Yuav ua li cas yog ob replication forks?
Yuav ua li cas yog ob replication forks?

Video: Yuav ua li cas yog ob replication forks?

Video: Yuav ua li cas yog ob replication forks?
Video: Tupao Xiong & Nhia Chang - Kuv Tsis Paub Yuav Ua Li Cas (Original) 2024, Hlis ntuj nqeg
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Cov replication diav rawg yog ib struct daim ntawv nyob rau hauv ntev helical DNA thaum lub sij hawm DNA rov ua dua . Nws yog tsim los ntawm helicases, uas rhuav cov hydrogen bonds tuav lub ob DNA txuas ua ke nyob rau hauv lub helix. Cov qauv tsim muaj ob branching "prongs", txhua tus ua los ntawm ib txoj hlua DNA.

Kuj nug, 2 replication forks ua dab tsi?

Ob replication forks tsiv nyob rau hauv opposite lus qhia ntawm ib ncig chromosome. Ib qho chaw ua haujlwm ntawm DNA rov ua dua txav mus zuj zus raws cov qauv DNA molecule, tsim Y-zoo li DNA qauv hu ua a replication diav rawg : ob txhais caj npab ntawm txhua Y (ntxiv)

Ib yam li ntawd, lwm lub npe rau replication fork yog dab tsi? Cov replication diav rawg yog ib qho chaw nquag heev uas DNA rov ua dua siv qhov chaw. Nws yog tsim thaum DNA helicase unwinds ob chav helix qauv ntawm DNA. Cov replication diav rawg zoo li a diav rawg nyob rau hauv txoj kev uas yog tsim los ntawm ib tug thawj strand thiab ib tug lagging strand ntawm DNA.

Ib tug kuj tseem nug, vim li cas ob daim ntawv theej ntawm cov enzyme tsim nyog ntawm txhua qhov rov ua dua tshiab?

Replication Fork . Thaum DNA * rov ua dua DNA ob helix yuav tsum unwind thiab cais kom DNA polymerase cov enzymes siv tau txhua ib strand raws li ib tug template rau lub synthesis ntawm ib tug tshiab ob strand. Ib tug xov tooj ntawm pab proteins tiv thaiv cov strands los ntawm rov los ua ke ua ntej rov ua dua ua tiav.

Dab tsi yog replication npuas thiab replication forks?

A replication npuas yog ib qho chaw tsis muaj mob thiab qhib thaj tsam ntawm DNA helix qhov twg DNA rov ua dua tshwm sim. Helicase unwinds tsuas yog ib feem me me ntawm DNA ntawm ib lub sij hawm nyob rau hauv ib qho chaw hu ua keeb kwm ntawm rov ua dua . Ob sab ntawm txhua npuas (qhov twg nws mus ntawm zipped mus rau unzipped) hu ua replication forks.

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