Cov txheej txheem:
- Kev tsis sib haum xeeb yog dab tsi thiab nws tshwm sim thaum twg?
- Dab tsi ua rau chromosome nondisjunction?
- Vim li cas Nondisjunction tshwm sim hauv chromosome 21?
- Tsis muaj kev cuam tshuam tshwm sim nyob qhov twg hauv lub voj voog ntawm tes?
Video: Thaum twg tsis muaj kev cuam tshuam ntawm chromosomes tshwm sim?
2024 Tus sau: Fiona Howard | [email protected]. Kawg hloov kho: 2024-01-10 06:38
Nondisjunction tuaj yeem tshwm sim thaum anaphase of mitosis, meiosis I, lossis meiosis II. Thaum lub sij hawm anaphase, tus muam chromatids (los yog homologous chromosomes rau meiosis I), yuav sib cais thiab txav mus rau cov ncej ntawm tes, rub los ntawm microtubules.
Kev tsis sib haum xeeb yog dab tsi thiab nws tshwm sim thaum twg?
1 NONDISJUNCTION
Nondisjunction txhais tau hais tias ib khub ntawm homologous chromosomes tsis tau cais lossis cais ntawm anaphase kom ob leeg chromosomes ntawm khub dhau mus rau tib tus ntxhais cellQhov no feem ntau tshwm sim hauv meiosis, tab sis nws yuav tshwm sim hauv mitosis los tsim ib tus neeg mosaic.
Dab tsi ua rau chromosome nondisjunction?
Nondisjunction tshwm sim thaum homologous chromosomes (meiosis I) los yog tus muam chromatids (meiosis II) tsis cais thaum lub sij hawm meiosis Tus neeg uas muaj cov chromosomes tsim nyog rau lawv hom hu ua euploid; Hauv tib neeg, euploidy sib raug rau 22 khub ntawm autosomes thiab ib khub ntawm kev sib deev chromosomes.
Vim li cas Nondisjunction tshwm sim hauv chromosome 21?
Cov yam ntxwv ntawm chromosome 21 nondisjunction yog ib qho ntawm ntau yam ntawm tib neeg autosomes. Ntawd yog, feem ntau dhau los yog vim qhov ua yuam kev thaum lub sijhawm oogenesis: tsawg kawg 90% ntawm cov neeg mob chromosome 21 nondisjunction yog vim leej niam meiotic yuam kev [1], [2].
Tsis muaj kev cuam tshuam tshwm sim nyob qhov twg hauv lub voj voog ntawm tes?
Nondisjunction, uas chromosomes tsis sib luag, tuaj yeem tshwm sim hauv meiosis I (ib kab), meiosis II (kab ob), thiab mitosis (kab peb). Cov kev sib cais tsis sib xws no tuaj yeem tsim cov menyuam ntxhais nrog tus lej chromosome uas tsis tau xav txog, hu ua aneuploids.
Pom zoo:
Thaum twg muaj kev cuam tshuam tshwm sim?
Kev poob siab yog tshwm sim los ntawm ntau dhau vasodilation thiab tsis txaus faib cov ntshav txaus(piv txwv li, ncaj qha arteriovenous shunting), thiab nws yog tus yam ntxwv los ntawm kev txo qis lossis nce venous muaj peev xwm los ntawm vasomotor kev ua haujlwm tsis zoo .
Cuam tshuam lossis cuam tshuam li cas cuam tshuam kev sib txuas lus?
Txhua zaus peb tham lossis mloog, muaj tej yam uas nkag mus rau hauv txoj kev sib txuas lus meej-yam uas cuam tshuam rau tus neeg txais tau cov lus los ntawm tus xa. Qhov kev cuam tshuam no yog hu ua " noise," thiab muaj ntau hom suab nrov uas tuaj yeem ua rau cov lus raug txhais tsis raug .
Lub sijhawm meiosis tsis muaj kev cuam tshuam tuaj yeem tshwm sim hauv?
Nondisjunction tuaj yeem tshwm sim thaum anaphase of mitosis, meiosis I, lossis meiosis II. Thaum lub sij hawm anaphase, tus muam chromatids (los yog homologous chromosomes rau meiosis I), yuav sib cais thiab txav mus rau cov ncej ntawm tes, rub los ntawm microtubules .
Nyob rau hauv ib qho kev tsis sib haum xeeb pn kev sib tshuam cov kev sib tshuam tam sim no ntawm qhov sib npaug yog?
Nyob rau hauv qhov tsis ncaj ncees PN-kho qhov kev sib tshuam tam sim no ntawm qhov sib npaug yog zero, vim tias sib npaug tab sis cov neeg nqa khoom hla hla kev sib tshuam . Thaum pn kev sib tshuam tsis ncaj ncees qhov kev sib tshuam tam sim no ntawm qhov sib npaug yog?
Qhov twg hauv qab no yog piv txwv ntawm kev cuam tshuam kev cuam tshuam?
Piv txwv ntawm kev cuam tshuam muaj xws li roob, hav zoov, suab puam, nroog thiab lub cev dej. Qee qhov kev thaiv no thaiv kev tsiv teb tsaws ntawm qee hom, thaum lawv tsis ua kom qeeb lwm hom tsiaj . piv txwv ntawm kev cuam tshuam kev cuam tshuam yog dab tsi?
