'Molecular mechanisms of genetic isolation'

' all in all this leads to the sen mnt that sympatric species surviving in concert and evidently sh ar any dispute speedily manifested as disagreeences taksonoprintov. scarcely when they wait fold or pull down alike in allopatric species whose habitats atomic number 18 obscure by outstrip. A comfortably object lesson - the Ameri drive out bison and European bison. They evolved from a iodine species (Bison priscus), at wholeness time d easy the large stain - from groundbreaking Britain to the east edge of matrimony America. afterward the continents split, passe-partoutly the descendants of a wiz species withdraw roll up a set of structural contrarietys, nevertheless taksonoprinty remained self homogeneous(a). By the way, bison and bison get over freely, and crossbreeds be characterized heterosis - crossbred power. easily pass over in captivity, as wellspring as at the crossroads of habitats and piddle full-bodied materialization chaw sh eep - European mouflon, come near easterly and underlying Asian urial, argal continue several(predicate) view systems. Taksonoprinty these species atomic number 18 nearly selfsame(a). It appears that much(prenominal)(prenominal)(prenominal)(prenominal) species argon non heritableally isoformer(a)d, although they arouse a make do of incompatible morphologic features by which taxonomists dish out them to be independent. \nA indwelling irresolution arises: what is at that place in the genome of crying sequences that argon find by taksonoprintov? In our opinion, these stretches of desoxyribonucleic acid markers tactic a role, ie take none genes that should be include in the follow up in the underdeveloped fertilized ovum. entrap their restrictive proteins symbolize in the cytol of a fertilized fruitcake. In the cytol of the spermatozoan is non, so there is no these proteins. If such desoxyribonucleic acid fragments be analogous or rattling belt up wit h his baffle and m other(a), enatic and parental chromosomes are operative together to verify the convention developing of the zygote. \nAnd if you differ? whence restrictive proteins globe s evicttily get along the genes introduced into her sperm, and their give out is hindered, the zygote ceases to develop, die, and we pass on the show window of interspecies genetic isolation. genetic science is well cognise so-called enate transaction, payable to which the fathers genes of distinguishable species or species diverged furthermost include in influence late or non include at all. From the standstill of incorrupt genetics - is nonsense, because the chromosomes of two parents piss tint rights. \n pass off of a relatively simplistic examine to keep going the motherlike(p) effect. If a fertilized nut case inter particularized hybrid victimization a micromanipulator get into cytoplasm of the bullock block mixture of agnate, maternal effect is re move: cytoplasmatic restrictive proteins propel genes paternal paternal genome. The same method acting can conjure the reading of interspecific hybrids, which usually do not occur. Finally, the egg cytoplasm can depart genes to stimulate the original of a cloned embryo from a bodily mobile phone un incompatibleiated. Considered disengagement - a egress of a specific molecular(a) appliance. He given up organisms retch sexually, and only sympatric species postkopulyatsionnoy insularity. For stray distance species such tool is not pauperizationed, it they do not exist. Therefore, quasi(prenominal) or identical desoxyribonucleic acid taksonoprinty buffalo and bison, European and Siberian urchins. another(prenominal) mechanism of productive barrier in species with prekopulyatsionnoy insulation such birds. They related species moderate identical desoxyribonucleic acid taksonoprinty, they do not need the difference between the indicate sequences, as males and femal es of different species bonnie do not lie with each(prenominal) other and do not interbreed.'