Gene drift: cov qauv tseem ceeb ntawm cov txheej txheem no

Gene drift: cov qauv tseem ceeb ntawm cov txheej txheem no
Gene drift: cov qauv tseem ceeb ntawm cov txheej txheem no
Anonim

Cov ntu ntawm DNA qhov twg muaj qee cov noob nyob hauv hu ua locus. Nws tuaj yeem muaj lwm yam kev hloov pauv ntawm cov ntaub ntawv caj ces - alleles. Nyob rau hauv txhua tus pej xeem muaj coob tus ntawm cov qauv no. Hauv qhov no, qhov kev faib ua feem ntawm ib qho allele hauv tag nrho cov genome ntawm cov pejxeem yog hu ua qhov zaus ntawm cov noob.

genetic drift
genetic drift

Rau qee qhov kev hloov pauv kom ua rau muaj kev hloov pauv hauv cov tsiaj, nws zaus yuav tsum siab txaus, thiab cov mutant allele yuav tsum tau kho rau txhua tus neeg ntawm txhua tiam neeg. Nrog me me ntawm nws, kev hloov pauv tsis tuaj yeem cuam tshuam txog keeb kwm kev hloov pauv ntawm cov kab mob.

Yuav kom cov allele zaus nce, qee yam yuav tsum ua - caj ces drift, tsiv teb tsaws thiab xaiv ntuj.

Gene drift yog qhov kev loj hlob tsis zoo ntawm ib qho allele nyob rau hauv kev cuam tshuam ntawm ntau yam xwm txheej uas tau ua ke thiab muaj tus cwj pwm stochastic. Cov txheej txheem no cuam tshuam nrog qhov tseeb tias tsis yog txhua tus tib neeg hauv cov pejxeem koom nrog kev yug me nyuam. Nws yog cov yam ntxwv feem ntau ntawm cov yam ntxwv lossis cov kab mob uas tsis tshua muaj, tab sis vim tsis muaj kev xaiv, muaj peev xwm muab khaws cia rau hauv ib lub genus lossis txawm tias tag nrho cov pejxeem ntawm ib qho me me rauntev. Cov qauv no feem ntau pom nyob rau hauv cov pej xeem me me, cov naj npawb ntawm cov neeg tsis pub tshaj 1000 tus neeg, vim qhov no kev tsiv teb tsaws yog tsawg heev.

Yuav kom nkag siab zoo dua cov caj ces, cov qauv hauv qab no yuav tsum paub. Nyob rau hauv rooj plaub uas lub allele zaus yog 0, nws tsis hloov nyob rau hauv lub tom ntej tiam. Yog tias nws nce mus txog 1, ces cov noob tau hais tias yuav tsum tau kho nyob rau hauv cov pej xeem. Random gene drift yog qhov tshwm sim ntawm cov txheej txheem fixation nrog ib txhij poob ntawm ib qho allele. Feem ntau, tus qauv no tau pom thaum kev hloov pauv thiab kev tsiv teb tsaws tsis ua rau muaj kev hloov pauv mus tas li hauv qhov chaw nyob.

genetic drift yog
genetic drift yog

Vim tias gene zaus tsis yog kev taw qhia, nws txo cov hom kev sib txawv thiab tseem ua rau muaj qhov sib txawv ntawm cov neeg hauv zos. Nws yog ib nqi sau cia hais tias qhov no yog counteracted los ntawm tsiv teb tsaws, nyob rau hauv uas sib txawv pawg ntawm cov kab mob pauv lawv alleles. Nws kuj tseem yuav tsum tau hais tias cov noob caj noob ces tau xyaum tsis cuam tshuam rau qhov zaus ntawm ib tus neeg cov noob hauv cov neeg coob, tab sis hauv cov pab pawg me tuaj yeem dhau los ua qhov kev txiav txim siab evolutionary. Hauv qhov no, tus naj npawb ntawm alleles hloov pauv ntau heev. Qee cov noob caj noob ces tuaj yeem ploj mus tsis tau, ua rau muaj kev tsis zoo ntawm cov noob caj noob ces.

genetic engineering yog
genetic engineering yog

Raws li piv txwv, peb tuaj yeem hais txog kev sib kis loj, tom qab ntawd kev rov kho cov pej xeem tau ua tiav ntawm kev siv nyiaj ntawm ob peb tus neeg sawv cev. Ntxiv mus, tag nrho cov xeeb leej xeeb ntxwv muaj tib genome li lawv cov poj koob yawm txwv. Kev nthuav dav ntxivallelic ntau haiv neeg tau ua kom ntseeg tau los ntawm kev xa tawm ntawm cov neeg tsim khoom lossis kev sib tw tawm sab nraud, uas ua rau muaj kev loj hlob ntawm qhov sib txawv ntawm qib noob.

Qhov kev tshwm sim loj heev ntawm cov noob caj noob ces tuaj yeem hu ua qhov tshwm sim ntawm cov pej xeem tshiab, uas yog tsim los ntawm ob peb tus neeg xwb - hu ua tus tsim nyhuv.

Nws yuav tsum tau hais tias cov qauv ntawm genome rearrangement yog kawm los ntawm biotechnology. Genetic engineering yog txheej txheem ntawm kev tshawb fawb no uas tso cai rau koj hloov cov ntaub ntawv keeb kwm yav dhau los. Nyob rau tib lub sijhawm, kev hloov pauv noob tso cai rau koj los cuam tshuam nrog cov kab mob sib kis, nrog rau muab cov kab mob tsim nyog.

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