Qhov Tseem Ceeb Qhov txawv - Dominance vs Codominance
Lub tswv yim ntawm kev tswj hwm tau qhia los ntawm Gregor Mendel hauv xyoo 1865 tom qab ua tau yim xyoo ntawm kev sim nrog cov txiv laum huab xeeb. Mendel tau piav qhia tias cov noob muaj ib khub ntawm alleles thiab cov xeeb ntxwv tau txais ib qho allele los ntawm leej niam, thiab lwm yam allele los ntawm leej txiv thiab cov cwj pwm tau dhau los ntawm ib tiam mus rau tiam tom ntej. Dominance thiab codominance yog kev sib raug zoo ntawm alleles ntawm cov noob thaum qhia cov phenotypes. Qhov sib txawv tseem ceeb ntawm dominance thiab codominance yog tias dominance yog qhov cuam tshuam ntawm ib qho allele tshaj li lwm tus allele thaum cov noob nyob rau hauv heterozygous lub xeev thaum lub codominance yog qhia txog cov teebmeem ntawm ob leeg alleles ntawm nws tus kheej yam tsis muaj kev sib xyaw hauv heterozygous xeev.
Dominance yog dab tsi?
Dominance yog lub tswv yim tseem ceeb uas siv los ntawm Gregor Mendel los piav txog txoj kev xav ntawm kev qub txeeg qub teg. Ib lub noob paub tias muaj ob lub alleles: ib qho tseem ceeb allele thiab ib qho allele recessive. Dominance yog ib hom kev sib cuam tshuam ntawm allele hauv lub xeev heterozygous, nyob rau hauv uas ib tug allele ntawm ib tug noob yog hais tias tag nrho thiab cov nyhuv ntawm lub thib ob allele yog masked, uas ua rau ib tug phenotype uas qhia txog tus cwj pwm tseem ceeb. Cov allele uas tau hais tawm yog lub npe hu ua tus tseem ceeb allele thaum lub allele uas raug kev hem thawj yog hu ua recessive allele ntawm cov noob. Yog hais tias tus allele tseem ceeb, ib qho tseem ceeb allele yog txaus los qhia qhov tseem ceeb ntawm cov xeeb ntxwv.
Gregor Mendel tau piav qhia txog txoj cai tswjfwm raws li, "Ib yam kabmob uas muaj lwm hom kabmob ntawm cov noob yuav qhia txog daim ntawv uas tseem ceeb". Thaum ob tus neeg nrog heterozygous alleles hla nrog ib leeg, nws tsim cov phenotypes tseem ceeb thiab rov ua dua hauv 3: 1 piv.
Daim duab 01: Ua tiav kev tswj hwm
Codominance yog dab tsi?
Codominance yog qhov qhia txog qhov cuam tshuam ntawm ob qho tib si ntawm nws tus kheej hauv ib qho phenotype. Nws yog ib hom kev sib raug zoo ntawm alleles ntawm cov noob. Nyob rau hauv heterozygous, ob qho tag nrho alleles qhia tag nrho thiab qhia cov teebmeem ntawm allele hauv cov xeeb ntxwv ntawm nws tus kheej. Tsis yog allele suppresses cov nyhuv ntawm lwm tus nyob rau hauv codominance. Qhov kawg phenotype tsis yog qhov tseem ceeb thiab tsis muaj zog. Nws yog tsim los ntawm kev sib xyaw ua ke ntawm ob qho tib si. Ob leeg alleles tau tshwm sim hauv phenotype yam tsis muaj kev sib xyaw ntawm tus kheej cov teebmeem. Nyob rau hauv qhov kawg phenotype, cov teebmeem ntawm ob leeg alleles tuaj yeem paub meej meej hauv qhov xwm txheej codominance.
ABO cov ntshav pab pawg tuaj yeem piav qhia ua piv txwv rau kev sib koom ua ke. Allele A thiab allele B yog codominant rau ib leeg. Yog li cov ntshav AB tsis yog A lossis B. Nws ua haujlwm raws li pawg ntshav cais vim yog kev sib koom ua ke ntawm A thiab B.
Daim duab 02: Codominance hauv Rhododendron
Dab tsi yog qhov txawv ntawm Dominance thiab Codominance?
Dominance vs Codominance |
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| Dominance yog kev sib raug zoo ntawm ob qho alleles uas tseem ceeb allele suppresses cov nyhuv ntawm recessive allele thaum lub sij hawm qhia. | Codominance yog ib hom kev tswj hwm hauv heterozygous uas ob leeg alleles ntawm nws tus kheej qhia cov txiaj ntsig ntawm allele ntawm qhov kawg phenotype. |
| Tus yam ntxwv ntawm Phenotype | |
| Kev cuam tshuam ntawm cov tseem ceeb allele yog pom nyob rau hauv phenotype. | Kev cuam tshuam ntawm ob qho tag nrho yog qhov tseeb hauv kev sib koom ua ke. |
| Qhia tawm Alleles | |
| Ib qho allele qhia tag nrho thaum lwm tus allele raug txwv. | Ob leeg alleles tau qhia tag nrho hauv lub xeev codominance. |
| Masking Effect | |
| Ib qho allele tag nrho npog cov nyhuv ntawm lwm tus allele. | Tsis yog allele ua lub npog qhov ncauj rau lwm tus. |
| Phenotype | |
| Phenotype yog dominant. | Phenotype tsis yog qhov tseem ceeb lossis tsis txaus. |
| Kev ywj pheej ntawm Allele | |
| Dominant allele ua haujlwm ntawm nws tus kheej. | Ob leeg alleles ua haujlwm ntawm nws tus kheej thiab sib npaug. |
| Quantitative Effect | |
| Quantitative effect is tam sim no. | Cov txiaj ntsig ntau yog tsis tuaj. |
Summary – Dominance vs Codominance
Dominance thiab codominance yog ob hom kev sib raug zoo uas pom nyob rau hauv lub xeev heterozygous. Dominance yog qhov teeb meem nyob rau hauv uas tseem ceeb allele yog tag nrho qhia thaum suppressing lub recessive allelic nyhuv ntawm phenotype. Codominance yog qhov xwm txheej uas ob leeg alleles ua haujlwm ntawm nws tus kheej thiab qhia lawv cov teebmeem hauv phenotype yam tsis muaj kev sib xyaw ua ke. Qhov no yog qhov txawv ntawm dominance thiab codominance. Nyob rau hauv dominance, dominant allele yog dominated thaum nyob rau hauv codominance tsis yog allele dominated.
