Video: Li cas ywj siab assortment nce genetic ntau haiv neeg?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Genetic ntau haiv neeg yog nce los ntawm ywj siab assortment ( noob tau txais kev ywj pheej ntawm ib leeg) thiab hla thaum meiosis. Thaum lub sij hawm meiosis, chromosomes (uas pom nyob rau hauv khub) sib pauv loj feem ntawm lawv cov molecules, ua rau caj ces cov khoom yuav tsum sib xyaw ntawm lawv.
Nyob rau hauv no hais txog, ua li cas ywj siab assortment muaj feem xyuam rau genetic ntau haiv neeg?
Meiosis thiab Genetic Variation . Thaum cov hlwb sib faib thaum lub sij hawm meiosis, homologous chromosomes raug faib randomly faib thaum lub sij hawm anaphase I, sib cais thiab cais. ywj siab ntawm ib leeg. Qhov no hu ua ywj siab assortment . Nws ua rau gametes uas muaj qhov sib xyaw ua ke ntawm chromosomes.
Qhov thib ob, yuav ua li cas random fertilization ntxiv rau genetic variation? Cov random xwm ntawm fertilization ntxiv rau noob caj noob ces variation tshwm sim los ntawm meiosis. Txhua tus phev tuaj yeem fuse nrog txhua lub qe. Ib tug zygote tsim los ntawm mating ntawm ib tug poj niam thiab txiv neej muaj ib tug tshwj xeeb caj ces tus kheej. Hla mus ntxiv ntau dua kev hloov pauv rau qhov no.
Xav txog qhov no, yuav ua li cas hla kev nce kev sib txawv ntawm caj ces?
Hla mus , los yog recombination, yog kev sib pauv ntawm chromosome ntu ntawm nonsister chromatids hauv meiosis. Hla mus tsim tshiab ua ke ntawm noob nyob rau hauv gametes uas tsis pom nyob rau hauv ob niam txiv, contributing rau muaj ntau haiv neeg.
Dab tsi yog qhov tshwm sim ntawm kev hla dhau thiab kev ywj pheej assortment hauv meiosis?
Hla - dhau yog kev sib pauv ntawm cov khoom siv caj ces ntawm homologous chromosomes. Nws tshwm sim hauv kev sib txuas tshiab ntawm cov noob ntawm txhua tus chromosome. Thaum cov hlwb sib faib thaum lub sijhawm meiosis , homologous chromosomes random faib rau cov ntxhais cell, thiab sib txawv chromosomes cais. ywj siab ntawm ib leeg.
Pom zoo:
Yuav ua li cas yog tsis muaj ntau haiv neeg?
Yog tias tsis muaj kev hloov pauv caj ces, cov pej xeem tsis tuaj yeem hloov pauv hauv kev teb rau kev hloov pauv ib puag ncig thiab, vim li ntawd, yuav ntsib kev pheej hmoo ntawm kev ploj tuag. Piv txwv li, yog tias cov pej xeem raug tus kab mob tshiab, kev xaiv yuav ua rau cov noob tiv thaiv kab mob yog tias lawv muaj nyob hauv cov pej xeem
Lub luag haujlwm ntawm carbon nyob rau hauv molecular ntau haiv neeg ntawm lub neej yog dab tsi?
Cov pa roj carbon monoxide yog qhov tsis sib xws hauv nws lub peev xwm los tsim cov loj, complex, thiab ntau hom molecules. Cov proteins, DNA, carbohydrates, thiab lwm yam molecules uas paub qhov txawv ntawm cov khoom muaj sia los ntawm cov khoom siv tsis muaj sia yog txhua tus muaj cov pa roj carbon atoms sib txuas rau ib leeg thiab rau cov atoms ntawm lwm cov khoom
Vim li cas meiosis tseem ceeb rau ntau haiv neeg?
Meiosis yog ib qho tseem ceeb vim nws ua kom txhua yam kab mob uas tsim los ntawm kev sib deev muaj tus lej ntawm chromosomes. Meiosis kuj tsim kev hloov pauv caj ces los ntawm txoj kev ntawm cov txheej txheem recombination
Dab tsi theem ntawm meiosis ua ywj siab assortment tshwm sim?
Thaum lub sij hawm meiosis, kev ywj pheej assortment yuav ua ntej thiab tom qab ntawd hla yuav ua. Tsis yog, kev ywj pheej assortmentoccurs tom qab hla dhau. Hla dhau tshwm sim hauv prophase Iwhile ywj siab assortment tshwm sim hauv metaphase I andanaphase I
Yuav ua li cas tsis txawj nyeem ntawv yog txaus ntshai rau ib tug kev ywj pheej haiv neeg?
Kev tsis nyeem ntawv yog qhov txaus ntshai rau cov neeg ywj pheej vim tias muaj pes tsawg tus neeg muaj cai xaiv tsa uas tsis paub ntawv yog nyob deb txaus los mus pov npav. Qhov no tuaj yeem ua rau kev xaiv tsa tus thawj tswj hwm uas tsis yog kev nom kev tswv zoo li lwm tus neeg sib tw