Izakhi zofuzo - incazelo yombono, izindlela zokuxhumana

I-genotype ihlanganisa inqwaba yezinhlobo ezihlukahlukene zegciwane, okwenza kube yinto eyodwa kuphela. Umsunguli wezakhi zofuzo, uMendel, emibhalweni yakhe uchaze ukuthi wathola kuphela ukuthi kungenzeka ukuthi ukusebenzisana kwezakhi zohlobo lwe-allelic - uma kunamandla okubusa (ukubusa) kwesinye sezintambo, kuyilapho lesibili sihlala siphambene ngokuphelele (okungukuthi, okungukuthi, akubandakanyi Ukuxhumana). Kodwa uma sithi ukubonakaliswa kwe-genotypic yezakhi zofuzo (kwangaphandle, ukubukeka okubonakalayo) akukwazi ukuncika kuphela kumbe owodwa noma kwezimbili zezakhi zofuzo, ngoba kuwumphumela wokusebenzisana kwawo wonke uhlelo.

Empeleni, amaprotheni nama-enzyme asebenzisana, hhayi ama-genes.

Ezenzweni zezofuzo , izinhlobo ezimbili kuphela zokusebenzisana kwezakhi zofuzo zihlukile - okokuqala ukusebenzisana kwezakhi zofuzo ze-allelic, okwesibili, ngokulandelanayo, okungezona zonke. Kudingekile kuphela ukuqonda ohlangothini lwezinto eziphathelene nalolu daba, ngoba akuyona yonke imibono evela encwadini yokuxhumana, kepha amaprotheni ahlanganiswa ngokwehlelo oluthile kwi- cytoplasm yamaseli, futhi inani lala maprotheni lilinganiswa ezigidini. Lolu hlelo ngokwalo, lapho amaprotheni azokwenziwa khona, futhi ngenxa yalokho, ukuxhumana kwabo okuqhubekayo kuzokhula, kufakwe emajeni anikezwa yimilayezo yangaphandle, abe ngama-chromosomes amaseli (ama-organelle amangqamuzana e-ultrascopic).

Yiziphi izakhi ezibizwa ngokuthi ama-alleles?

Izakhi zofuzo ze-allelic yizakhi zofuzo ezihlala "ezindaweni" ezifanayo (noma i-loci) kuma-chromosomes. Yonke imvelo ephilayo inezinhlobo ze-allelic ezibili. Ukusebenzisana kwezinhlobo ze-allelic kungenzeka ngezindlela eziningana, ezibizwa ngokuthi: i-codomination, i-overdominance, i-dominance ephelele nephelele.

Izakhi zofuzo ezinama-allelic zisebenzisana nomgomo wokubusa okuphelele uma kwenzeka ukuthi isenzo sofuzo esiphezulu sivimbela ngokuphelele isenzo sofuzo oludlulayo. Ukubusa okungaphelele kungabizwa ubuhlobo lapho isakhi sofuzo esinqunyiwe sichithwa ngokungathí sina futhi sithatha, ngaphandle kokuncane, ukubamba iqhaza ekwakheni izici ze-phenotypic.

Ukubambisana kubonakala lapho izakhi ze-allelic zibonisa izindawo zabo ngokuzimela. Mhlawumbe isibonelo esivela kunazo zonke se-codomination yisistimu yegazi le-ABO, lapho izici zombili ze-A no-B zisebenza ngokuzimela.

Ukweqa ngokweqile ukunyuka kwekhwalithi yemibonakaliso ye-phenotypic yesakhi esiyinhloko uma kwenzeka "ngokubambisana" nokunciphisa ngokweqile. Okungukuthi, uma kunezifo zomzimba ezi-2 ezithinta izidakamizwa ezilodwa , zibonakala zimbi kakhulu kunegesi elidumile, "elihlangene" nesakhi sofuzo.

I-Allelism eminingi

Njengoba kushiwo ngaphambili, zonke izidalwa eziphilayo zingaba nezakhi ezimbili ze-allelic kuphela, kodwa kungenzeka kube nezinselele ezingaphezu kwezingubili - lesi simo sibizwa ngokuthi yi-allelicism eminingi. Yisho masinyane ukuthi i-alleles eyodwa kuphela ibonisa izimpawu ze-phenotypic, okungukuthi, ngenkathi umsebenzi othile, abanye bephumula.

Ama-alleles njalo ajwayelekile (afana) ahlobene nokuthuthukiswa nokubonakaliswa kwesici esifanayo, kodwa ahluke kwizinga lokubonakaliswa kwalo. Futhi, izintambo eziningi zitholakala ezinhlobonhlobo zezindlela zokusebenzelana kwezakhi zofuzo. Lokhu kungukuthi, nakuba banomthwalo wesici esifanayo, kodwa, okokuqala, ubonise ngezindlela ezahlukene, futhi okwesibili, ngosizo lwezindlela ezihlukahlukene (ukuphelela okuphelele, okungaphelele, njalonjalo).

Kubonakala sengathi kungani ukudideka okunjalo? Kuyinto elula - eyodwa kuphela yezinhlobo ze-homologous alleles ingangena esakhiweni segciwane lesidalwa esiphilayo, kodwa enye yezinto ezikhona kakade isinqunywe icala. Kungenxa yokuthi ukuhlukahluka kwezinto eziphilayo ezidlala indima enkulu ekuziphendukeni kwezinto eziphilayo zifinyeleleka.