Polyploids and Polyploidy
نویسندگان
چکیده
منابع مشابه
Polyploidy
Polyploidy is defined as an increase in genome DNA content. Throughout the plant and animal kingdoms specific cell types become polyploid as part of their differentiation programs. When this occurs in subsets of tissues within an organism it is termed somatic polyploidy, because it is distinct from the increase in ploidy that is inherited through the germline and present in every cell type of t...
متن کاملEVOLUTION OF POLYPLOIDS Reference: Harlan and deWet (1975) Origins of Polyploids Literatures relating to evolution of polyploids
Class I: Chromosome increase occurs in the first generation through the union of gametes one or both of which are unreduced. Can occur following selfor crosspollination. Class II: Chromosome doubling occurs in offspring of a hybrid with meiotic disturbances leading to unreduced gametes. It’s a second generation phenomenon: F2, BC1 or F1 crossed to a third parent. Class III: Chromosomal doubling...
متن کاملPolyploids, genome halving and phylogeny
MOTIVATION Autopolyploidization and allopolyploidization events multiply the number of chromosomes and genomic content. Genome rearrangement phylogenetics requires that all genomes analyzed have the same set of orthologs, so that it is not possible to include diploid and polyploid genomes in the same phylogeny. RESULTS We propose a framework for solving this difficulty by integrating the rear...
متن کاملPolyploidy and Cancer
The average desoxypentosenucleic acid content of individual nuclei was determined for various normal and tumor tissues, and for livers showing precancerous changes, in the rat. With certain exceptions attributable to polyploidy, the values were practically indistinguishable from each other and from values reported for cell nuclei of other mammals. The amount of this nucleic acid in diploid cell...
متن کاملPolyploidy and gender dimorphism.
Miller and Venable (1) claimed that polyploidy is a “trigger of unrecognized importance” for the evolution of gender dimorphism, an idea originally proposed by Jennings (2) and Baker (3). In our opinion, their phylogenetic analysis of North American Lycium (Solanaceae) does not support the claimed associations between polyploidy, self-fertility, and gender dimorphism. There is no support (boots...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Nature
سال: 1929
ISSN: 0028-0836,1476-4687
DOI: 10.1038/124062a0