Lactose intolerance yog kev tsis txaus hauv lub peev xwm zom cov lactose, thiab yog vim muaj tus txheeb ze tsis muaj lactase enzyme hauv cov hnyuv.
YPuas yog lactase tshwj xeeb rau lactose?
Lactase pom muaj ntau tshaj plaws hauv villus enterocytes ntawm jejunum (thaum pib ntawm txoj hnyuv), thiab nws tshwj xeeb tsuas yog hydrolyzes noj lactose rau hauv qabzibthiab galactose rau kev thauj mus los. hla lub cell membrane.
YYuav ua li cas rau lactose thaum muaj lactase?
Ib txwm, thaum peb noj ib yam dab tsi uas muaj lactose, ib qho enzyme hauv cov hnyuv hu ua lactase rhuav nws mus rau hauv cov suab thaj yooj yim hu ua piam thaj thiab galactose. Cov suab thaj yooj yim no ces nqus mus rau hauv cov hlab ntsha thiab hloov mus ua zog.
YPuas yog lactase persistence dominant?
Lactase persistence yog an autosomal-dominant trait uas muaj ntau nyob rau hauv cov neeg European. Ib qho kev nyiam rau lactase persistence nce los ntawm sab qab teb sab hnub tuaj mus rau sab qaum teb sab hnub poob thoob plaws cov neeg nyob sab Europe tau raug sau tseg, tab sis cov xwm txheej zoo li no hauv lub tebchaws tsis tau kawm ntau.
Lactase persistence piv txwv ntawm yog dab tsi?
Lactase persistence yog ib phau ntawv piv txwv ntawm natural selection nyob rau hauv tib neeg: nws tau raug tshaj tawm los nthuav qhia kev xaiv muaj zog dua li lwm cov noob neeg paub. Txawm li cas los xij, tshwj xeeb yog vim li casYog vim li cas lactase persistence confers ib tug xaiv kom zoo dua "tseem qhib rau speculation".
