Cov theem ntawm mitosis: lawv cov yam ntxwv. Lub ntsiab lus ntawm mitotic cell division

Lub cell voj voog - lub sij hawm los ntawm ib tug cell division mus rau lub tom ntej no. Nws yuav siv sij hawm qhov chaw nyob rau hauv ob successive theem - interphase thiab cov division. Lub caij no cov txheej txheem raws nyob rau hauv lub hom hlwb.

Interphase yog ib lub sij hawm ntawm ob cell kev sib cais, lub sij hawm los ntawm lub xeem faib mus cell tuag los yog poob ntawm muaj peev xwm mus faib.

Nyob rau hauv lub sij hawm no, lub cell loj hlob thiab doubles nws DNA, raws li zoo raws li mitochondria thiab plastids. Nyob rau hauv interphase kis protein synthesis , thiab lwm yam organic tebchaw. Qhov tseem sib synthesis txheej txheem no yog muaj nyob rau hauv Synthesis interphase. Thaum lub sij hawm no, muab ob npaug rau nuclear chromatids, yog muab lub zog uas yuav siv tau thaum lub sij hawm lub division. Tsis tas li ntawd, ib tug zuj zus tooj ntawm tes organelles thiab centrioles.

Interphase occupies yuav luag 90% ntawm lub cell voj voog. Tom qab nws kis tau mitosis, uas yog lub ntsiab txoj kev sib cais ntawm eukaryotic hlwb (cov kab mob uas nws lub hlwb muaj ib tug nucleus tsim).

Thaum mitosis, lub chromosomes condensed thiab tsim ib tug tshwj xeeb apparatus, uas yog lub luag hauj lwm rau teeb tis ntawm kev tshuaj ntsuam genetic ntaub ntawv ntawm lub hlwb uas tsim los ntawm tus txheej txheem no.

Cell division yuav siv sij hawm qhov chaw nyob rau hauv ob peb ua sawv. mitotic theem yus muaj los ntawm ib tug neeg tus yam ntxwv thiab ib tug tej yam ntev.

Cov theem ntawm mitosis

Thaum hlwb yauv mitosis coj theem ntawm mitosis: prophase, metaphase tom qab nws mus, anaphase, telophase yog zaum kawg.

mitotic theem tsiag ntawv los ntawm cov nram qab no nta:

• prophase - ploj lub nuclear lub hnab ntawv. Nyob rau hauv no theem, cov centrioles diverge rau ncej ntawm lub cell thiab chromosomes condensed (compacted);
• metaphase - Siv yus maximally compacted chromosomes uas muaj li ntawm ob chromatids ntawm qhov ncaj (nruab nrab) ntawm tes. Qhov no tshwm sim yog hu ua tus metaphase phaj. Nws yog ua tau mus xyuas chromosomes nyob rau hauv ib tug tshuab kuaj kab mob zoo qhia. Nyob rau hauv metaphase ntawm mitosis tshwm sim kuj muab ib kawg ntawm ntxaiv threads rau centromeres ntawm chromosomes lwm kawg - mus rau lub centrioles.
• anaphase - qhia yog qhov kev sib cais ntawm cov chromosomes nyob rau hauv lub chromatids (lawv disperse rau txawv tug). Yog li chromatids ua cais chromosomes, uas muaj xws li tsuas yog ib chromatid xov;
• telophase - yus decondensation chromosomes thiab tsim nyob ib ncig ntawm txhua chromosome ntawm ib tug tshiab nuclear lub hnab ntawv. ntxaiv filament ploj nyob rau hauv lub nucleus tshwm nucleoli. Nyob rau hauv telophase thiab cytokinesis dhau mus, uas yog ib tug faib ntawm lub cytoplasm ntawm tus ntxhais lub hlwb. Qhov no txoj kev yog nqa tawm nyob rau hauv cov tsiaj vim lub tshwj xeeb cleavage furrow (duav, uas cais lub cell nyob rau hauv ob). Nyob rau hauv cog hlwb cytokinesis txheej txheem cell phaj muab lub Golgi complex.

Yuav ua li cas yog lom tseem ceeb ntawm mitosis txheej txheem?

Cov theem ntawm mitosis pab txhawb tseeb kis tau tus mob ntawm kev tshuaj ntsuam genetic ntaub ntawv mus rau tus ntxhais lub hlwb, tsis hais txog ntawm lub xov tooj ntawm kev sib cais. Yog li txhua yam uas lawv tau txais ib chromatid uas yuav pab tswj tau cov taub hau xov tooj ntawm chromosomes nyob rau hauv tag nrho cov hlwb uas tsim los mus faib. Nws muab kis tau tus mob ntawm mitosis sustainable set kev tshuaj ntsuam genetic khoom.