Chii maviri-chemasanganiswa Crossover

Mitemo nhaka Mendel kuti monohybrid muchinjikwa akachengetedzwa panyaya zvikuru kunzwisisa maviri-remasanganiswa. In kwakadai nekuita mubereki siyana anosiyana zviviri zviviri zvakasiyana unhu.

Funga nezvomuenzaniso Mendel dihybrid muchinjikwa nokusimbisa mitemo. Vayambuka nemarudzi maviri pizi: nemaruva chena uye zvisingatomboiti pomukombero uye maruva nezvishava uye elongated pomukombero. All vanhu vomuzana chizvarwa akanga Maruva chakaipa chena ine whisk. Kubva ichi tichiti chena ruvara (runotaurwa C) uye inowanzotorwa urefu (nyora E) - iri rave inobudisa yepepuru ruvara (s) uye elongate whisk (e) - recessive. Kana vaizviona pollination yedzinza rokutanga miti iri rwakakamukana. Nokuda Kujeka vanoumba kuyambuka zano.

muchinjikwa First: p1 X CCEE CCEE

G 2Ss uye 2Ee

F1 CCEE

The kuberekesana wechipiri (selfing F1 VaNefirimu) p2 X CCEE CCEE. muchinjikwa Dihybrid anoenda aumbe 16 marudzi zygotes. Mumwe gamete ichange iine mumiririri mumwe kubva Gene maviri pamwe P-uye E-E yezvinoita. Kana ichi Gene C zvakaenzana mukana kunogona pamwe E kana E akavapindurawo, uye unogona nokubatanidza pamwe E kana E kunoguma chemasanganiswa CCEE siyana zvakaenzana kakawanda gamete nezvemarudzi 4: .. CE, Ge, Ce, nduro. Obedin pamwe chete, vanoumba zvinenge zvakadai: 9 kwomuzvarirwo chena Corolla, pamwe 3 chena elongate whisk 3 ane kwomuzvarirwo pomukombero magenta uye magenta 1 ane elongated pomukombero.

Muchizvarwa wechipiri kuyambuka VaNefirimu voga, kunze yakafanana nevabereki siyana, zvitarisiko vari aumba mutsva mubatanidzwa mabhii (combinative kana magene variability). Fani iyi inoita basa rinokosha mune Kushanduka goho anofambidzana itsva adaptive zvinoyemurika. Uyewo vachishingaira kushandiswa maberekero, apo crossbreeding zvinomera uye mhuka akavandudzika mhando uye dzinoita zvinoita kuti kusuma dzinowanika.

Kuwanda phenotypes muna F2 idukusa nokuwanda genotypes. Izvi imhaka yokuti mubatanidzwa gametes akasiyana kunogona kupa zvakafanana morphological unhu. Saka, isu tiwane kukamurwa phenotype - 9: 3: 3: 1.

Izvi zviviri-chemasanganiswa Crossover zvinogoneka kana rave majini dziri mu nonhomologous okutodza. Cytological hwaro zvakadaro batanidzo uye apiwa - meiosis uye muchangosangana. Mendel akacherechedza kuti kudaro kusakarongeka majini peya nomumwe hunhu nhaka pasina mumwe, norusununguko kuitwa kukabatanidzwa mune zvose zvinobvira mubatanidzwa (akazvimirira nhaka).

All mifananidzo nhaka kuti Mendel akasiyira kuroorwa uye vaviri-chemasanganiswa kuberekesana, hunhu anofambidzana zvikuru kunzwisisa. Saka, poligibridnoe takayambuka kunoitika apo zvinenge zviri kutora matatu kana kupfuura Achisiyanisa anokudzwa ichi zvinhu. At moyo Fusion iyi gametes uye redistribution yokugara mashoko ndiyo mitemo kugaya uye pasina nhaka.

Kubva pane zvataurwa, isu kugumisa kuti vaviri-chemasanganiswa Crossover - iri Chokwadi, vaviri vakazvimiririra-richisvika vanhuwo achayambuka, apo mumwe nzira chiratidzo inocherechedzwa nhoroondo (monohybrid). Izvi ichokwadi kuti zvinomera uye mhuka.