Video: Dab tsi yog seem ntawm DNA raug theej hu ua?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
DNA replication yog tus txheej txheem uas DNA ua a luam ntawm nws tus kheej thaum lub sij hawm faib cell. Thawj kauj ruam hauv DNA replication yog mus 'unzip' ob chav helix qauv ntawm lub DNA ? molecule. Kev sib cais ntawm ob qho tib si strands ntawm DNA tsim 'Y' duab hu ua ib replication 'fork'.
Tsuas yog li ntawd, DNA tau theej hauv lub cell li cas?
Cells Yuav Replicate Lawv DNA Precisely. Replication yog txheej txheem los ntawm ob-stranded DNA molecule yog luam tsim kom muaj ob qho tib si DNA molecules. DNA replication yog ib qho ntawm cov txheej txheem yooj yim tshaj plaws uas tshwm sim hauv ib cell . Yuav kom ua tiav qhov no, txhua txoj hlua ntawm cov uas twb muaj lawm DNA ua raws li ib tug template rau replication.
Ib yam li ntawd, cov strand ntawm DNA twg yog transcribed rau hauv mRNA? Lub stretch ntawm DNA tau sau rau hauv RNA molecule hu ua a kev sau ntawv unit thiab encodes yam tsawg kawg ib gene. Yog hais tias lub gene encodes ib tug protein, lub kev sau ntawv tsim cov tub txib RNA ( mRNA ); tus mRNA , nyob rau hauv lem, ua hauj lwm raws li ib tug template rau cov protein synthesis los ntawm kev txhais lus.
Ua li no, vim li cas DNA tau theej rau hauv tus tub txib?
Transcription yog txheej txheem uas cov ntaub ntawv hauv ib strand DNA tau theej rau hauv ib new molecule ntawm tus tub txib RNA (mRNA). Meanwhile, mRNA yog piv rau ib daim ntawv luam ntawm phau ntawv siv vim nws nqa tib cov ntaub ntawv raws li DNA tab sis tsis yog siv rau kev khaws cia ntev thiab tuaj yeem tawm ntawm lub nucleus dawb.
Cov txheej txheem twg yog ib feem ntawm kev sau ntawv?
Kev sau ntawv yog cov txheej txheem uas DNA tau theej ( luam tawm ) mus rau mRNA, uas nqa cov ntaub ntawv xav tau rau kev tsim cov protein. Kev sau ntawv yuav tshwm sim nyob rau hauv ob kauj ruam dav. Ua ntej, ua ntej tus xa xov RNA yog tsim, nrog kev koom tes ntawm RNA polymerase enzymes.
Pom zoo:
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