Imithetho Mendel kaThixo. Imithetho imizila yemfuza

Gregor Mendel - yezityalo waseOstriya, wafunda waza wachaza nendlela lilifa. imithetho Mendel kaThixo - oku sisiseko yemfuza Ungadlala indima ebalulekileyo ekufundeni yempembelelo kwimfuza kunye nokusasazwa imikhwa zamafa.

Kulingo zabo, izazinzulu awelela iintlobo ezahlukeneyo ze-ertyisi, ezahlukeneyo ngokusekelwe enye kwenye: emthunzini umbala, agudileyo, iertyisi ukushwabana, isiqu ukuphakama. Ukongeza, isici esasenza experiments Mendel yaba ukusetyenziswa ebizwa ngokuba "imigca ezicocekileyo", ie inzala evela self-uvuvuzelo esityalo lomzali. imithetho Mendel kaThixo, amagama kunye nenkcazo emfutshane kuya kuxoxwa ngezantsi.

Iminyaka emininzi ukufunda kunye ngokucophelela ulungiselela ulingelo nge-ertyisi: iibhegi ezizodwa ngokukhusela iintyatyambo ukusuka uvuvuzelo yangaphandle, isazinzulu Austria sele iphumelele iziphumo emangalisayo ngelo xesha. Uhlalutyo olunzulu nende lwe data ukuba umphandi ukuba imithetho yofuzo, apho kamva yaziwa ngokuba "imithetho Mendel kaThixo".

Ngaphambi kokuqhubeka nenkcazelo imithetho kufuneka kwaziswe izinto ezininzi eziyimfuneko ukuze ukusiqonda isicatshulwa:

gene lwiimi - isakhi ogama iimpawu wabonakalaliswa emzimbeni. Luchazwa yi ngonobumba omkhulu: A, B Xa kokunqumla enjalo kuqwalaselwa phantsi kwemiqathango namandla, ngamanye yena usoloko ukuzibonakalisa kwimeko, ukuba isityalo umzali yesibini iyakunqunyanyiswa kwi ngobulali ubuncinane imiqondiso. Leyo engqina ukuba imithetho Mendel.

sofuzo - ukhetho kwi phenotype ayenziwanga ngayo, nangona ekhona kule kweejini. Liboniswe unobumba eyinkunzi, b.

Heterozygous - hybrid, kweejini (uluhlu genes) ogama, kukho ezibalaseleyo kunye sofuzo ukuba imfanelo ethile. (Aa ne bb)

Homozygous - hybrid ube gene kuphela lubalaseleyo okanye sofuzo abajongene mfanelo. (AA okanye bb)

Ezi zinto zilandelayo ziya kuqwalaselwa imithetho Mendel kaThixo, basebenzisane ngokufutshane.

umthetho wokuqala Mendel kaThixo, okwabizwa ngokuba umthetho ibhastile ufano kukwazi ukwakhiwa ngolu hlobo lulandelayo: ibhastile sizukulwana sokuqala, efunyenwe imigca namantshontsho enyulu zooyise kunye nezityalo koomama uye phenotypic umahluko phakathi kwento wafunda (oko kukuthi, ngaphandle). Ngamanye amazwi, bonke abantwana babe izityalo umthunzi enye iintyatyambo, isiqu ukuphakama, ngobuqhophololo okanye uburhabaxa-ertyisi. Ngaphezu koko, libonisa iimpawu phenotypically ingqinelana twatse ukuya isiseko lokuqala omnye wabazali.

Umthetho wesibini yomthetho Mendel kaThixo yocalulo okanye ufunda inzala ngxilimbela heterozygous besizukulwana sokuqala yeyokuzingca yaMaxwebhu okanye yokuzalisana kengoko iimpawu sofuzo kwaye lubalaseleyo. Kwaye ke cleavage kwenzeka ngale ndlela ilandelayo: 75% - zityalo phawu lubalaseleyo, i-25% - nge sofuzo. Ngamafutshane, ukuba izityalo umzali kufuneka ezibomvu (zimbini) kunye neentyatyambo etyheli (phawu sofuzo), isityalo intombi iya kuba iintyatyambo ebomvu 3/4, kwaye abanye - yellow.

Sesithathu, Mendel kaThixo uMthetho, ekwabizwa ngokuba nomthetho ezimeleyo lilifa, jikelele kuthetha oku kulandelayo: xa bewela homozygous isityalo ukuba emibini okanye ngaphezulu ezahlukeneyo iimpawu (ngamanye amazwi, umzekelo, phezulu lwesityalo kunye obomvu neentyantyambo (AABB) nezisezantsi lwesityalo kunye ebengezelayo iintyatyambo (aabb), wafunda imiqondiso (stem nombala kunye nobude iintyatyambo) azuze ngokuzimeleyo. ngamanye amazwi, ngenxa yokuwela ukuze izityalo abade ngeentyatyambo esimthubi (aabb) okanye obomvu ephantsi (aaBb).

imithetho Mendel kaThixo, izakuvula phakathi kwenkulungwane ye-19, emva koko kakhulu wazuza ingqalelo. Selection - Ngokusekelwe kubo, yonke yemfuza mihla, yaye emva lakhiwa. Ukongeza, imithetho Mendel kukho ubungqina iyantlukwano enkulu kweentlobo ezikhoyo namhlanje.