Qhov sib txawv tseem ceeb ntawm chiasmata thiab synaptonemal complex yog tias chiasmata yog cov qauv chromatin uas txuas homologous chromosomes rau cov ncej spindle, thaum cov synaptonemal complexes yog cov qauv protein uas kho synapsis thiab cross-over.
A chromosome yog ib yam khoom zoo li cov noob caj noob ces uas muaj cov noob muaj lub luag haujlwm rau cov yam ntxwv thiab cov yam ntxwv ntawm lub cev. Ib chromosome muaj ob txoj hlua zoo ib yam hu ua chromatids. Thaum lub sij hawm tus txheej txheem ntawm cell division, cov chromosomes replicate thiaj li hais tias lub resultant tus ntxhais cell tau txais tag nrho cov chromosomes. Homologous chromosomes txuas ua ke los ntawm cov qauv hu ua chiasmata. Thaum lub sij hawm kho kom haum xeeb ntawm kev sib koom ua ke ntawm homologous chromosomes, lub synaptonemal complex pib tsim.
Chiasmata yog dab tsi?
Chiasmata yog cov ntsiab lus ntawm kev sib cuag ntawm ob chromatids uas yog homologous chromosomes. Ntawm chiasma, kev sib pauv ntawm cov khoom siv caj ces tshwm sim ntawm ob chromatids, thiab nws yog hu ua chromosomal crossover. Cov xwm txheej zoo li no feem ntau tshwm sim hauv meiosis dua li hauv mitosis. Thaum lub tetrad sib cais, qhov chaw sib cuag uas tseem tshuav yog chiasmata. Nws tshwm sim thaum prophase I ntawm meiosis. Muam chromatids tsim chiasmata nruab nrab ntawm lawv, uas yog hu ua chi qauv. Txij li thaum lawv cov khoom siv caj ces zoo ib yam, lawv ua rau cov ntxhais zoo tib yam thiab tsis muaj qhov hloov pauv. Hauv cov tsiaj nyeg, tus naj npawb ntawm chromosomal caj npab sawv cev rau tus lej ntawm kev hla, thaum tib neeg, tsuas yog ib qho chiasma muaj nyob hauv chromosomal caj npab.
Daim duab 01: Meiosis Crossover
Chiasmata yog qhov tseem ceeb los txuas cov chromosomes homologous mus rau cov ncej ntxaiv, thiab kev sib cais yuav tshwm sim nrog cov ncej sib txawv thaum lub sij hawm meiosis I. Cov txheej txheem no hu ua bipolar txuas. Kev poob ntawm chiasmata ua rau tsis tsim nyog chromosomal cais thiab aneuploidy thaum anaphase. Lub ntsiab lus ntawm kev hla dhau los ua pom zoo li chiasma tom qab lub synaptonemal complex dissembles thiab homologous chromosomes sib cais los ntawm ib leeg.
Dab tsi yog Synaptonemal Complex?
Synaptonemal complex yog cov qauv protein uas tsim ntawm homologous chromosomes thaum lub sij hawm meiosis thiab mediates synapsis thiab recombination thaum meiosis I hauv eukaryotes. Synaptonemal complexes feem ntau ua raws li ib tug scaffold, tso cai rau kev sib cuam tshuam ntawm chromatids kom tiav cross-over. Ob sab qauv ntawm ob sab hu ua lateral ntsiab txuas los ntawm cov proteins hu ua transverse filaments.
Daim duab 02: Synaptonemal Complex
Synaptonemal complex tsim thaum lub sijhawm prophase hauv meiosis I. Cov ntaub ntawv synaptonemal complex tsim los ntawm kev sib koom ua ke ntawm homologous chromosomes thiab yog siv los soj ntsuam qhov muaj qhov txawv txav hauv kev ua khub. Lub synaptonemal complex qhia tsuas yog me ntsis kev hloov pauv hauv cov qauv txawm tias muaj cov protein sib txawv. Synaptonemal complex nqa recombination nodules uas koom nrog hauv nruab nrab qhov chaw. Cov nodules sib raug rau kev hla dhau los yog cov txheej xwm txheej txheem genetic recombination.
Dab tsi yog qhov zoo sib xws ntawm Chiasmata thiab Synaptonemal Complex?
- Chiasmata thiab synaptonemal complex pom hauv meiosis I.
- Ob lub qauv muaj rau homologous chromosomes.
- Ntxiv mus, lawv koom nrog hauv chromosomal crossover thaum lub sij hawm meiosis.
Qhov txawv ntawm Chiasmata thiab Synaptonemal Complex yog dab tsi?
Chiasmata yog cov qauv chromatin uas txuas cov chromosomes homologous rau cov ncej spindle, thaum synaptonemal complexes yog cov qauv protein uas kho synapsis thiab hla. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm chiasmata thiab synaptonemal complex. Tsis tas li ntawd, chiasmata yog cov qauv ntoo khaub lig, thaum lub synaptonemal complex zoo li cov qauv zipper. Ntxiv mus, chiasmata yog tsim los ntawm DNA thiab protein, thaum synaptonemal complex tsuas yog tsim los ntawm cov proteins.
Cov hauv qab no infographic nthuav tawm qhov sib txawv ntawm chiasmata thiab synaptonemal complex hauv daim ntawv tabular rau ib sab ntawm kev sib piv.
Summary – Chiasmata vs Synaptonemal Complex
Chiasmata yog cov ntsiab lus ntawm kev sib cuag ntawm ob chromatids uas yog homologous chromosomes. Synaptonemal complex yog cov qauv protein uas tsim ntawm homologous chromosomes thaum lub sij hawm meiosis, mediates synapsis, thiab recombination / cross-over. Chiasmata yog qhov tseem ceeb rau kev txuas cov chromosomes homologous mus rau cov ncej spindle, thiab kev sib cais yuav tshwm sim nrog cov ncej sib txawv thaum cov synaptonemal complexes ua raws li scaffold, tso cai rau kev sib cuam tshuam ntawm chromatids kom tiav hla. Yog li, qhov no qhia txog qhov sib txawv ntawm chiasmata thiab synaptonemal complex.
