Yintoni na le crossover gqith-amabini

Imithetho yelifa Mendel for monohybrid umnqamlezo ezisagcinwe kwimeko ngakumbi esimbaxa gqith-mbini. Kule hlobo fom umzali intsebenziswano kwahluka ngambini ezimbini iimpawu okungafani.

Cinga nje ngomzekelo ka-Mendel dihybrid umnqamlezo kunye nokuqinisekisa nemithetho. Awela iindidi ezimbini ertyisi: ngeentyatyambo ezimhlophe kunye undi eqhelekileyo kunye neentyatyambo purple umphetho evuthelweyo. Bonke abantu-isizukulwana yokuqala iintyatyambo eziqhelekileyo emhlophe kunye phehla. Kule sigqiba ukuba umbala omhlophe (zibonakaliswe yi C) kwaye ubude yesiqhelo (bhala E) - kuba lisalawula features umbala omsobo (s) kunye phehla elongate (e) - sofuzo. Xa self-uvuvuzelo besizukulwana sokuqala utyalayo sahlukana. Ngenxa gca zenza scheme ukuwela.

cross lokuqala: P1 x CCEE CCEE

G 2Ss and 2Ee

F1 CCEE

Ukusukelwa yesibini (selfing ibhastile F1) P2 x CCEE CCEE. umnqamlezo Dihybrid iya kuba iintlobo 16 zygotes. gamete nganye iya kuba nommeli omnye ngababini gene ne-P-and E-E ngababini. Xa oku gene C kunye amathuba alinganayo zinokudityaniswa kunye E okanye e nabo, kwaye esinokudibanisa E okanye nge Amaxwebhu CCEE ngenxa gqith rhoqo alinganayo kweentlobo gamete 4: .. CE, uGenubhati, Ce, ce. Obedin kunye, ukwenza izinto ezinjalo: 9 kunye Corolla eqhelekileyo emhlophe, 3 ezimhlophe elongate phehla 3 kunye magenta yesiqhelo undi kunye magenta 1 kunye udini evuthelweyo.

Xa isizukulwana wesibini ewela ibhastile nto ngaphandle, iifomu ngaphandle efanayo ngabazali, eemilo kwakheka ukuhlanganiswa entsha zabalinganiswa (combinative okanye Ukwahluka yemfuza). Le meko ludlala indima ebalulekileyo ekudalweni nasekusungulweni izivuno imixube emitsha iimpawu encomekayo. Kwakhona ngenkuthalo ezisetyenziswa nokuzalela, apho kweenkomo izityalo kunye nezilwanyana zonke iintlobo eziphuculweyo iintlobo kwenza kube lula ukuba ukwazisa iintlobo ezintsha.

Inani phenotypes e F2 lingaphantsi kwenani genotypes. Oku kubangelwa yinto yokuba yeemanyano gametes ezahlukeneyo anganika efanayo neempawu morphological. Ngoko ke, siye sifumane ukwahlukana phenotype - 9: 3: 3: 1.

Le crossover gqith-ezimbini kunokwenzeka ukuba zofuzo lubalaseleyo ibekwe zofuzo nonhomologous. isiseko Cytological kuza naziphi kwaye kwakhona - meiosis kunye isichumiso. Mendel waphawula ukuba loo impefumlelwano yemfuza isibini ngasinye iimpawu ilifa ngokuzimeleyo omnye komnye, ngesisa ukuba ezidityanisiweyo zonke lwendibaniso ezenzekayo (ilifa ezizimeleyo).

Zonke iipateni yelifa ukuba Mendel awawumisela abangatshatanga kunye gqith-ezimbini ukusukelwa, uphawu lwendibaniso ezimbaxa ngakumbi. Ngoko ke, poligibridnoe yokuwela kwenzeka xa eziphilayo zithathwa ukuba lo dokotela kwiinkalo ezintathu okanye okungafani ngaphezulu. Xa intliziyo le ngxubevange gametes kunye nokunikezelwa lolwazi kwezakhi imithetho yokwetyiswa elizimeleyo ilifa.

Ukususela ngasentla, sigqiba ukuba crossover gqith-mbini - kukuthi, enyanisweni, ezimbini ngokuzimeleyo-afikelele zibuko esiqhelekileyo, apho omnye umqondiso ezichaseneyo kuthathelwa ingqalelo (monohybrid). Oku kuyinyaniso ukuba izityalo kunye nezilwanyana.