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Polyploidy occurs in cells and organisms when there are more than two homologous sets of chromosomes. The cell is the structural and functional unit of all known living Organisms It is the smallest unit of an organism that is classified as living and is often called Homologous chromosomes are Chromosomes in a Biological cell that pair ( synapse) during Meiosis, or alternatively non-identical chromosomes that A chromosome is an organized structure of DNA and Protein that is found in cells. Polyploid types are labelled according to the number of chromosome sets in the nucleus:

A diagram that summarizes all well-known polyploidization events. See Paleopolyploidy for more detail
A diagram that summarizes all well-known polyploidization events. In Cell biology, the nucleus (pl nuclei; from Latin la ''nucleus'' or la ''nuculeus'' "little nut" or kernel is a membrane-enclosed A phylum ( Plural: phyla) is a Taxonomic rank between Kingdom and above Class. Tardigrades (commonly known as water bears) form the Phylum Tardigrada, part of the superphylum Ecdysozoa. Salmonidae is a family of Ray-finned fish, the only living family of the order Salmoniformes. Wheat ( Triticum spp is a worldwide cultivated grass from the Levant area of the Middle East. Acipenser is Genus of Sturgeons. With about 18 species many of which are Threatened, it is the largest genus in the order Acipenseriformes Sturgeon is the Common name used for some 26 species of fish in the family Acipenseridae, including the genera Acipenser, Fragaria is the name of a Genus of Plants in the family Rosaceae, commonly known as strawberries for their edible Fruits Celosia argentea, commonly known as plumed cockscomb, is a plant of tropical origin and is known for its very bright colors See Paleopolyploidy for more detail

Most organisms are normally diploid; polyploidy may occur due to abnormal cell division. Paleopolyploidy refers to ancient Genome duplications which occurred at least several million years ago (mya "Haplo" redirects here For the fictional character see The Death Gate Cycle. Cell division is a process by which a cell, called the parent cell divides into two or more cells called daughter cells. It is most commonly found in plants. Haploidy may also occur as a normal stage in an organism's life. "Haplo" redirects here For the fictional character see The Death Gate Cycle. A haploid has only one set of chromosomes.

Polyploidy occurs in some animals, such as goldfish, salmon, and salamanders, but is especially common among ferns and flowering plants, including both wild and cultivated species. The goldfish, Carassius auratus, was one of the earliest Fish to be domesticated, and is still one of the most commonly kept aquarium fish and Salmon is the common name for several species of Fish of the family Salmonidae. Salamander (orig from Persian: sām, "fire" and andarūn, "within" is the common name for a group of approximately 500 Species A fern is any one of a group of about 20000 Species of Plants classified in the phylum or division Pteridophyta, also known as Filicophyta Plants are living Organisms belonging to the kingdom Plantae. In Biology, a species is one of the basic units of Biological classification and a Taxonomic rank. Wheat, for example, after millennia of hybridization and modification by humans, has strains that are diploid (two sets of chromosomes), tetraploid (four sets of chromosomes) with the common name of durum or macaroni wheat, and hexaploid (six sets of chromosomes) with the common name of bread wheat. Wheat ( Triticum spp is a worldwide cultivated grass from the Levant area of the Middle East. In Biology, hybrid has two meanings The first meaning is the result of interbreeding between two animals or plants of different taxa. Durum wheat or macaroni wheat (also spelled Durhum Triticum durum or Triticum turgidum durum) is the only Tetraploid species of Wheat thumb|right|200px|Macaroni thumb|right|200px|Macaroni and cheese Macaroni is a kind of moderately extended machine-made dry Pasta. Many agriculturally important plants of the genus Brassica are also tetraploids; their relationship is described by the Triangle of U. Brassica ( Brás-si-ca) is a genus of plants in the mustard family ( Brassicaceae) The Triangle of U is a theory about the evolution and relationships between members of the Plant Genus Brassica.

The occurrence of polyploidy is a mechanism of speciation and is known to have resulted in new species of the plant Salsify (also known as "goatsbeard"). See also Aruncus, which is also known as "goatsbeard"

Speciation via polyploidy: A diploid cell undergoes failed meiosis, producing diploid gametes, which self-fertilize to produce a tetraploid zygote.
Speciation via polyploidy: A diploid cell undergoes failed meiosis, producing diploid gametes, which self-fertilize to produce a tetraploid zygote. "Haplo" redirects here For the fictional character see The Death Gate Cycle. In Biology or life science meiosis (pronounced my-oh-sis is a process of reductional division in which the number of chromosomes per cell is cut in half A gamete (from Ancient Greek γαμέτης; translated gamete = wife gametes = husband is a cell that fuses with another gamete For other meanings see Zygote (disambiguation. A zygote (from Greek ζυγωτός zugōtos "joined" or "yoked"

Examples in animals are more common in the ‘lower’ forms such as flatworms, leeches, and brine shrimp. The flatworms (Phylum Platyhelminthes from the Greek πλατύ platy, meaning "flat" and ἕλμινς (root ἑλμινθ- helminth- Leeches are Annelids comprising the Subclass Hirudinea. There are freshwater terrestrial and marine leeches Brine shrimp are a species of aquatic Crustaceans of the Genus Artemia. Polyploid animals are often sterile, so they often reproduce by parthenogenesis. Parthenogenesis (from the Greek παρθένος parthenos, "virgin" + γένεσις genesis, "creation" is an asexual form Polyploid salamanders and lizards are also quite common and parthenogenetic. While mammalian liver cells are polyploid, rare instances of polyploid mammals are known, but most often result in prenatal death. Mammals ( class Mammalia) are a class of Vertebrate Animals characterized by the presence of Sweat glands, including sweat glands Pregnancy ( Latin graviditas) is the carrying of one or more offspring known as a Fetus or Embryo, inside the Uterus of a Female

One of the only known exceptions to this 'rule' is an octodontid rodent of Argentina's harsh desert regions, known as the Red Viscacha-Rat (Tympanoctomys barrerae). The Octodontidae are a family Rodents restricted to south-western South America. Rodentia is an order of Mammals also known as rodents, characterised by two continuously-growing incisors in the upper and lower jaws which must For a topic outline on this subject see List of basic Argentina topics. A desert is a Landscape or region that receives very little precipitation. UserPolbot. -->The Plains Viscacha Rat or Red Vizcacha Rat ( Tympanoctomys barrerae) is a species of This rodent is not a rat, but kin to guinea pigs and chinchillas. Rats are various medium sized long-tailed Rodents of the superfamily Muroidea The Guinea pig (also commonly called the cavy after its scientific name Cavia porcellus) is a species of Rodent belonging to the family Caviidae Chinchillas are rabbit-sized Crepuscular Rodents native to the Andes mountains in South America. Its "new" diploid [2n] number is 102 and so its cells are roughly twice normal size. Its closest living relation is Octomys mimax, the Andean Viscacha-Rat of the same family, whose 2n=56. The Andes form the world's longest exposed Mountain range. They lie as a continuous chain of highland along the western coast of South America. It is surmised that an Octomys-like ancestor produced tetraploid (i. e. , 4n=112) offspring that were, by virtue of their doubled chromosomes, reproductively isolated from their parents; but that these likely survived the ordinarily catastrophic effects of polyploidy in mammals by shedding (via translocation or some similar mechanism) the "extra" set of sex chromosomes gained at this doubling. In Genetics, a chromosome translocation is a Chromosome abnormality caused by rearrangement of parts between nonhomologous Chromosomes. The XY sex-determination system is the Sex-determination system found in Humans most other Mammals some insects ( Drosophila) and some

Polyploidy can be induced in cell culture by some chemicals: the best known is colchicine, which can result in chromosome doubling, though its use may have other less obvious consequences as well. Colchicine is a highly poisonous Natural product and Secondary metabolite, originally extracted from plants of the genus Colchicum ( Autumn

There are large number of polyploid crop varieties - See Polyploid Crops below. Polyploidy occurs in cells and Organisms when there are more than two homologous sets of Chromosomes.

There are few naturally occurring polyploid conifers. One example is the giant tree Sequoia sempervirens or Coast Redwood which is a hexaploid (6x) with 66 chromosomes (2n=6x=66), although the origin is unclear [1]. A tree is a perennial Woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or Sequoia sempervirens is the sole living Species of the Genus Sequoia in the cypress family Cupressaceae (formerly Sequoia sempervirens is the sole living Species of the Genus Sequoia in the cypress family Cupressaceae (formerly

Contents

Polyploidy in humans (Aneuploidy)

True polyploidy rarely occurs in humans, although it occurs in some tissues (especially in the liver). Polyploidy refers to a numerical change in a whole set of chromosomes. Organisms in which a particular chromosome, or chromosome segment, is under- or overrepresented are said to be aneuploid (from the Greek words meaning "not," "good," and "fold"). Therefore the distinction between aneuploidy and polyploidy is that aneuploidy refers to a numerical change in part of the chromosome, whereas polyploidy refers to a numerical change in the whole set of chromosomes. [2]

Polyploidy occurs in humans in the form of triploidy (69,XXX) and tetraploidy (92,XXXX), not to be confused with 47,XXX or 48, XXXX aneuploidy. Triple X syndrome is a form of chromosomal variation characterized by the presence of an extra X chromosome in each cell of a human female Triple X syndrome is a form of chromosomal variation characterized by the presence of an extra X chromosome in each cell of a human female Triploidy, usually due to polyspermy, occurs in about 2-3% of all human pregnancies and ~15% of miscarriages. In biology polyspermy describes an egg that has been fertilized by more than one sperm. The vast majority of triploid conceptions end as miscarriage and those that do survive to term typically die shortly after birth. Miscarriage or spontaneous abortion is the natural or spontaneous end of a Pregnancy at a stage where the embryo or fetus is incapable of surviving generally defined In some cases survival past birth may occur longer if there is mixoploidy with both a diploid and a triploid cell population present. "Haplo" redirects here For the fictional character see The Death Gate Cycle. "Haplo" redirects here For the fictional character see The Death Gate Cycle.

Triploidy may be the result of either digyny (the extra haploid set is from the mother) or diandry (the extra haploid set is from the father). Diandry is almost always caused by the fertilization of an egg by two sperm (dispermy). For soil improvement see Fertilization (soil. Digyny is most commonly caused by either failure of one meiotic division during oogenesis leading to a diploid oocyte or failure to extrude one polar body from the oocyte. An oocyte, ovocyte, or rarely ocyte, is a female Gametocyte or Germ cell involved in reproduction. A polar body is a cell structure found inside an Ovum. Both Animal and Plant ova possess it An oocyte, ovocyte, or rarely ocyte, is a female Gametocyte or Germ cell involved in reproduction. Diandry appears to predominate among early miscarriages while digyny predominates among triploidy that survives into the fetal period. Miscarriage or spontaneous abortion is the natural or spontaneous end of a Pregnancy at a stage where the embryo or fetus is incapable of surviving generally defined However, among early miscarriages, digyny is also more common in those cases <8. 5 weeks gestational age or those in which an embryo is present. There are also two distinct phenotypes in triploid placentas and fetuses that are dependent on the origin of the extra haploid set. A phenotype is any observable characteristic of an Organism, such as its morphology, Development, biochemical or physiological properties The placenta is an Ephemeral organ present in placental Vertebrates, such as Eutherial Mammals and Sharks during Gestation A fetus (or foetus or fœtus) is a developing Mammal or other Viviparous Vertebrate, after the Embryonic stage and "Haplo" redirects here For the fictional character see The Death Gate Cycle. In digyny there is typically an asymmetric poorly grown fetus, with marked adrenal hypoplasia and a very small placenta. A fetus (or foetus or fœtus) is a developing Mammal or other Viviparous Vertebrate, after the Embryonic stage and In Mammals the adrenal glands (also known as suprarenal glands) are the triangle-shaped Endocrine glands that sit on top of the Kidneys their Hypoplasia is underdevelopment or incomplete development of a tissue or organ The placenta is an Ephemeral organ present in placental Vertebrates, such as Eutherial Mammals and Sharks during Gestation In diandry, the fetus (when present) is typically normally grown or symmetrically growth restricted, with normal adrenal glands and an abnormally large cystic placenta that is called a partial hydatidiform mole. In Mammals the adrenal glands (also known as suprarenal glands) are the triangle-shaped Endocrine glands that sit on top of the Kidneys their Molar pregnancy is an abnormal form of Pregnancy, characterized by the presence of a hydatidiform mole (or hydatid mole, mola hytadidosa These parent-of-origin effects reflect the effects of genomic imprinting. Genomic imprinting is a genetic phenomenon by which certain Genes are expressed in a Parent -of-origin-specific manner

Complete tetraploidy is more rarely diagnosed than triploidy, but is observed in 1-2% of early miscarriages. However, some tetraploid cells are not uncommonly found in chromosome analysis at prenatal diagnosis and these are generally considered ‘harmless’. Prenatal testing is Testing for diseases or conditions in a Fetus or Embryo before it is born It is not clear whether these tetraploid cells simply tend to arise during in vitro cell culture or whether they are also present in placental cells in vivo. There are, at any rate, very few clinical reports of fetuses/infants diagnosed with tetraploidy mosaicism.

Mixoploidy is quite commonly observed in human preimplantation embryos and includes haploid/diploid as well as diploid/tetraploid mixed cell populations. "Haplo" redirects here For the fictional character see The Death Gate Cycle. It is unknown whether these embryos fail to implant and are therefore rarely detected in ongoing pregnancies or if there is simply a selective process favoring the diploid cells.

Polyploidy in plants

Polyploidy is pervasive in plants and some estimates suggest that 30-80% of living plant species are polyploid, and many lineages show evidence of ancient polyploidy (paleopolyploidy) in their genomes. [3] Huge explosions in angiosperm species diversity appear to have coincided with the timing of ancient genome duplications shared by many species. The flowering plants or angiosperms ( Angiospermae or Magnoliophyta) are the most widespread group [4] Polyploid plants can arise spontaneously in nature by several mechanisms, including meiotic or mitotic failures, and fusion of unreduced (2n) gametes. [5] Both autopolyploids (eg. potato) and allopolyploids (eg. canola, wheat, cotton) can be found among both wild and domesticated plant species. Most polyploids display heterosis relative to their parental species, and may display novel variation or morphologies that may contribute to the processes of speciation and eco-niche exploitation. Heterosis is a term used in Genetics and Selective breeding. The term heterosis also known as hybrid vigor or outbreeding enhancement, Speciation is the Evolutionary process by which new biological Species arise [6] The mechanisms leading to novel variation in newly formed allopolyploids may include gene dosage effects (resulting from more numerous copies of genome content), the reunion of divergent gene regulatory hierarchies, chromosomal rearrangements, and epigenetic remodeling, all of which affect gene content and/or expression levels. In Biology, the term epigenetics refers to changes in Gene expression caused by mechanisms other than changes in the underlying DNA sequence [7] Many of these rapid changes may contribute to reproductive isolation and speciation.

Polyploid crops

Polyploid plants tend to be larger and better at flourishing in early succession habitats such as farm fields. In the breeding of crops, the tallest and best thriving plants are selected for. Thus, many crops (and agricultural weeds) may have unintentionally been bred to a higher level of ploidy. WEED (1390 AM) is a Radio station broadcasting a Spanish format

The induction of polyploidy is a common technique to overcome the sterility of a hybrid species during plant breeding. For example, Triticale is the hybrid of wheat (Triticum turgidum) and rye (Secale cereale). Triticale (× Triticosecale) is a hybrid of Wheat ( Triti cum) and Rye ( Se' cale) first bred Rye ( Secale cereale) is a grass grown extensively as a grain and forage crop It combines sought-after characteristics of the parents, but the initial hybrids are sterile. After polyploidization, the hybrid becomes fertile and can thus be further propagated to become triticale.

In some situations polyploid crops are preferred because they are sterile. For example many seedless fruit varieties are seedless as a result of polyploidy. Such crops are propagated using asexual techniques such as grafting.

Polyploidy in crop plants is most commonly induced by treating seeds with the chemical colchicine. Colchicine is a highly poisonous Natural product and Secondary metabolite, originally extracted from plants of the genus Colchicum ( Autumn

Examples of Polyploid Crops

Some crops are found in a variety of ploidy. For the fruit see Banana. For other meanings see Banana (disambiguation. The apple is the pomaceous Fruit of the apple tree Species Malus domestica in the Rose family Rosaceae. Ginger is commonly used as a cooking spice throughout the world Watermelon ( Citrullus lanatus ( Thunb) Matsum & Nakai family Cucurbitaceae) refers to both Fruit and Plant of a vine-like (climber Citrus is a common term and Genus of Flowering plants in the family Rutaceae, originating in tropical and subtropical southeast regions of Durum wheat or macaroni wheat (also spelled Durhum Triticum durum or Triticum turgidum durum) is the only Tetraploid species of Wheat thumb|right|200px|Macaroni thumb|right|200px|Macaroni and cheese Macaroni is a kind of moderately extended machine-made dry Pasta. Wheat ( Triticum spp is a worldwide cultivated grass from the Levant area of the Middle East. Maize (ˈmeɪz ( Zea mays L. ssp mays) known as corn in some countries is a cereal grain domesticated in Mesoamerica Cotton is a soft staple Fibre that grows around the seeds of the cotton plant ( Gossypium sp The potato is a Starchy Tuberous crop Vegetable from the perennial Solanum tuberosum of the Solanaceae The cabbage ( Brassica oleracea var capitata) is a leafy garden plant of the Family Brassicaceae (or Cruciferae used as a The leek, Allium ampeloprasum var porrum (L also sometimes known as Allium porrum, is a vegetable which belongs along with the Onion and Tobacco is an Agricultural product recognized as an addictive drug processed from the fresh Leaves of plants in the genus Nicotiana. The peanut, or Groundnut ( Arachis hypogaea) is a species in the Legume family Fabaceae native to South America, Mexico Kinnow (also Kinoo) is a Citrus fruit variety grown in Pakistan and to a lesser extent in north Indian states mainly Punjab Pelargonium is a Genus of Flowering plants which includes about 200 Species of perennial, succulent, and Shrub Chrysanthemums, often called 'mums' are a genus ( Chrysanthemum) of about 30 species of perennial Flowering plants in the family Asteraceae Wheat ( Triticum spp is a worldwide cultivated grass from the Levant area of the Middle East. Triticale (× Triticosecale) is a hybrid of Wheat ( Triti cum) and Rye ( Se' cale) first bred Oats redirects here It may mean either the common cereal oat discussed here or any cultivated or wild species of the Genus Avena. Garden strawberries are a common variety of strawberry cultivated worldwide Dahlia is a Genus of bushy tuberous, Perennial plants native to Mexico, Central America, and Colombia. The pansy or pansy violet s are a large group of plants cultivated as garden Flowers Pansies are derived from Viola tricolor and can include Sugarcane ( Saccharum) is a genus of 6 to 37 species (depending on taxonomic interpretation of tall perennial grasses (family Poaceae tribe Andropogoneae Apples, tulips and lilies are commonly found as both diploid and as triploid. Tulipa, commonly called tulip, is a Genus of about 150 species of bulbous Flowering plants in the family Liliaceae. Daylilies (Hemerocallis) cultivars are available as either diploid or tetraploid. Daylilies comprise the small Genus Hemerocallis of flowering plants in the family Hemerocallidaceae. Kinnows can be tetraploid, diploid, or triploid. Kinnow (also Kinoo) is a Citrus fruit variety grown in Pakistan and to a lesser extent in north Indian states mainly Punjab

Terminology

Autopolyploidy

Autopolyploids are polyploids with multiple chromosome sets derived from a single species. Autopolyploids can arise from a spontaneous, naturally occurring genome doubling (for example, the potato). In classical genetics the genome of a Diploid Organism including Eukarya refers to a full set of chromosomes or genes in a Gamete, thereby Others might form following fusion of 2n gametes (unreduced gametes). A gamete (from Ancient Greek γαμέτης; translated gamete = wife gametes = husband is a cell that fuses with another gamete Bananas and apples can be found as triploid autopolyploids. Autopolyploid plants typically display polysomic inheritance, and are therefore often infertile and propagated clonally

Allopolyploidy

Allopolyploids are polyploids with chromosomes derived from different species. Triticale is an example of an allopolyploid, having six chromosome sets, four from wheat (Triticum turgidum) and two from rye (Secale cereale). Triticale (× Triticosecale) is a hybrid of Wheat ( Triti cum) and Rye ( Se' cale) first bred Amphidiploid is another word for an allopolyploid. Some of the best examples of allopolyploids come from the Brassicas, and the Triangle of U describes the relationships among the three common diploid Brassicas (B. Brassica ( Brás-si-ca) is a genus of plants in the mustard family ( Brassicaceae) oleracea, B. rapa, and B. nigra) and three allotetraploids (B. napus, B. juncea, and B. carinata) derived from hybridization among the diploids.

Homoeologous

The term is used to describe the relationship of similar chromosomes or parts of chromosomes brought together following inter-species hybridization and allopolyploidization, and whose relationship was completely homologous in an ancestral species. In allopolyploids, the homologous chromosomes within each parental sub-genome should pair faithfully during meiosis, leading to disomic inheritance; however in some allopolyploids, the homoeologous chromosomes of the parental genomes may be nearly as similar to one another as the homologous chromosomes, leading to tetrasomic inheritance (four chromosomes pairing at meiosis), intergenomic recombination, and reduced fertility. In Biology or life science meiosis (pronounced my-oh-sis is a process of reductional division in which the number of chromosomes per cell is cut in half

Homologous

The term is used to describe the relationship of similar chromosomes that pair at mitosis and meiosis. Mitosis is the process in which a Eukaryotic cell separates the Chromosomes in its Cell nucleus, into two identical sets in two daughter nuclei In Biology or life science meiosis (pronounced my-oh-sis is a process of reductional division in which the number of chromosomes per cell is cut in half In a diploid, one homolog is derived from the male parent (pollen or sperm) and one is derived from the female parent (egg). During meiosis and gametogenesis, homologous chromosomes pair and exchange genetic material by recombination, leading to the production of sperm/pollen or eggs with chromosome haplotypes containing novel genetic variation. Gametogenesis is a process by which diploid or haploid precursor cells undergo cell division and differentiation to form mature haploid Gametes Depending on the Biological The term haplotype is a contraction of the term " haploid Genotype.

Karyotype

A karyotype is the characteristic chromosome complement of a eukaryote species. A karyotype is the characteristic Chromosome complement of a Eukaryote Species. A chromosome is an organized structure of DNA and Protein that is found in cells. Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex In Biology, a species is one of the basic units of Biological classification and a Taxonomic rank. [9][10] The preparation and study of karyotypes is part of cytology and, more specifically, cytogenetics. Cytogenetics is a branch of Genetics that is concerned with the study of chromosomes and cell division

Although the replication and transcription of DNA is highly standardized in eukaryotes, the same cannot be said for their karotypes, which are highly variable between species in chromosome number and in detailed organization despite being constructed out of the same macromolecules. Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex In some cases there is even significant variation within species. This variation provides the basis for a range of studies in what might be called evolutionary cytology.

Paralogous

The term is used to describe the relationship among duplicated genes or portions of chromosomes that derived from a common ancestral DNA. Paralogous segments of DNA may arise spontaneously by errors during DNA replication, copy and paste transposons, or whole genome duplications. DNA replication is the process of copying a double-stranded DNA molecule to form two double-stranded molecules Transposons are sequences of DNA that can move around to different positions within the Genome of a single cell, a process called transposition

Paleopolyploidy

Main article: Paleopolyploidy

Ancient genome duplications probably occurred in the evolutionary history of all life. Paleopolyploidy refers to ancient Genome duplications which occurred at least several million years ago (mya Duplication events that occurred long ago in the history of various evolutionary lineages can be difficult to detect because of subsequent diploidization (such that a polyploid starts to behave cytogenetically as a diploid over time) as mutations and gene translations gradually make one copy of each chromosome unlike its other copy. An evolutionary lineage is a sequence of Species, that form a line of descent each new species the direct result of speciation from an immediate ancestral species

In many cases, these events can be inferred only through comparing sequenced genomes. The term DNA sequencing encompasses biochemical methods for determining the order of the Nucleotide bases Adenine, Guanine, Cytosine Examples of unexpected but recently confirmed ancient genome duplications include the baker's yeast (Saccharomyces cerevisiae), mustard weed/thale cress (Arabidopsis thaliana), rice (Oryza sativa), and an early evolutionary ancestor of the vertebrates (which includes the human lineage) and another near the origin of the teleost fishes. Yeasts are a growth form of eukaryotic Microorganisms classified in the kingdom Fungi, with about 1500 Species currently described Saccharomyces cerevisiae is a Species of Budding Yeast. It is perhaps the most useful Yeast owing to its use since ancient times Arabidopsis thaliana ( A-ra-bi-dóp-sis tha-li-á-na; thale cress, mouse-ear cress or Arabidopsis) is a small Rice is a Cereal foodstuff which forms an important part of the diet of many people worldwide and as such it is a staple food for many Rice is a Cereal foodstuff which forms an important part of the diet of many people worldwide and as such it is a staple food for many eVolution is the third Album by eLDee, it was due to be released in 2008 An ancestor is a Parent or ( recursively) the parent of an ancestor (i Vertebrates are members of the Subphylum Vertebrata, Chordates with backbones or spinal columns The grouping sometimes includes Human beings, humans or man (Origin 1590–1600 L homō man OL hemō the earthly one (see Humus Teleostei is one of three infraclasses in class Actinopterygii, the ray-finned fishes Fish are aquatic Vertebrate animals that are typically ectothermic (previously Cold-blooded) covered with scales, and equipped with two Angiosperms (flowering plants) have paleopolyploidy in their ancestry. The flowering plants or angiosperms ( Angiospermae or Magnoliophyta) are the most widespread group The flowering plants or angiosperms ( Angiospermae or Magnoliophyta) are the most widespread group All eukaryotes probably have experienced a polyploidy event at some point in their evolutionary history. Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex

See also

References

  1. ^ Ahuja MR, Neale DB. A chromosome is an organized structure of DNA and Protein that is found in cells. A karyotype is the characteristic Chromosome complement of a Eukaryote Species. In Biology or life science meiosis (pronounced my-oh-sis is a process of reductional division in which the number of chromosomes per cell is cut in half Paleopolyploidy refers to ancient Genome duplications which occurred at least several million years ago (mya A polyploid complex is a group of interrelated and interbreeding plants that also have differing levels of Ploidy that can allow genetic exchanges between unrelated species Speciation is the Evolutionary process by which new biological Species arise "Origins of Polyploidy in Coast Redwood (Sequoia sempervirens (D. DON) ENDL. ) and Relationship of Coast Redwood to other Genera of Taxodiaceae" Silvae Genetica 51, 2–3 (2002)
  2. ^ Griffiths, A. J. et al. 2000. An introduction to genetic analysis, 7th ed. W. H. Freeman, New York ISBN 0-7167-3520-2
  3. ^ Meyers and Levin 2006; Rieseberg and Willis 2007; Otto 2007
  4. ^ de Bodt et al 2005
  5. ^ Comai 2005
  6. ^ Comai 2005; Rieseberg and Willis 2007
  7. ^ Osborn et al. , 2003; Chen and Ni 2006; Chen 2007
  8. ^ Seedless Fruits Make Others Needless
  9. ^ White M. J. D. 1973. The chromosomes. 6th ed, Chapman & Hall, London. p28
  10. ^ Stebbins G. L. 1950. Variation and evolution in plants. Chapter XII: The Karyotype. Columbia University Press N. Y.

Further reading

External links

Dictionary

polyploidy

-noun

  1. (genetics) the state or condition of being a polyploid; having more than the usual number of complete sets of chromosomes
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