Tus menyuam qhov muag xim dab tsi?

Tus menyuam qhov muag xim dab tsi?
Tus menyuam qhov muag xim dab tsi?
Anonim

Thaum tus me nyuam los rau hauv lub ntiaj teb no, niam tais yawm txiv, cov phooj ywg thiab cov neeg paub, cov phauj thiab txiv ntxawm thiab, cov niam txiv tshiab lawv tus kheej xav tsis thoob tias tus me nyuam zoo li cas. Leej twg lub qhov ntswg, qhov ncauj, puab tsaig. Thiab ib qho ntawm cov lus nug tseem ceeb yog: "Dab tsi qhov muag xim yuav tus menyuam muaj?" Cov niam txiv qhov muag xiav puas tuaj yeem muaj tus ntxhais xim av qhov muag? Los yog ob peb qhov muag tsaus nti - ib tug me nyuam tub nrog lub qhov muag xiav? Cia peb kawm!

Tus menyuam yuav muaj qhov muag xim dab tsi?
Tus menyuam yuav muaj qhov muag xim dab tsi?

Dab tsi txiav txim qhov muag xim hauv cov menyuam yaus? Tsis muaj peev xwm teb tsis tau qhov tseeb ntawm no, vim hais tias, txawm tias noob caj noob ces txiav txim siab 90% ntawm no, qhov seem 10% tseem nyob ntawm rooj plaub.

Cov xim ntawm tib neeg ob lub qhov muag yog txiav txim los ntawm tus nqi ntawm cov xim hu ua "melanin" hauv iris. Qhov tsawg kawg nkaus ntawm melanin txhais tau tias cov xim ntawm lub qhov muag yog xiav, qhov siab tshaj plaws yog xim av. Tus so ntawm cov xim thiab ntxoov yog nyob nruab nrab ntawm ob lub ntsiab lus ntawm lub spectrum. Tus nqi ntawm cov ximtxiav txim genetic.

Txhua tus menyuam mos yug tshiab muaj xim av tsaus lossis xiav-grey qhov muag. Tom qab ntawd, nyob ntawm qhov ceev thiab ntau npaum li cas ntawm melanin tsim los ntawm lub cev, cov xim ntawm lub qhov muag yuav hloov. Nws yog qhov ua tau thaum kawg txiav txim siab seb qhov muag xim twg tus menyuam yuav muaj thaum lawv mus txog peb xyoos. Txog rau thaum muaj hnub nyoog no, nws tuaj yeem hloov pauv, tab sis rau cov menyuam yaus feem ntau txhua yam yog qhov tseeb ntawm lub hnub nyoog ntawm rau lub hlis mus rau ib xyoos. Muaj kev zam rau txoj cai: muaj cov neeg uas nws qhov muag xim hloov mus thoob lub neej.

Nws yog ib qho yuam kev tias yog ob niam txiv lub qhov muag xim av, tus me nyuam yuav tsum muaj xim qhov muag tib yam. Ua rau lawv xav tsis thoob, tus me nyuam qhov muag xiav kuj tuaj yeem yug tau. Muaj pes tsawg tsev neeg tau tawg vim muaj cov xwm txheej zoo li no, thaum tib neeg tsis paub tias caj ces yog dab tsi. Tau kawg, kev ua xyem xyav poob rau ntawm tus poj niam. Lub caij no, txhua yam yog yooj yim heev. Cia peb saib cov piv txwv yooj yim tshaj plaws los ntawm phau ntawv kawm biology niaj hnub no.

tus menyuam lub qhov muag yuav xim dab tsi
tus menyuam lub qhov muag yuav xim dab tsi

tus menyuam qhov muag xim dab tsi? Koj tsis tuaj yeem kwv yees ua ntej. Txhua tus neeg muaj ob qhov sib txawv ntawm tib lub noob: niam thiab txiv. Ob versions ntawm ib tug noob hu ua alleles. Ib tug ntawm lawv yuav dominant, lwm tus - recessive. Yog li, xim av qhov muag xim yog qhov tseem ceeb. Tab sis tus me nyuam kuj tuaj yeem tau txais ib qho allele recessive los ntawm ib tug ntawm cov niam txiv.

Cia peb piav txog lub qhov muag xim av nrog tsab ntawv "K", thiab xim xiav, uas yog recessive, nrog me "g". Kev sib xyaw ntawm ob qho alleles, ib qho los ntawm txhua tus niam txiv, yog lub luag haujlwm rau qhov muag xim hauv tib neeg lub cev. Yog li, tus neeg qhov muag xim av yuav muaj qhov sib xyaw ua ke ntawm "KK" lossis "Kg". Tus me nyuam qhov muag xiav, dhau los, tsuas muaj "yy" xwb.

Ib tug me nyuam yuav muaj qhov muag xiav yog tias ob niam txiv qhov muag tsaus nti muaj xim av tsis tiav, uas yog, ob leeg muaj "Kg" allele. Yog hais tias ib tug me nyuam pog yawg muaj qhov muag xiav, lawv cov xeeb ntxwv tej zaum yuav xiav-eyed!

qhov muag xim nyob rau hauv cov me nyuam
qhov muag xim nyob rau hauv cov me nyuam

Mom "Kg" + dad "Kg"=KK (qhov muag xim av) lossis Kg (qhov muag daj) lossis gg (xiav-eyed).

Hnub no tseem muaj lub tshuab xam zauv tshwj xeeb rau kev txiav txim siab seb tus menyuam lub qhov muag yuav xim dab tsi. Tau kawg, peb cov lus piav qhia yog schematic heev thiab tsis muaj kev cuam tshuam tag nrho cov txheej txheem ntawm caj ces. Txawm li cas los xij, txoj kev xav thiab kev loj hlob ntawm tus me nyuam yog qhov paub tsis meej, thiab peb lub siab yeej tsis tuaj yeem paub nws. Lub qhov muag xim twg yuav tus menyuam muaj - nws puas tseem ceeb? Nws tseem ceeb dua kom nws noj qab haus huv thiab ua lub neej zoo siab, puas yog?

Pom zoo: