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Teliospores 0433
Teliospore (sometimes called teleutospore) is the thick-walled resting spore of some fungi ( rusts and smuts), from which the basidium arises. Development They develop in '' telia'' (sing. ''telium'' or ''teliosorus''). The telial host is the primary host in heteroecious rusts. The aecial host is the alternate host (look for pycnia and aecia). These terms apply when two hosts are required by a heteroecious rust fungus to complete its life cycle. Morphology Teliospores consist of one, two or more dikaryote cells. Teliospores are often dark-coloured and thick-walled, especially in species where they overwinter (acting as chlamydospores). Two-celled teliospores formerly defined the genus ''Puccinia''. Here the wall is particularly thick at the tip of the terminal cell which extends into a beak in some species. Teliospores consist of dikaryote cells. As the teliospore cells germinate, the nuclei undergo karyogamy and thereafter meiosis, giving rise to a four-celled basidium ... [...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] |
Germ Cells
Germ or germs may refer to: Science * Germ (microorganism), an informal word for a pathogen * Germ cell, cell that gives rise to the gametes of an organism that reproduces sexually * Germ layer, a primary layer of cells that forms during embryonic development * Cereal germ, the reproductive part of a cereal grain * Tooth germ, an aggregation of cells that eventually forms a tooth * Germ theory of disease, which states that some diseases are caused by microorganisms * Germ (mathematics), an object in a topological space that captures local properties Art and media Music * Germs (band), an American punk rock band * Germ (musician), a stage name of Tim Wright * Germ (rapper), an American rapper affiliated with Suicideboys and Pouya * "Germs" (song), by "Weird Al" Yankovic * ''The Germ'' (album), by Victim's Family Others * "Germs" (''Invader Zim''), an episode of ''Invader Zim'' * ''The Germ'' (periodical), a British art magazine published in 1850 * The Germs (comics ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spores
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 spo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ustilaginomycetes
Ustilaginomycetes is the class of true smut fungi. They are plant parasites with about 1400 recognised species in 70 genera. They have a simple septum with a septal pore cap, this is different from Agaricomycotina which has a dolipore septum with parenthoesome. The group is monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ... (has a common ancestor). References Ustilaginomycotina Fungal plant pathogens and diseases Fungus classes {{fungus-plant-disease-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urediniospore
Urediniospores (or uredospores) are thin-walled spores produced by the uredium, a stage in the life-cycle of rusts. Development ''Urediniospores'' develop in the uredium, generally on a leaf's under surface. Morphology *Urediniospores usually have two dikaryote nuclei within one cell. In mass they are usually pale brown in contrast to teliospores which are generally dark brown. See also *Chlamydospore *Urediniomycetes *Pycniospore *Aeciospore *Teliospore *Ustilaginomycetes Ustilaginomycetes is the class of true smut fungi. They are plant parasites with about 1400 recognised species in 70 genera. They have a simple septum with a septal pore cap, this is different from Agaricomycotina which has a dolipore septum with ... * Rust fungus: Spores References *C.J. Alexopolous, Charles W. Mims, M. Blackwell, ''Introductory Mycology, 4th ed.'' (John Wiley and Sons, Hoboken NJ, 2004) Germ cells Fungal morphology and anatomy Mycology {{Basidiomycota-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aeciospore
Aeciospores are one of several different types of spores formed by Rusts. They each have two nuclei and are typically seen in chain-like formations in the aecium. References Fungal morphology and anatomy {{mycology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pycniospore
Pycniospores are a type of spore in fungi. They are produced in special cup-like structures called pycnia or pynidia. Almost all fungi reproduce asexually with the production of spores. Spores may be colorless, green, yellow, orange, red, brown or black. Other types of spore ;Sporangiospores Sporangiospores (spore:spore, angion:sac) are spores formed inside the sporangium which is a spore sac. ;Conidia Conidia (singular: conidium) are spores produced at the tip of special branches called conidiophores. ;Oidia Oidia (singular: oidium). In several fungi, the hyphae is often divided into a large number of short pieces by transverse walls. Each piece is able to germinate into a new body. These pieces are called oidia (small egg). ;Chlamydospores Chlamydospore A chlamydospore is the thick-walled large resting spore of several kinds of fungi, including Ascomycota such as '' Candida'', Basidiomycota such as ''Panus'', and various Mortierellales species. It is the life-stage whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urediniomycetes
The Pucciniomycetes (formerly known as the Urediniomycetes) are a class (biology), class of fungi in the Pucciniomycotina subdivision of the Basidiomycota. The class contains 5 order (biology), orders, 21 family (biology), families, 190 genus, genera, and 8016 species. It includes several important Phytopathology, plant pathogens causing forms of fungal Rust (fungus), rust. Characteristics Pucciniomycetes develop no basidiocarp, karyogamy occurs in a thick-walled resting spore (teliospore), and meiosis occurs upon germination of teliospore. They have simple septal pores without membrane caps and disc-like Mitotic spindle, spindle Microtubule organizing center, pole bodies. Except for a few species, the basidium, basidia, when present, are transversally septate. Mannose is the major cell wall carbohydrate, glucose, fucose and rhamnose are the less prevalent neutral sugars and xylose is not present. References Basidiomycota classes Pucciniomycotina {{Basidiomycetes-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlamydospore
A chlamydospore is the thick-walled large resting spore of several kinds of fungi, including Ascomycota such as '' Candida'', Basidiomycota such as ''Panus'', and various Mortierellales species. It is the life-stage which survives in unfavourable conditions, such as dry or hot seasons. ''Fusarium oxysporum'' which causes the plant disease Fusarium wilt is one which forms chlamydospores in response to stresses like nutrient depletion. Mycelia of the pathogen can survive in this manner and germinate in favorable conditions. Chlamydospores are usually dark-coloured, spherical, and have a smooth (non-ornamented) surface. They are multicellular, with cells connected by pores in the septae between cells. Chlamydospores are a result of asexual reproduction (in which case they are conidia called chlamydoconidia) or sexual reproduction (rare). Teliospores are special kind of chlamydospores formed by rusts and smuts. File:Candida pseudohyphae, chlamydospores, blastospores.png, Pseudohy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basidiospore
A basidiospore is a reproductive spore produced by Basidiomycete fungi, a grouping that includes mushrooms, shelf fungi, rusts, and smuts. Basidiospores typically each contain one haploid nucleus that is the product of meiosis, and they are produced by specialized fungal cells called basidia. Typically, four basidiospores develop on appendages from each basidium, of which two are of one strain and the other two of its opposite strain. In gills under a cap of one common species, there exist millions of basidia. Some gilled mushrooms in the order Agaricales have the ability to release billions of spores. The puffball fungus ''Calvatia gigantea'' has been calculated to produce about five trillion basidiospores. Most basidiospores are forcibly discharged, and are thus considered ballistospores. These spores serve as the main air dispersal units for the fungi. The spores are released during periods of high humidity and generally have a night-time or pre-dawn peak concentration in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haploid
Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respectively, in each homologous chromosome pair, which chromosomes naturally exist as. Somatic cells, tissues, and individual organisms can be described according to the number of sets of chromosomes present (the "ploidy level"): monoploid (1 set), diploid (2 sets), triploid (3 sets), tetraploid (4 sets), pentaploid (5 sets), hexaploid (6 sets), heptaploid or septaploid (7 sets), etc. The generic term polyploid is often used to describe cells with three or more chromosome sets. Virtually all sexually reproducing organisms are made up of somatic cells that are diploid or greater, but ploidy level may vary widely between different organisms, between different tissues within the same organism, and at different stages in an organism's life cycle. Half ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
