Search results
Results From The WOW.Com Content Network
Speciation via polyploidy: A diploid cell undergoes failed meiosis, producing diploid gametes, which self-fertilize to produce a tetraploid zygote. Polyploidy is frequent in plants, some estimates suggesting that 30–80% of living plant species are polyploid, and many lineages show evidence of ancient polyploidy (paleopolyploidy) in their genomes.
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. [citation needed] It is possible for polyploid organisms to revert to lower ploidy by haploidisation. [citation needed]
Once a polyploid is made, either synthetically or naturally, the genome goes through a period of "genome shock". Genome shock can be defined as a stage in which the genome experiences massive reorganization and structural changes to deal with the external stress (X-ray damage, chromosome duplication, etc.) imposed upon the genome. [ 7 ]
A diagram that summarizes all well-known paleopolyploidization events. Ancient genome duplications are widespread throughout eukaryotic lineages, particularly in plants. . Studies suggest that the common ancestor of Poaceae, the grass family which includes important crop species such as maize, rice, wheat, and sugar cane, shared a whole genome duplication about
A polyploid complex, also called a diploid-polyploid complex, is a group of interrelated and interbreeding species that also have differing levels of ploidy that can allow interbreeding. A polyploid complex was described by E. B. Babcock and G. Ledyard Stebbins in their 1938 monograph The American Species of Crepis : their interrelationships ...
The Vietnamese Wikipedia initially went online in November 2002, with a front page and an article about the Internet Society.The project received little attention and did not begin to receive significant contributions until it was "restarted" in October 2003 [3] and the newer, Unicode-capable MediaWiki software was installed soon after.
Sóc Trăng (362,029 people, constituting 30.18% of the province's population and 27.43% of all Khmer in Vietnam), Trà Vinh (318,231 people, constituting 31.53% of the province's population and 24.11% of all Khmer in Vietnam), Kiên Giang (211,282 people, constituting 12.26% of the province's population and 16.01% of all Khmer in Vietnam), An ...
Vietnamese (tiếng Việt) is an Austroasiatic language spoken primarily in Vietnam where it is the official language. It belongs to the Vietic subgroup of the Austroasiatic language family. [5] Vietnamese is spoken natively by around 85 million people, [1] several times as many as the rest of the Austroasiatic family combined. [6]