this family is unclear and it may be related to the gregarines or to the coccidians.Diakin A, Simdyanov TG, Paskerova G, Alesohin VV, Entzeroth R, Schrevel J, Valigurova A (2012) Phylogenetic study on early emerging apicomplexans with emphasis on genera ''Eleutheroschizon'' and ''Siedleckia''. In: X. české a slovenské parazitologické dny. Description The gamonts are elongated and flattened. They possess a smooth surface lacking any grooves or folds. The pellicle appears to be trilaminar and longitudinal microtubules lie deep to it. The parasite attaches to the host cell via mucron. Feeding mode is apparently by myzocyto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siedleckia
''Siedleckia'' are a genus of parasitic alveolates in the phylum Apicomplexa. Species in this genus infect marine invertebrates. Taxonomy This genus was described by Caullery and Mesnil in 1898. There are four species recognised in this genus. The type species is ''Siedleckia nematoides''. The taxonomic position of this genus is unclear and it may be related to the gregarines or to the coccidians.Diakin A, Simdyanov TG, Paskerova G, Alesohin VV, Entzeroth R, Schrevel J, Valigurova A (2012) Phylogenetic study on early emerging apicomplexans with emphasis on genera ''Eleutheroschizon'' and ''Siedleckia''. In: X. české a slovenské parazitologické dny. Description The gamonts are elongated and flattened. They possess a smooth surface lacking any grooves or folds. The pellicle appears to be trilaminar and longitudinal microtubules lie deep to it. The parasite attaches to the host cell via mucron A ''mucron'' is an attachment organelle found in archigregarines - an order ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siedleckia Caulleryi
''Siedleckia'' are a genus of parasitic alveolates in the phylum Apicomplexa. Species in this genus infect marine invertebrates. Taxonomy This genus was described by Caullery and Mesnil in 1898. There are four species recognised in this genus. The type species is ''Siedleckia nematoides''. The taxonomic position of this genus is unclear and it may be related to the gregarines or to the coccidians.Diakin A, Simdyanov TG, Paskerova G, Alesohin VV, Entzeroth R, Schrevel J, Valigurova A (2012) Phylogenetic study on early emerging apicomplexans with emphasis on genera ''Eleutheroschizon'' and ''Siedleckia''. In: X. české a slovenské parazitologické dny. Description The gamonts are elongated and flattened. They possess a smooth surface lacking any grooves or folds. The pellicle appears to be trilaminar and longitudinal microtubules lie deep to it. The parasite attaches to the host cell via mucron A ''mucron'' is an attachment organelle found in archigregarines - an order ... [...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] |
Oocyst
Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism is typified by a ''cellular variety'' with a distinct morphology and biochemistry. Not all apicomplexa develop all the following cellular varieties and division methods. This presentation is intended as an outline of a hypothetical generalised apicomplexan organism. Methods of asexual replication Apicomplexans (sporozoans) replicate via ways of multiple fission (also known as schizogony). These ways include , and , although the latter is sometimes referred to as schizogony, despite its general meaning. Merogony is an asexually reproductive process of apicomplexa. After infecting a host cell, a trophozoite ( see glossary below) increases in size while repeatedly replicating its nucleus and other organelles. During this process, the or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zygote
A zygote (, ) is a eukaryotic cell formed by a fertilization event between two gametes. The zygote's genome is a combination of the DNA in each gamete, and contains all of the genetic information of a new individual organism. In multicellular organisms, the zygote is the earliest developmental stage. In humans and most other anisogamous organisms, a zygote is formed when an egg cell and sperm cell come together to create a new unique organism. In single-celled organisms, the zygote can divide asexually by mitosis to produce identical offspring. German zoologists Oscar and Richard Hertwig made some of the first discoveries on animal zygote formation in the late 19th century. Humans In human fertilization, a released ovum (a haploid secondary oocyte with replicate chromosome copies) and a haploid sperm cell (male gamete) combine to form a single diploid cell called the zygote. Once the single sperm fuses with the oocyte, the latter completes the division of the second ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apicomplexa Lifecycle Stages
Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism is typified by a ''cellular variety'' with a distinct morphology and biochemistry. Not all apicomplexa develop all the following cellular varieties and division methods. This presentation is intended as an outline of a hypothetical generalised apicomplexan organism. Methods of asexual replication Apicomplexans (sporozoans) replicate via ways of multiple fission (also known as schizogony). These ways include , and , although the latter is sometimes referred to as schizogony, despite its general meaning. Merogony is an asexually reproductive process of apicomplexa. After infecting a host cell, a trophozoite ( see glossary below) increases in size while repeatedly replicating its nucleus and other organelles. During this process, the orga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamete
A gamete (; , ultimately ) is a haploid cell that fuses with another haploid cell during fertilization in organisms that reproduce sexually. Gametes are an organism's reproductive cells, also referred to as sex cells. In species that produce two morphologically distinct types of gametes, and in which each individual produces only one type, a female is any individual that produces the larger type of gamete—called an ovum— and a male produces the smaller type—called a sperm. Sperm cells or spermatozoa are small and motile due to the flagellum, a tail-shaped structure that allows the cell to propel and move. In contrast, each egg cell or ovum is relatively large and non-motile. In short a gamete is an egg cell (female gamete) or a sperm (male gamete). In animals, ova mature in the ovaries of females and sperm develop in the testes of males. During fertilization, a spermatozoon and ovum unite to form a new diploid organism. Gametes carry half the genetic information of an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamogony
Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism is typified by a ''cellular variety'' with a distinct morphology and biochemistry. Not all apicomplexa develop all the following cellular varieties and division methods. This presentation is intended as an outline of a hypothetical generalised apicomplexan organism. Methods of asexual replication Apicomplexans (sporozoans) replicate via ways of multiple fission (also known as schizogony). These ways include , and , although the latter is sometimes referred to as schizogony, despite its general meaning. Merogony is an asexually reproductive process of apicomplexa. After infecting a host cell, a trophozoite ( see glossary below) increases in size while repeatedly replicating its nucleus and other organelles. During this process, the or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
