Dab tsi yog tsim thaum kawg ntawm DNA replication?
Dab tsi yog tsim thaum kawg ntawm DNA replication?

Video: Dab tsi yog tsim thaum kawg ntawm DNA replication?

Video: Dab tsi yog tsim thaum kawg ntawm DNA replication?
Video: Larva to adult: 金魚の発生学実験#04: 仔魚から成魚へ Ver.2022 0605-GF04 2024, Kaum ib hlis
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Cov xaus ntawm niam txiv strands muaj dua DNA cov kab ke hu ua telomeres. Thaum ua tiav, niam txiv strand thiab nws complementary DNA strand coils mus rau hauv qhov paub txog ob lub helix zoo. Hauv kawg , rov ua dua ua ob DNA molecules, txhua tus nrog ib txoj hlua los ntawm niam txiv molecule thiab ib txoj hlua tshiab.

Ib yam li ib tug yuav nug, qhov kawg ntawm DNA replication yog dab tsi?

Cov Qhov tshwm sim ntawm DNA replication yog ob DNA molecules muaj ib tug tshiab thiab ib tug qub saw ntawm nucleotides. Qhov no yog vim li cas DNA replication yog piav raws li ib nrab-conservative, ib nrab ntawm cov saw yog ib feem ntawm thawj DNA molecule, ib nrab yog brand tshiab.

Qhov thib ob, telomerase yog dab tsi hauv DNA replication? Qhov kawg ntawm linear chromosomes, hu ua telomeres, tiv thaiv cov noob los ntawm kev tshem tawm thaum cov hlwb txuas ntxiv mus. Cov telomerase enzyme txuas mus rau qhov kawg ntawm chromosome; complementary bases rau RNA template yog ntxiv rau ntawm 3' kawg ntawm lub DNA txoj hlua.

Ua raws li qhov no saib, dab tsi yog DNA replication txheej txheem?

DNA replication cov kauj ruam . Muaj peb lub ntsiab cov kauj ruam rau DNA replication : pib, elongation, thiab termination. Txhawm rau kom haum rau hauv lub cell lub nucleus, DNA yog ntim rau hauv nruj coiled qauv hu ua chromatin, uas loosens ua ntej rov ua dua , tso cai rau lub cell rov ua dua machinery nkag mus rau lub DNA strands.

Yuav ua li cas yog tias DNA tsis rov ua dua?

S theem cyclins tswj kev nce qib ntawm lub voj voog ntawm tes thaum lub sijhawm DNA replication . Yog ib cell tsis muaj kom luam nws cov chromosomes los yog muaj yog kev puas tsuaj rau DNA , CDK yuav tsis yog qhib lub S theem cyclin thiab lub cell yuav tsis yog nce mus rau theem G2.

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