Qhov feem pua ntawm cov xeeb ntxwv yuav yog heterozygous?
Qhov feem pua ntawm cov xeeb ntxwv yuav yog heterozygous?

Video: Qhov feem pua ntawm cov xeeb ntxwv yuav yog heterozygous?

Video: Qhov feem pua ntawm cov xeeb ntxwv yuav yog heterozygous?
Video: Saib Mis paub Poj niam (hluas nkauj) tus yam ntxwv lub siab 2024, Kaum ib hlis
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Lub Punnett square hauv qab no qhia meej tias thaum txhua tus yug, muaj yuav ua 25% txoj hauv kev uas koj muaj ib tus menyuam homozygous (AA), 50% txoj hauv kev noj qab haus huv heterozygous (Aa) tus menyuam muaj tus kabmob xws li koj thiab koj tus txij nkawm, thiab 25% muaj feem ntawm homozygous recessive (aa) tus menyuam uas tej zaum yuav kawg tuag ntawm no

Ua li no, pes tsawg feem pua ntawm cov xeeb ntxwv yuav tau txais cov phenotype recessive thaum hla ob heterozygous?

Kev piav qhia: Raws li ib txwm muaj xws li Mendelian dominance yog 2 heterozygotes rau ib tus cwj pwm ua hla ces phenotypically, 25% tawm-caij nplooj ntoos hlav yuav ua yeeb yam rov ua dua qhov zoo thaum 75% yuav ua yeeb yam tseem ceeb qhov zoo.

Tom qab ntawd, lo lus nug yog, qhov tshwm sim ntawm tau txais DD cov xeeb ntxwv yog dab tsi? Yog li ntawd rau cov niam txiv uas ob leeg muaj genotype Dd , muaj 25% qhov tshwm sim tias lawv xeeb yog DD yog 25% qhov tshwm sim tias cov xeeb yog dd , thiab 50% qhov tshwm sim tias cov xeeb yog Dd.

Ib yam li ntawd, tej zaum koj yuav nug, cov xeeb ntxwv puas yog homozygous lossis heterozygous?

Thaum muaj tseeb-loj hlob, los yog homozygous , cov tib neeg uas txawv rau ib qho kev zoo yog hla, tag nrho cov xeeb tub yuav ua heterozygous rau qhov zoo. Yog hais tias tus cwj pwm yog inherited li tseem ceeb thiab recessive, F1 xeeb tub yuav txhua tus pom tib phenotype li niam txiv homozygous rau cov tseem ceeb qhov zoo.

Tus ntoo khaub lig yuav tsim cov xeeb ntxwv heterozygous nkaus xwb?

Lwm cov noob caj noob ces dhau ntawm kev hla ob qhov tseeb-loj hlob, cov tib neeg homozygous tuaj yeem tsim cov xeeb ntxwv heterozygous. Rau piv txwv , hla lub heterozygous pea nyob rau saum toj piv txwv nrog rau homozygous dawb pea cog yuav ua rau cov xeeb ntxwv uas yog, qhov nruab nrab, 50 feem pua heterozygous thiab 50 feem pua homozygous.

Pom zoo: