DNA replication - lub ntsiab theem

Replicating DNA - deoxyribonucleic acid biosynthesis. Cov ntaub ntawv uas rau biosynthesis ntawm DNA yog adenosine, thiab guanozin- tsitidin- timidintrifosfornaya acid los yog ATP, GTP, CTP thiab TTP.

DNA replication

Biosynthesis nqa tawm nyob rau hauv lub xub ntiag ntawm thiaj li hu ua "noob" - ib tug muaj nuj nqis ntawm cov hloov ib leeg-tso tseg deoxyribonucleic acid catalyst. Lub catalyst ua raws li ib tug DNA polymerase. Qhov no enzyme yog muab kev koom tes nyob rau hauv lub mix ntawm nucleotide residues. Nyob rau hauv ib feeb, txuas ntxiv dua 1,000 nucleotide residues. Lub nucleotide residues nyob rau hauv ib tug qauv ntawm deoxyribonucleic acid fragment sib thooj, 3 ', 5'-phosphodiester bonds. DNA polymerase catalyzes qhov sib ntxiv ntawm mononucleotides residues rau cov dawb 3-hydroxyl kawg-hloov deoxyribonucleic acid. Thawj tsim me me ib feem ntawm cov DNA molecule. Lawv kam txais lawv tus kheej mus rau lub kev txiav txim ntawm DNA ligase tsim ib tug ntev tawg tsam ntawm deoxyribonucleic acid. Ob leeg thooj yog laus nyob rau hauv cell nuclei. Hloov deoxyribonucleic acid yog siv raws li tus taw tes ntawm kev loj hlob rau yav tom ntej DNA molecules thiab kuj yog ib tug matrix nyob rau hauv uas yog tsim nyob rau ib qho antiparallel Circuit Court deoxyribonucleic acid uas yog hloov nrog DNA yog zoo tib yam nyob rau hauv cov qauv thiab kev tso kawm ntawm tus nucleotide ib theem zuj zus ntawm residues. Replication ntawm DNA tshwm sim thaum lub sij hawm interphase mitotic cell division. Deoxyribonucleic acid yog feeb meej nyob rau hauv lub chromosomes thiab chromatin. Tom qab tsim ntawm single- deoxyribonucleic acid tsim nws theem nrab thiab tertiary lug. Ob tug strands ntawm deoxyribonucleic acid sib thooj, los ntawm hydrogen bonds ntawm complementarity txoj cai. DNA replication tshwm sim nyob rau hauv lub cell nuclei.

Duab txawv pawg rau lub biosynthesis ntawm cov RNA hom thiab lub zog-nplua nuj compound yog ATP, GTP, CTP thiab TTP. Ribonucleic acid tej zaum yuav tsim nyob rau ntawd muaj kev koom tes ntawm ib qho ntawm peb cov tawg tsam: lub DNA-dependent RNA polymerase, polynucleotide-nucleotidyltransferases thiab RNA-dependent RNA polymerase. Tus thawj ntawm no yog muaj nyob rau hauv lub nuclei ntawm tag nrho cov hlwb qhib kuj nyob rau hauv lub mitochondria. RNA tau tsim rau ib tug DNA template nyob rau hauv lub xub ntiag ntawm ribonucleoside triphosphates, Mangan thiab Magnesium ions. Ua RNA molecule complementary rau DNA template. Yuav kom DNA replication tshwm sim nyob rau hauv nuclei yog tsim p-RNA, t-RNA thiab RNA-RNA thiab priming. Thawj peb yog thauj mus rau lub cytoplasm, qhov uas lawv yuav muab kev koom tes nyob rau hauv protein biosynthesis.

DNA replication tshwm sim yuav luag zoo li raws li txhais los ntawm deoxyribonucleic acid. Kis raws li zoo raws li lub preservation ntawm kev tshuaj ntsuam genetic ntaub ntawv yog nqa tawm nyob rau hauv ob kauj ruam: transcription thiab txhais lus. Yuav ua li cas yog ib tug noob? Noob - ib cov khoom unit, uas yog ib feem ntawm lub lwg me me ntawm deoxyribonucleic acid (RNA nyob rau hauv ib co kab mob). Muaj nyob rau hauv lub chromosomes ntawm cell nuclei. Caj ntaub ntawv yog kis tau los ntawm DNA ntawm RNA rau protein. Transcription yog nqa tawm nyob rau hauv lub cell nucleus thiab belongs rau lub synthesis ntawm mRNA rau seem ntawm deoxyribonucleic acid molecules. Nws yuav tsum tau hais tias ib theem zuj zus ntawm deoxyribonucleic acid nucleotides "sau dua tshiab" nyob rau hauv lub nucleotide ib theem zuj zus ntawm lub molecule thiab RNA. RNA polymerase yog txuas mus rau lub sib nug xov DNA feem, "unwinds" nws muab ob npaug rau helix qauv thiab luam deoxyribonucleic acid nucleotides rau attaching lub hauv paus ntsiab lus ntawm complementarity. Raws li cov xaav fragment tsim RNA strand tsiv deb ntawm lub matrix, thiab ob-tso tseg DNA qab enzyme tam sim ntawd rov qab los. Yog hais tias lub RNA polymerase nce mus txog rau qhov kawg thiab theej feem tsiv deb ntawm lub RNA template nyob rau hauv karyoplasm ces txav mus rau hauv lub cytoplasm, qhov twg nws yuav siv sij hawm yog ib feem nyob rau hauv protein biosynthesis.

Thaum lub sij hawm tshaj tawm hauv xov qhov kev tso kawm nucleotide ib theem zuj zus nyob rau hauv lub molecule thiab RNA translates rau hauv ib tug sib lawv liag ntawm amino acid residues nyob rau hauv ib tug protein molecule. Qhov no txoj kev tshwm sim nyob rau hauv lub cytoplasm thiab RNA ua ke thiab tsim polysomes.