Ploidy ( / ˈ p l ɔɪ d i / ) is the number of complete sets of chromosomes in a cell , and hence the number of possible alleles for autosomal and pseudoautosomal genes . Here sets of chromosomes refers to the number of maternal and paternal chromosome copies, respectively, in each homologous chromosome pair—the form in which chromosomes naturally exist. 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 sets of chromosomes.
66-450: Udval is a Mongolian female name that means Aquilegia . Notable people with the name include: Natsagiin Udval (born 1954), Mongolian politician Sonomyn Udval (1921–1991) Mongolian politician and writer Tsogkhuu Udval (born 1994), Mongolian ju-jitsu practitioner [REDACTED] Name list This page or section lists people that share
132-611: A geometer moth , also uses columbine as a larval food plant. The larvae of the Papaipema leucostigma also feed on columbine. Plants in the genus Aquilegia are a major food source for Bombus hortorum , a species of bumblebee. Specifically, they have been found to forage on species of Aquilegia vulgaris in Belgium and Aquilegia chrysantha in North America and Belgium. The bees do not show any preference in color of
198-535: A ploidy series , featuring diploid ( X. tropicalis , 2n=20), tetraploid ( X. laevis , 4n=36), octaploid ( X. wittei , 8n=72), and dodecaploid ( X. ruwenzoriensis , 12n=108) species. Over evolutionary time scales in which chromosomal polymorphisms accumulate, these changes become less apparent by karyotype – for example, humans are generally regarded as diploid, but the 2R hypothesis has confirmed two rounds of whole genome duplication in early vertebrate ancestors. Ploidy can also vary between individuals of
264-417: A syncytium , though usually the ploidy of each nucleus is described individually. For example, a fungal dikaryon with two separate haploid nuclei is distinguished from a diploid cell in which the chromosomes share a nucleus and can be shuffled together. It is possible on rare occasions for ploidy to increase in the germline , which can result in polyploid offspring and ultimately polyploid species. This
330-675: A zygote with n pairs of chromosomes, i.e. 2 n chromosomes in total. The chromosomes in each pair, one of which comes from the sperm and one from the egg, are said to be homologous . Cells and organisms with pairs of homologous chromosomes are called diploid. For example, most animals are diploid and produce haploid gametes. During meiosis , sex cell precursors have their number of chromosomes halved by randomly "choosing" one member of each pair of chromosomes, resulting in haploid gametes. Because homologous chromosomes usually differ genetically, gametes usually differ genetically from one another. All plants and many fungi and algae switch between
396-467: A chromosome copy number of 1 to 4, and that number is commonly fractional, counting portions of the chromosome partly replicated at a given time. This is because under exponential growth conditions the cells are able to replicate their DNA faster than they can divide. In ciliates, the macronucleus is called ampliploid , because only part of the genome is amplified. Mixoploidy is the case where two cell lines, one diploid and one polyploid, coexist within
462-424: A germ cell with an uneven number of chromosomes undergoes meiosis, the chromosomes cannot be evenly divided between the daughter cells, resulting in aneuploid gametes. Triploid organisms, for instance, are usually sterile. Because of this, triploidy is commonly exploited in agriculture to produce seedless fruit such as bananas and watermelons. If the fertilization of human gametes results in three sets of chromosomes,
528-629: A haploid and a diploid state, with one of the stages emphasized over the other. This is called alternation of generations . Most fungi and algae are haploid during the principal stage of their life cycle, as are some primitive plants like mosses . More recently evolved plants, like the gymnosperms and angiosperms , spend the majority of their life cycle in the diploid stage. Most animals are diploid, but male bees , wasps , and ants are haploid organisms because they develop from unfertilized, haploid eggs, while females (workers and queens) are diploid, making their system haplodiploid . In some cases there
594-451: A number of chromosomes that is an exact multiple of the number of chromosomes in a normal gamete; and having any other number, respectively. For example, a person with Turner syndrome may be missing one sex chromosome (X or Y), resulting in a (45,X) karyotype instead of the usual (46,XX) or (46,XY). This is a type of aneuploidy and cells from the person may be said to be aneuploid with a (diploid) chromosome complement of 45. The term ploidy
660-425: A process called endoreduplication , where duplication of the genome occurs without mitosis (cell division). The extreme in polyploidy occurs in the fern genus Ophioglossum , the adder's-tongues, in which polyploidy results in chromosome counts in the hundreds, or, in at least one case, well over one thousand. It is possible for polyploid organisms to revert to lower ploidy by haploidisation . Polyploidy
726-672: A ring of staminodia around the base of the stigma, which may help protect against insects. Chromosome number is x=7. Columbines are closely related to plants in the genera Actaea (baneberries) and Aconitum (wolfsbanes/monkshoods), which like Aquilegia produce cardiogenic toxins . They are used as food plants by some Lepidoptera (butterfly and moth) caterpillars . These are mainly of noctuid moths – noted for feeding on many poisonous plants without harm – such as cabbage moth ( Mamestra brassicae ), dot moth ( Melanchra persicariae ) and mouse moth ( Amphipyra tragopoginis ). The engrailed ( Ectropis crepuscularia ),
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#1732781174102792-401: A single nucleus rather than in the cell as a whole. Because in most situations there is only one nucleus per cell, it is commonplace to speak of the ploidy of a cell, but in cases in which there is more than one nucleus per cell, more specific definitions are required when ploidy is discussed. Authors may at times report the total combined ploidy of all nuclei present within the cell membrane of
858-437: A single chromosome and diploid individuals have two chromosomes. In Entamoeba , the ploidy level varies from 4 n to 40 n in a single population. Alternation of generations occurs in most plants, with individuals "alternating" ploidy level between different stages of their sexual life cycle. In large multicellular organisms, variations in ploidy level between different tissues, organs, or cell lineages are common. Because
924-495: A single copy of each chromosome – that is, one and only one set of chromosomes. In this case, the nucleus of a eukaryotic cell is said to be haploid only if it has a single set of chromosomes , each one not being part of a pair. By extension a cell may be called haploid if its nucleus has one set of chromosomes, and an organism may be called haploid if its body cells (somatic cells) have one set of chromosomes per cell. By this definition haploid therefore would not be used to refer to
990-484: A single parent, without the involvement of gametes and fertilization, and all the offspring are genetically identical to each other and to the parent, including in chromosome number. The parents of these vegetative clones may still be capable of producing haploid gametes in preparation for sexual reproduction, but these gametes are not used to create the vegetative offspring by this route. Some eukaryotic genome-scale or genome size databases and other sources which may list
1056-463: A treatment for ulcers . However, the medical use of this plant is better avoided due to its high toxicity; columbine poisonings may be fatal. An acute toxicity test in mice has demonstrated that ethanol extract mixed with isocytisoside , the main flavonoid compound from the leaves and stems of Aquilegia vulgaris , can be classified as non-toxic, since a dose of 3000 mg/kg did not cause mortality. The Colorado blue columbine ( A. coerulea )
1122-490: Is 24. The monoploid number equals the total chromosome number divided by the ploidy level of the somatic cells: 48 chromosomes in total divided by a ploidy level of 4 equals a monoploid number of 12. Hence, the monoploid number (12) and haploid number (24) are distinct in this example. However, commercial potato crops (as well as many other crop plants) are commonly propagated vegetatively (by asexual reproduction through mitosis), in which case new individuals are produced from
1188-402: Is 7. The gametes of common wheat are considered to be haploid, since they contain half the genetic information of somatic cells, but they are not monoploid, as they still contain three complete sets of chromosomes ( n = 3 x ). In the case of wheat, the origin of its haploid number of 21 chromosomes from three sets of 7 chromosomes can be demonstrated. In many other organisms, although
1254-519: Is a back-formation from haploidy and diploidy . "Ploid" is a combination of Ancient Greek -πλόος (-plóos, "-fold") and -ειδής (- eidḗs ), from εἶδος ( eîdos , "form, likeness"). The principal meaning of the Greek word ᾰ̔πλόος (haplóos) is "single", from ἁ- (ha-, "one, same"). διπλόος ( diplóos ) means "duplex" or "two-fold". Diploid therefore means "duplex-shaped" (compare "humanoid", "human-shaped"). Polish-German botanist Eduard Strasburger coined
1320-764: Is a genus of about 130 species of perennial plants that are found in meadows , woodlands , and at higher elevations throughout the Northern Hemisphere, known for the spurred petals of their flowers . The genus name Aquilegia comes from the Latin "Aquila", or "eagle"; this is in obvious reference to the spurred, "hook" shapes within the blooms, that many gardeners say resemble an eagle's talons. Perennial herbs , with woody, erect stock, roots forming thick rhizomes . The basal leaves are compound, 1–3 ternate , blades 3-lobed -partite, and lobes lobulate and obtuse . The cauline leaves are similar to
1386-413: Is a characteristic of the bacterium Deinococcus radiodurans and of the archaeon Halobacterium salinarum . These two species are highly resistant to ionizing radiation and desiccation , conditions that induce DNA double-strand breaks. This resistance appears to be due to efficient homologous recombinational repair. Depending on growth conditions, prokaryotes such as bacteria may have
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#17327811741021452-412: Is an important evolutionary mechanism in both plants and animals and is known as a primary driver of speciation . As a result, it may become desirable to distinguish between the ploidy of a species or variety as it presently breeds and that of an ancestor. The number of chromosomes in the ancestral (non-homologous) set is called the monoploid number ( x ), and is distinct from the haploid number ( n ) in
1518-462: Is associated with a 14% lower risk of being endangered, and a 20% greater chance of being invasive. Polyploidy may be associated with increased vigor and adaptability. Some studies suggest that selection is more likely to favor diploidy in host species and haploidy in parasite species. However, polyploidization is associated with an increase in transposable element content and relaxed purifying selection on recessive deleterious alleles. When
1584-525: Is evidence that the n chromosomes in a haploid set have resulted from duplications of an originally smaller set of chromosomes. This "base" number – the number of apparently originally unique chromosomes in a haploid set – is called the monoploid number , also known as basic or cardinal number , or fundamental number . As an example, the chromosomes of common wheat are believed to be derived from three different ancestral species, each of which had 7 chromosomes in its haploid gametes. The monoploid number
1650-471: Is faster than diploid under high nutrient conditions. The NLH is also tested in haploid, diploid, and polyploid fungi by Gerstein et al. 2017. This result is also more complex: On the one hand, under phosphorus and other nutrient limitation, lower ploidy is selected as expected. However under normal nutrient levels or under limitation of only nitrogen , higher ploidy was selected. Thus the NLH – and more generally,
1716-577: Is suggested to have driven these changes in nectar spur length. It was shown that this spur length diversity is achieved solely through changing cell shape, not cell number or cell size. This suggests that a simple microscopic change can result in a dramatic evolutionarily relevant morphological change. 130 columbine species are accepted. Chromosome number 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
1782-526: Is the official state flower of Colorado (see also Columbine, Colorado ). It is also used as a symbol of the former city of Scarborough in the Canadian province of Ontario. Columbines have been important in the study of evolution . It was found that the Sierra columbine ( A. pubescens ) and crimson columbine ( A. formosa ) each has adapted specifically to a pollinator . Bees and hummingbirds are
1848-572: Is the simplest to illustrate in diagrams of genetics concepts. But this definition also allows for haploid gametes with more than one set of chromosomes. As given above, gametes are by definition haploid, regardless of the actual number of sets of chromosomes they contain. An organism whose somatic cells are tetraploid (four sets of chromosomes), for example, will produce gametes by meiosis that contain two sets of chromosomes. These gametes might still be called haploid even though they are numerically diploid. An alternative usage defines "haploid" as having
1914-426: Is the state in which the chromosomes are paired and can undergo meiosis. The zygoid state of a species may be diploid or polyploid. In the azygoid state the chromosomes are unpaired. It may be the natural state of some asexual species or may occur after meiosis. In diploid organisms the azygoid state is monoploid. (See below for dihaploidy.) In the strictest sense, ploidy refers to the number of sets of chromosomes in
1980-731: Is the state where all cells have multiple sets of chromosomes beyond the basic set, usually 3 or more. Specific terms are triploid (3 sets), tetraploid (4 sets), pentaploid (5 sets), hexaploid (6 sets), heptaploid or septaploid (7 sets), octoploid (8 sets), nonaploid (9 sets), decaploid (10 sets), undecaploid (11 sets), dodecaploid (12 sets), tridecaploid (13 sets), tetradecaploid (14 sets), etc. Some higher ploidies include hexadecaploid (16 sets), dotriacontaploid (32 sets), and tetrahexacontaploid (64 sets), though Greek terminology may be set aside for readability in cases of higher ploidy (such as "16-ploid"). Polytene chromosomes of plants and fruit flies can be 1024-ploid. Ploidy of systems such as
2046-402: Is thus 7 and the haploid number is 3 × 7 = 21. In general n is a multiple of x . The somatic cells in a wheat plant have six sets of 7 chromosomes: three sets from the egg and three sets from the sperm which fused to form the plant, giving a total of 42 chromosomes. As a formula, for wheat 2 n = 6 x = 42, so that the haploid number n is 21 and the monoploid number x
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2112-417: Is well established in this original sense, but it has also been used for doubled monoploids or doubled haploids , which are homozygous and used for genetic research. Euploidy ( Greek eu , "true" or "even") is the state of a cell or organism having one or more than one set of the same set of chromosomes, possibly excluding the sex-determining chromosomes . For example, most human cells have 2 of each of
2178-423: The monoploid number ( x ). The haploid number ( n ) refers to the total number of chromosomes found in a gamete (a sperm or egg cell produced by meiosis in preparation for sexual reproduction). Under normal conditions, the haploid number is exactly half the total number of chromosomes present in the organism's somatic cells, with one paternal and maternal copy in each chromosome pair. For diploid organisms,
2244-425: The salivary gland , elaiosome , endosperm , and trophoblast can exceed this, up to 1048576-ploid in the silk glands of the commercial silkworm Bombyx mori . The chromosome sets may be from the same species or from closely related species. In the latter case, these are known as allopolyploids (or amphidiploids, which are allopolyploids that behave as if they were normal diploids). Allopolyploids are formed from
2310-453: The 23 homologous monoploid chromosomes, for a total of 46 chromosomes. A human cell with one extra set of the 23 normal chromosomes (functionally triploid) would be considered euploid. Euploid karyotypes would consequentially be a multiple of the haploid number , which in humans is 23. Aneuploidy is the state where one or more individual chromosomes of a normal set are absent or present in more than their usual number of copies (excluding
2376-407: The 23 homologous pairs of chromosomes that humans normally have. This results in two homologous pairs within each of the 23 homologous pairs, providing a full complement of 46 chromosomes. This total number of individual chromosomes (counting all complete sets) is called the chromosome number or chromosome complement . The number of chromosomes found in a single complete set of chromosomes is called
2442-572: The absence or presence of complete sets, which is considered euploidy). Unlike euploidy, aneuploid karyotypes will not be a multiple of the haploid number. In humans, examples of aneuploidy include having a single extra chromosome (as in Down syndrome , where affected individuals have three copies of chromosome 21) or missing a chromosome (as in Turner syndrome , where affected individuals have only one sex chromosome). Aneuploid karyotypes are given names with
2508-438: The basal ones, while the upper ones are bract like. The hermaphrodite (bisexual) flowers are terminal to stem and branches. They are usually pentamerous (with five spreading perianth petaloid sepal segments). Five tubular honey-leaves are semi erect with a flat limb and spurred or saccate at the base. The spur is directed backwards and secretes nectar . Stamens are numerous (often more than 50) in whorls of 5,
2574-437: The chromosome constitution. Dihaploids (which are diploid) are important for selective breeding of tetraploid crop plants (notably potatoes), because selection is faster with diploids than with tetraploids. Tetraploids can be reconstituted from the diploids, for example by somatic fusion. The term "dihaploid" was coined by Bender to combine in one word the number of genome copies (diploid) and their origin (haploid). The term
2640-453: The chromosome number is generally reduced only by the specialized process of meiosis, the somatic cells of the body inherit and maintain the chromosome number of the zygote by mitosis. However, in many situations somatic cells double their copy number by means of endoreduplication as an aspect of cellular differentiation . For example, the hearts of two-year-old human children contain 85% diploid and 15% tetraploid nuclei, but by 12 years of age
2706-725: The collection started to succumb to Aquilegia Downy Mildew Peronospora aquilegiicola which was at the time an emerging disease to which the plants had no resistance. By 2018 the entire collection had been lost. Aquilegia can be grown from seeds or rhizomes. The flowers of various species of columbine were consumed in moderation by Native Americans as a condiment with other fresh greens, and are reported to be very sweet, and safe if consumed in small quantities. The plant's seeds and roots, however, are highly poisonous and contain cardiogenic toxins which cause both severe gastroenteritis and heart palpitations if consumed as food. Native Americans used very small amounts of Aquilegia root as
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2772-499: The condition is called triploid syndrome . In unicellular organisms the ploidy nutrient limitation hypothesis suggests that nutrient limitation should encourage haploidy in preference to higher ploidies. This hypothesis is due to the higher surface-to-volume ratio of haploids, which eases nutrient uptake, thereby increasing the internal nutrient-to-demand ratio. Mable 2001 finds Saccharomyces cerevisiae to be somewhat inconsistent with this hypothesis however, as haploid growth
2838-423: The diploid stage are under less efficient natural selection than those genes expressed in the haploid stage is referred to as the “masking theory”. Evidence in support of this masking theory has been reported in studies of the single-celled yeast Saccharomyces cerevisiae . In further support of the masking theory, evidence of strong purifying selection in haploid tissue-specific genes has been reported for
2904-466: The flowers. Columbine is a hardy perennial , which propagates by seed. It will grow to a height of 40–50 cm (15–20 in). It will grow in full sun; however, it prefers growing in partial shade and well drained soil, and is able to tolerate average soils and dry soil conditions. Columbine is rated at hardiness zone 3 in the United States so does not require mulching or protection in
2970-425: The gametes produced by the tetraploid organism in the example above, since these gametes are numerically diploid. The term monoploid is often used as a less ambiguous way to describe a single set of chromosomes; by this second definition, haploid and monoploid are identical and can be used interchangeably. Gametes ( sperm and ova ) are haploid cells. The haploid gametes produced by most organisms combine to form
3036-419: The haploid number n = 21). The gametes are haploid for their own species, but triploid, with three sets of chromosomes, by comparison to a probable evolutionary ancestor, einkorn wheat . Tetraploidy (four sets of chromosomes, 2 n = 4 x ) is common in many plant species, and also occurs in amphibians , reptiles , and insects . For example, species of Xenopus (African toads) form
3102-532: The hybridization of two separate species. In plants, this probably most often occurs from the pairing of meiotically unreduced gametes , and not by diploid–diploid hybridization followed by chromosome doubling. The so-called Brassica triangle is an example of allopolyploidy, where three different parent species have hybridized in all possible pair combinations to produce three new species. Polyploidy occurs commonly in plants, but rarely in animals. Even in diploid organisms, many somatic cells are polyploid due to
3168-583: The idea that haploidy is selected by harsher conditions – is cast into doubt by these results. Older WGDs have also been investigated. Only as recently as 2015 was the ancient whole genome duplication in Baker's yeast proven to be allopolyploid , by Marcet-Houben and Gabaldón 2015. It still remains to be explained why there are not more polyploid events in fungi, and the place of neopolyploidy and mesopolyploidy in fungal history . The concept that those genes of an organism that are expressed exclusively in
3234-430: The innermost being scarious staminodes . There are ten membranaceous intrastaminal scales. There are five pistils and the carpels are free. The fruit has several (five to 15) follicles which are semi erect and slightly connate downwards. These hold many seeds and are formed at the end of the pistils. The nectar is mainly consumed by long-beaked birds such as hummingbirds. Almost all Aquilegia species have
3300-455: The monoploid number and haploid number are equal; in humans, both are equal to 23. When a human germ cell undergoes meiosis, the diploid 46 chromosome complement is split in half to form haploid gametes. After fusion of a male and a female gamete (each containing 1 set of 23 chromosomes) during fertilization , the resulting zygote again has the full complement of 46 chromosomes: 2 sets of 23 chromosomes. Euploidy and aneuploidy describe having
3366-418: The most generic sense, haploid refers to having the number of sets of chromosomes normally found in a gamete . Because two gametes necessarily combine during sexual reproduction to form a single zygote from which somatic cells are generated, healthy gametes always possess exactly half the number of sets of chromosomes found in the somatic cells, and therefore "haploid" in this sense refers to having exactly half
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#17327811741023432-565: The number of chromosomes may have originated in this way, this is no longer clear, and the monoploid number is regarded as the same as the haploid number. Thus in humans, x = n = 23. Diploid cells have two homologous copies of each chromosome , usually one from the mother and one from the father . All or nearly all mammals are diploid organisms. The suspected tetraploid (possessing four-chromosome sets) plains viscacha rat ( Tympanoctomys barrerae ) and golden viscacha rat ( Pipanacoctomys aureus ) have been regarded as
3498-406: The number of sets of chromosomes found in a somatic cell. By this definition, an organism whose gametic cells contain a single copy of each chromosome (one set of chromosomes) may be considered haploid while the somatic cells, containing two copies of each chromosome (two sets of chromosomes), are diploid. This scheme of diploid somatic cells and haploid gametes is widely used in the animal kingdom and
3564-694: The only known exceptions (as of 2004). However, some genetic studies have rejected any polyploidism in mammals as unlikely, and suggest that amplification and dispersion of repetitive sequences best explain the large genome size of these two rodents. All normal diploid individuals have some small fraction of cells that display polyploidy . Human diploid cells have 46 chromosomes (the somatic number, 2n ) and human haploid gametes (egg and sperm) have 23 chromosomes ( n ). Retroviruses that contain two copies of their RNA genome in each viral particle are also said to be diploid. Examples include human foamy virus , human T-lymphotropic virus , and HIV . Polyploidy
3630-409: The organism as it now reproduces. Common wheat ( Triticum aestivum ) is an organism in which x and n differ. Each plant has a total of six sets of chromosomes (with two sets likely having been obtained from each of three different diploid species that are its distant ancestors). The somatic cells are hexaploid, 2 n = 6 x = 42 (where the monoploid number x = 7 and
3696-403: The plant Scots Pine . The common potato ( Solanum tuberosum ) is an example of a tetraploid organism, carrying four sets of chromosomes. During sexual reproduction, each potato plant inherits two sets of 12 chromosomes from the pollen parent, and two sets of 12 chromosomes from the ovule parent. The four sets combined provide a full complement of 48 chromosomes. The haploid number (half of 48)
3762-400: The proportions become approximately equal, and adults examined contained 27% diploid, 71% tetraploid and 2% octaploid nuclei. There is continued study and debate regarding the fitness advantages or disadvantages conferred by different ploidy levels. A study comparing the karyotypes of endangered or invasive plants with those of their relatives found that being polyploid as opposed to diploid
3828-684: The rest of the body being diploid (as in the mammalian liver ). For many organisms, especially plants and fungi, changes in ploidy level between generations are major drivers of speciation . In mammals and birds, ploidy changes are typically fatal. There is, however, evidence of polyploidy in organisms now considered to be diploid, suggesting that polyploidy has contributed to evolutionary diversification in plants and animals through successive rounds of polyploidization and rediploidization. Humans are diploid organisms, normally carrying two complete sets of chromosomes in their somatic cells: one copy of paternal and maternal chromosomes, respectively, in each of
3894-581: The same given name . If an internal link led you here, you may wish to change that link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Udval&oldid=1005611697 " Categories : Given names Feminine given names Hidden categories: Articles with short description Short description with empty Wikidata description All set index articles Aquilegia 130, see text Aquilina Bubani, nom. illeg. Aquilegia (common names: granny's bonnet , columbine )
3960-450: The same organism . Though polyploidy in humans is not viable, mixoploidy has been found in live adults and children. There are two types: diploid-triploid mixoploidy, in which some cells have 46 chromosomes and some have 69, and diploid-tetraploid mixoploidy, in which some cells have 46 and some have 92 chromosomes. It is a major topic of cytology. Dihaploid and polyhaploid cells are formed by haploidisation of polyploids, i.e., by halving
4026-462: The same organism, and at different stages in an organism's life cycle. Half of all known plant genera contain polyploid species, and about two-thirds of all grasses are polyploid. Many animals are uniformly diploid, though polyploidy is common in invertebrates, reptiles, and amphibians. In some species, ploidy varies between individuals of the same species (as in the social insects ), and in others entire tissues and organ systems may be polyploid despite
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#17327811741024092-500: The same species or at different stages of the life cycle . In some insects it differs by caste . In humans, only the gametes are haploid, but in many of the social insects , including ants , bees , and termites , males develop from unfertilized eggs, making them haploid for their entire lives, even as adults. In the Australian bulldog ant, Myrmecia pilosula , a haplodiploid species, haploid individuals of this species have
4158-547: The suffix -somy (rather than -ploidy , used for euploid karyotypes), such as trisomy and monosomy . Homoploid means "at the same ploidy level", i.e. having the same number of homologous chromosomes . For example, homoploid hybridization is hybridization where the offspring have the same ploidy level as the two parental species. This contrasts with a common situation in plants where chromosome doubling accompanies or occurs soon after hybridization. Similarly, homoploid speciation contrasts with polyploid speciation . Zygoidy
4224-491: The terms haploid and diploid in 1905. Some authors suggest that Strasburger based the terms on August Weismann 's conception of the id (or germ plasm ), hence haplo- id and diplo- id . The two terms were brought into the English language from German through William Henry Lang 's 1908 translation of a 1906 textbook by Strasburger and colleagues. The term haploid is used with two distinct but related definitions. In
4290-463: The visitors to A. formosa , while hawkmoths would only visit A. pubescens when given a choice. Such a " pollination syndrome ", being due to flower color and orientation controlled by their genetics , ensures reproductive isolation and can be a cause of speciation . Aquilegia petals show an enormous range of petal spur length diversity ranging from a centimeter to the 15 cm spurs of Aquilegia longissima . Selection from pollinator shifts
4356-500: The winter. Large numbers of hybrids are available for the garden, since the European A. vulgaris was hybridized with other European and North American varieties. Aquilegia species are very interfertile, and will self-sow. Some varieties are short-lived so are better treated as biennials . The British National Collection of Aquilegia s was held by Mrs Carrie Thomas at Killay near Swansea . Some time during or before 2014
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