2024 Tus sau: Elizabeth Oswald | [email protected]. Kawg hloov kho: 2024-01-13 00:07
Raws li kev sib deev chromosomes, ob X chromosomes raug suav tias yog homologous whereas X thiab Y chromosomes tsis yog. Yog li, poj niam muaj 23 homologous chromosomes (piv txwv li 22 autosomes + 1 X-X chromosomes) hos txiv neej tsuas muaj 22.
Puas XY chromosomes dominant?
Cov qauv ntawm X thiab Y chromosomes
Vim tias cov noob ntxiv hauv X chromosome tsis muaj qhov sib piv hauv Y chromosome, cov noob X yog qhov tseem ceeb. Qhov no txhais tau hais tias yuav luag txhua cov noob ntawm X, txawm tias nws yog tus poj niam recessive, yuav qhia rau txiv neej.
Puas yog txiv neej chromosomes homologous?
Yog li raws li thawj ob lub ntsiab lus, kwv yees li ib nrab ntawm tib neeg muaj 23 homologous ntawm chromosomes (poj niam, XX), hos lwm ib nrab muaj 22 homologous khub, nrog 23rd khub tsis yog. -homologous (txiv neej, XY).
Dab tsi yog homologous khub ntawm chromosomes?
Ob lub chromosomes hauv ib khub homologous yog zoo ib yam thiab muaj qhov loj thiab zoo tib yam. Qhov tseem ceeb tshaj plaws, lawv nqa tib yam ntaub ntawv ntawm caj ces: uas yog, lawv muaj tib lub noob nyob rau hauv tib qhov chaw. Txawm li cas los xij, lawv tsis tas yuav muaj tib cov qauv ntawm cov noob.
Dab tsi yog qhov txawv ntawm Chromatin thiab chromosomes?
Chromatin yog ib qho nyuaj tsim los ntawm histones ntim cov DNA ob chav helix. Chromosomes yog cov qauv ntawm cov protein thiab nucleic acids pom nyob rau hauvcov hlwb muaj sia thiab nqa cov khoom siv caj ces. Chromatin yog tsim los ntawm nucleosomes. Chromosomes yog tsim los ntawm condensed chromatin fibers.
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.
Yuav tsum ua kom homologous chromosomes khub?
Lub homologous chromosomes nyob rau hauv lub cell yuav tsis ua khubthiab tau txais kev tshuaj ntsuam genetic recombination nrog ib leeg. Vim li cas homologous chromosomes khub? Lub homologous chromosomes nyob rau hauv lub nucleus ntawm lub cev gamete khub thaum lub sij hawm meiosis.
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.
Thaum meiosis kuv cov homologous chromosomes ntawm tetrad?
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).
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.
