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.
