Ukwahluka Combinative nokubaluleka kwayo mvelo

Ukwahluka Combinative sisesona sizathu lweyantlukwano intraspecific zonke izinto eziphilayo. Kodwa olu hlobo ukuguqulwa yemfuza kukhokelela kuphela ukuyilwa zizifundo ezintsha uphawu kakade. Yaye Ukwahluka combinative kunye neendlela zayo musa ukuba yimbonakalo imidibaniso gene bohluke kuzo ngokupheleleyo. Ukuvela Iipropati ezintsha ngokupheleleyo ngenxa kwezi nguqu-gene ezahlukeneyo, kunokwenzeka kuphela xa kwimeko utshintsho intraspecific mutational.

Ukwahluka Combinative emiselwe uhlobo inkqubo okuzala. Ngokuba lo hlobo ukuguqulwa yemfuza imbonakalo uphawu genotypes ezintsha ngokususela imixube zemfuza elalisandul 'ukusekwa. Ukwahluka Combinative kubonakala sele isigaba ukuyilwa gametes (iiseli intsholongwane). Ngaphezu koko, ngo kwiseli nganye enjalo imelwe chromosome homologous enye kuphela ukusuka kwisibini ngasinye. Luphawulwa yinto yokuba zofuzo kuwa kwiseli intsholongwane ngokungakhethiyo, apho gametes enyameni omnye zinokwahluka ngokwaneleyo kakhulu kwi gene elimisiweyo. Akubonakali ukuba naluphi na utshintsho kubunjani eekhemikhali yenethiwekhi ngqo yolwazi zamafa.

Ngoko ke, akukho lula ukumisela combinative kubangelwa iindidi recombination zofuzo sele zikhona kwiseti chromosome. Olu hlobo ukuguqulwa yemfuza kwakhona ukuba udibaniso kunye notshintsho chromosome futhi isakhi izakhiwo. Imithombo combinative Ukwahluka sisenokuba kukuphela iinkqubo ezithe zenzeka ngexesha ukunciphisa kwicandelo iseli (meiosis) kunye isichumiso.

Esezantsi (lincinci) unit recombinations ezahlukeneyo izinto ilifa, abangele ukuyilwa lwendibaniso gene entsha, ebizwa recon. recon nganye elivumelana nucleotides ezimbini (izinto zokwakha nucleic acid) kwi kabini-ndixakene iimolekyuli DNA kunye nucleotide olunye, xa kufikwa isakhiwo iintsholongwane nucleic-balahleke single. Recon ayikho liyohluleka xa uwelile (inkqubo yotshintshiselwano phakathi bafundelane ngezibini zofuzo homologous ngexesha conjugation) kwaye zonke iimeko ezidluliselwa kuzo ngokupheleleyo.

Ukwahluka Combinative phakathi kwiiseli eukaryotic ngeendlela ezintathu:

1. recombination zeemvelo kwinkqubo kokuwela-over, apho zofuzo akhiwa ukuba imixube emitsha alleles.
2. usasazeko Independent random zofuzo ngexesha anaphase okokuqala kwicandelo inyathelo meiotic, apho bonke gamete afumane iimpawu zabo yemfuza.
3. Casual iiseli ehlangabezana intsholongwane ngexesha isichumiso.

Ngoko ke, ngokusebenzisa ezi ndlela zintathu combinative Ukwahluka elilodwa ngasinye seli kuyilwa yi ezo gametes, unenxaxheba neseti ngokupheleleyo yolwazi yemfuza. Ukuba iinguqulelo ezinjalo ilifa ucacisa iyantlukwano enkulu phakathi kweentlobo. recombination Genetic kubaluleke kakhulu ukuba nasekusungulweni naluphi na uhlobo, njengoko lwenziwa iintlobo nakumawakawaka ezithunywa genotypes. Oku kunika nayiphi ukungafani yabemi. Imbonakalo eziphilayo, sanikwa iimpawu zayo ngamnye, kugqiba ukusebenza eliphezulu yokukhethwa zendalo, bamnika ithuba lokubaleka kuphela udibaniso iyimpumelelo iimpawu zamafa. Ngenxa sokubandakanya eziphilayo ezintsha inkqubo ekuzaleni, ukwakhiwa yemfuza ziqhubela phambili ukuphucuka.