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Syncystidae
The Syncystidae are a family of parasitic alveolates in the phylum Apicomplexa. Species in this family infect insects (Aeshnidae). History This family was described by Schneider in 1886. Taxonomy One genus and two species ('' Syncystis aeshnae'', '' Syncystis mirabilis'') are currently recognised in this family.Tuzet O, Manier JF (1953) ''Syncystis aeschnae'' n.sp. Néogrégarine (Schizogrégarine, Léger, 1900) parasite des larves d'Aeschna. Ann Nat Sci Zool IIe ser 15:241-246 The type species is '' Syncystis mirabilis'' Schneider 1886. Lifecycle The development of these parasites is mostly intracellular. Merogony results in the formation of about 150 elongate, slender merozoites which become spheroidal as they differentiate into amoeboid or spheroidal gamonts. The gamonts associate in syzygy and subdivide into gametes. Fusion of the gametes leads to numerous zygotes within the gametocyst which is either spherical or bilobed. Numerous (30 to 150) oocysts are formed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syncystis Aeshnae
Syncystis is a genus of parasitic alveolates in the phylum Apicomplexa. Species in this family infect insects (Aeshnidae). History This genus was described by Schneider in 1886. Taxonomy Two species are currently recognised in this family.Tuzet O, Manier JF (1953) ''Syncystis aeschnae'' n.sp. Néogrégarine (Schizogrégarine, Léger, 1900) parasite des larves d'Aeschna. Ann Nat Sci Zool IIe ser 15:241-246 The type species is '' Syncystis mirabilis'' Schneider 1886. Lifecycle The development of these parasites is mostly intracellular. Merogony results in the formation of about 150 elongate, slender merozoites which become spheroidal as they differentiate into amoeboid or spheroidal gamonts. The gamonts associate in syzygy and subdivide into gametes. Fusion of the gametes leads to numerous zygotes within the gametocyst which is either spherical or bilobed. Numerous (30 to 150) oocyst Apicomplexans, a group of intracellular parasites, have life cycle stages that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syncystis Mirabilis
Syncystis is a genus of parasitic alveolates in the phylum Apicomplexa. Species in this family infect insects (Aeshnidae). History This genus was described by Schneider in 1886. Taxonomy Two species are currently recognised in this family.Tuzet O, Manier JF (1953) ''Syncystis aeschnae'' n.sp. Néogrégarine (Schizogrégarine, Léger, 1900) parasite des larves d'Aeschna. Ann Nat Sci Zool IIe ser 15:241-246 The type species is '' Syncystis mirabilis'' Schneider 1886. Lifecycle The development of these parasites is mostly intracellular. Merogony results in the formation of about 150 elongate, slender merozoites which become spheroidal as they differentiate into amoeboid or spheroidal gamonts. The gamonts associate in syzygy and subdivide into gametes. Fusion of the gametes leads to numerous zygotes within the gametocyst which is either spherical or bilobed. Numerous (30 to 150) oocyst Apicomplexans, a group of intracellular parasites, have life cycle stages that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neogregarinorida
The Neogregarinorida are an order of parasitic alveolates in the phylum Apicomplexa. Species in this order infect insects and are usually found in the fat body, hemolymph, hypodermis, intestine or Malpighian tubules. The most common site of infection is the fat body: many species are pathogenic for their hosts. The species in this order are predominantly intracellular parasites. Taxonomy Six families are in this order, with 13 genera. The type genus is '' Ophryocystis''. Two families (Ophryocystidae and Schizocystidae) belong to the suborder Schizogregarinina. They appear to have evolved from the Eugregarinorida. Merogony as part of the life cycle separates them from the Eugregarinorida and appears to have been derived as a secondary characteristic. A phylogenetic analysis of the small subunit RNA suggests ''Ophryocystis'' may actually be a eugregarine rather than a neogregarine. General characteristics * Merogony, gamogony and sporogony are present in all species * They ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syncystis
Syncystis is a genus of parasitic alveolates in the phylum Apicomplexa. Species in this family infect insects (Aeshnidae). History This genus was described by Schneider in 1886. Taxonomy Two species are currently recognised in this family.Tuzet O, Manier JF (1953) ''Syncystis aeschnae'' n.sp. Néogrégarine (Schizogrégarine, Léger, 1900) parasite des larves d'Aeschna. Ann Nat Sci Zool IIe ser 15:241-246 The type species is '' Syncystis mirabilis'' Schneider 1886. Lifecycle The development of these parasites is mostly intracellular. Merogony results in the formation of about 150 elongate, slender merozoites which become spheroidal as they differentiate into amoeboid or spheroidal gamonts. The gamonts associate in syzygy and subdivide into gametes. Fusion of the gametes leads to numerous zygotes within the gametocyst which is either spherical or bilobed. Numerous (30 to 150) oocysts are formed per gametocyst. The oocysts are navicular and have three or four spines ... [...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] |
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] |
Meiosis
Meiosis (; , since it is a reductional division) is a special type of cell division of germ cells in sexually-reproducing organisms that produces the gametes, such as sperm or egg cells. It involves two rounds of division that ultimately result in four cells with only one copy of each chromosome ( haploid). Additionally, prior to the division, genetic material from the paternal and maternal copies of each chromosome is crossed over, creating new combinations of code on each chromosome. Later on, during fertilisation, the haploid cells produced by meiosis from a male and female will fuse to create a cell with two copies of each chromosome again, the zygote. Errors in meiosis resulting in aneuploidy (an abnormal number of chromosomes) are the leading known cause of miscarriage and the most frequent genetic cause of developmental disabilities. In meiosis, DNA replication is followed by two rounds of cell division to produce four daughter cells, each with half the number of chr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Merozoite
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 org ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apicomplexan Life Cycle
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] |
