2024 Tus sau: Elizabeth Oswald | [email protected]. Kawg hloov kho: 2024-01-13 00:07
Thaum lub sijhawm meiosis I, homologous chromosomes ntawm txhua khub tuaj ua ke thiab ua ib sab ntawm ib sab hauv qhov xwm txheej hu ua synapsis. Synapsis tshwm sim hauv tetrad, ib qho kev koom ua ke ntawm plaub chromatids(ob homologous chromosomes uas muaj ob chromatids txhua).
Thaum nyob rau hauv meiosis kuv ua homologous chromosomes los ua ib tug tetrad?
In prophase I ntawm meiosis, cov chromosomes homologous tsim cov tetrads. Hauv metaphase I, cov khub no nyob rau ntawm qhov chaw nruab nrab ntawm ob tus ncej ntawm tes los tsim cov phaj metaphase.
tetrad hauv meiosis 1 yog dab tsi?
In meiosis. Txhua khub ntawm chromosomes-hu ua tetrad, los yog bivalent- muaj plaub chromatids. Lub sijhawm no, homologous chromosomes pauv cov khoom siv caj ces los ntawm cov txheej txheem hla (saib pawg sib txuas).
Dab tsi tshwm sim li homologous chromosomes khub thaum lub sijhawm prophase 1 ntawm meiosis?
Lub sijhawm prophase I, homologous chromosomes khub thiab tsim synapses, ib kauj ruam tshwj xeeb rau meiosis. Cov chromosomes ua ke yog hu ua bivalents, thiab tsim ntawm chiasmata tshwm sim los ntawm caj ces recombination ua pom tseeb. Chromosomal condensation tso cai rau cov no los saib hauv lub tshuab tsom.
Yuav ua li cas rau homologous chromosomes thaum lub sij hawm meiosis?
Thaum recombination tshwm sim thaum lub sij hawm meiosis, cell's homologous chromosomes kab ntau heev.nyob ze ib leeg. Tom qab ntawd, DNA strand nyob rau hauv txhua chromosome so nyob rau hauv tib qhov chaw, tawm hauv ob lub dawb xaus. Txhua qhov kawg ces hla mus rau lwm qhov chromosome thiab tsim kev sib txuas hu ua chiasma.
Pom zoo:
Lub sijhawm prophase ib khub homologous ntawm chromosomes muaj?
Cov lus teb raug: Cov chromosomes homologous muaj ob chromosomes thiab plaub chromatids nyob rau theem prophase. Yuav ua li cas rau chromosomes thaum lub sij hawm prophase? Thaum lub sijhawm prophase, qhov nyuaj ntawm DNA thiab cov proteins uas muaj nyob hauv cov nucleus, hu ua chromatin, condenses.
Lub sijhawm meiosis homologous khub ntawm chromosomes?
Ua ntej cov kab mob nkag mus rau meiosis, lawv feem ntau yog diploid, txhais tau tias lawv muaj ob daim ntawv luam ntawm txhua tus chromosome. Tom qab ntawd, ua ntej cov kab mob nkag mus rau hauv meiosis, nws duplicates nws DNA kom lub cell muaj plaub DNA luam tawm ntawm ob khub ntawm homologous chromosomes.
Lub sijhawm meiosis thaum twg kev sib tw ntawm chromosomes tshwm sim?
Thaum lub sijhawm prophase I, cov chromosomes condense thiab pom hauv lub nucleus. Vim tias txhua tus chromosome tau muab luam tawm thaum lub sijhawm the S theem uas tau tshwm sim ua ntej prophase I, txhua tus tam sim no muaj ob tus muam chromatids koom nrog ntawm centromere.
Puas yuav homologous chromosomes khub thaum meiosis?
Homologous chromosomes tsis ua haujlwm zoo ib yam hauv mitosis li lawv ua hauv meiosis. Ua ntej txhua tus mitotic faib ib lub xovtooj mus, cov chromosomes hauv niam txiv cell rov ua dua lawv tus kheej. Lub homologous chromosomes nyob rau hauv lub cell yuav ib txwm tsis ua khubthiab tau txais genetic recombination nrog ib leeg.
Thaum homologous chromosomes tsis cais?
1 NONDISJUNCTION Nondisjunction Nondisjunction Feem ntau ntawm cov teeb meem tshwm sim los ntawm kev tsis sib txuas thaum lub sij hawm niam txiv meiosis I. Trisomy tshwm sim nyob rau hauv tsawg kawg yog 0.3% ntawm cov menyuam mosthiab nyob rau hauv ze li ntawm 25% ntawm spontaneous rho menyuam.
