Qhov sib txawv tseem ceeb ntawm kev sib txuas thiab kev tawm tsam yog qhov kev sib txuas yog hais txog kev sib txuas ntawm ob qho tseem ceeb lossis ob qho kev thim rov qab thaum kev tawm tsam yog hais txog kev sib txuas ntawm cov tseem ceeb alleles nrog cov alleles recessive.
Raws li nws qhov kev sim, Gregor Mendel tau hais txog peb txoj cai ntawm kev txais qub txeeg qub teg: txoj cai ntawm kev tswj hwm, txoj cai ntawm kev cais thiab txoj cai ntawm kev ywj pheej. Txoj cai lij choj ntawm kev ywj pheej hais tias cov noob rau qhov sib txawv ntawm qhov sib txawv ntawm nws tus kheej ntawm ib leeg thaum lub sij hawm tsim gamete. Txawm li cas los xij, qee qhov kev sim qhia tsis ua haujlwm hauv kev ywj pheej ntawm cov noob. Thaum lub sij hawm qhov kev xeem hla, qhov kev cia siab piv tsis tau pom. Qhov no yog vim kev sib txuas ntawm caj ces. Coupling thiab repulsion yog ob yam sib txawv ntawm kev sib txuas. Coupling yog hais txog kev sib txuas ntawm ob qho tseem ceeb los yog ob qho kev ua tsis tau zoo thaum kev tawm tsam yog hais txog kev sib txuas ntawm cov tseem ceeb alleles nrog cov alleles recessive.
Kev sib txuas yog dab tsi?
Coupling yog qhov sib txuas ntawm ob qho tseem ceeb ntawm ob lub noob nyob rau hauv ib chromosome thiab ob lub recessive alleles ntawm ob lub noob hauv lwm homologous chromosome. Ntawm no, tseem ceeb alleles ntawm cov noob muaj nyob rau hauv ib tug chromosome, thaum lawv recessive alleles muaj nyob rau hauv lwm yam chromosome. Cov caj ces txuas no qhia cis kev npaj. Nws tuaj yeem ua piv txwv li AB/ab.
Daim duab 01: Kev sib txuas ua ke
Ib tug chromosome nqa AB thiab lwm tus yog ab. Qhov kev sib txuas ntawm lub cev ntawm cov alleles tseem ceeb thiab nruab nrab ntawm cov alleles recessive tiv thaiv lawv txoj kev ywj pheej thaum lub sij hawm tsim gamete. Dominant alleles nyiam nyob ua ke. Ib yam li ntawd, recessive alleles kuj tseem nyob ua ke thaum lub sij hawm gamete tsim.
Kev ntxub ntxaug yog dab tsi?
Repulsion yog lwm yam ntawm kev sib txuas uas txawv ntawm kev sib txuas. Nyob rau hauv repulsion, dominant alleles los yog recessive alleles los ntawm cov niam txiv sib txawv, thiab lawv nyiam nyob sib cais. Ntawm no, ib tug niam txiv chromosome nqa ib qho tseem ceeb thiab ib qho recessive allele thaum lwm tus chromosome nqa ob qho alleles (dominant thiab recessive alleles). Nws tuaj yeem ua piv txwv li Ab/aB.
Daim duab 02: Kev Ua Phem Txhaum Cai
Ib qho tseem ceeb allele yog txuas nrog lub recessive allele ntawm cov noob thib ob. Hom kev npaj noob no hu ua trans arrangement.
Dab tsi yog qhov zoo sib xws ntawm Coupling thiab Repulsion?
- Kev sib txuas thiab kev tawm tsam yog ob yam ntawm kev sib txuas.
- Lawv coj tus cwj pwm tawm tsam Mendel txoj cai ntawm kev ywj pheej.
Qhov txawv ntawm Kev Coupling thiab Repulsion yog dab tsi?
Nyob hauv kev sib txuas, muaj kev nyiam nyob hauv cov alleles tseem ceeb nyob ua ke; muaj ib tug nyiam nyob rau hauv recessive alleles nyob ua ke. Ntawm qhov tod tes, nyob rau hauv repulsion, ob tug xws li dominant alleles los yog ob tug recessive alleles los ntawm cov niam txiv sib txawv, thiab lawv nyiam nyob sib cais. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm kev sib txuas thiab kev tawm tsam. Qhov pom kev sib piv hauv kev sib txuas yog 7: 1: 1: 7 thaum qhov sib piv ntawm repulsion yog 1: 7: 7: 1. Ntxiv mus, coupling yog ib hom cis kev npaj, thaum repulsion yog ib hom kev hloov pauv.
Cov infographic hauv qab no qhia ntau qhov kev sib piv ntsig txog qhov sib txawv ntawm kev sib txuas thiab kev tawm tsam hauv daim ntawv tabular.
Summary – Coupling vs Repulsion
Coupling thiab repulsion yog ob yam ntawm cov noob txuas. Kev sib txuas yog qhov muaj ob qho tseem ceeb ntawm ob lub noob ntawm tib chromosome (AB). Cov noob caj ces tseem tshuav ntawm ob lub noob muaj nyob ntawm lwm cov chromosome (ab). Yog li ntawd, cov tseem ceeb ntawm cov noob caj noob ces yuav nyob ua ke. Repulsion yog muaj cov noob tseem ceeb ntawm ob homologous chromosomes (Ab/aB). Yog li ntawd, dominant alleles lossis recessive alleles uas los ntawm cov niam txiv sib txawv yuav nyob sib cais. Yog li, qhov no yog cov ntsiab lus ntawm qhov sib txawv ntawm kev sib txuas thiab kev tawm tsam.
