Yintoni egqibayo umbala wamehlo?

Njengoko abantwana ilifa umbala wamehlo? Ngaba kunokwenzeka ukuba baqashele ukuba iza kuba njani na umntwana? Kutheni na ukuba albino elipinki? Ukuba bobabini abazali kunye abrawuni, ukuba azalwe ngoko ukuba, nelebhokhwe blue-eyed? Njani na umbala iris? Le mibuzo ehambisana ngawo onke amaxesha. Impendulo kuzo eziqulathwe iimpawu zizonke zangaphakathi nangaphandle ze umzimba kwakheka kwi isiseko kweejini kwakunye abazifumene kuphuhliso ngamnye. Kuthetha ntoni oku, yaye yintoni kugqiba umbala iliso ebantwini?

Olu phawu ke emiselwe nombala iris (iris) equlathe ectodermal (adjustable) kunye mesodermal (ngaphambili) zikhabane. Oko kukuthi, umbala Iliso lomntu kuxhomekeke kuhlobo fustsina lonikezelo (inceda ukuvelisa ebala ezibonwayo ibizela ukukhanya kwaye uthintele ukuzibhubhisa yayo kunye reflection, oko kukhokelele ukuphuculwa ndikho yomfanekiso olubonakalayo) kwizisele sombala backsheet kunye bala lintsundu (esimnyama zendalo) kwi kombala-equlethe kwaye ukukhanya-ebonakalisa iiseli (chromatophores) esibekwa ngaphambili. Kwi umbala kwakhona alichatshazelwa urhulumente iimpahla samehlo neerhali, inani ezahlukeneyo nohlobo kombala, nto leyo eqinisekisa Genet. Iliso umbala ibangwa yemfuza. Kodwa asingabo bonke abayiqondayo.

Bala lintsundu akuphela kwento anemibala, oko kuchaphazela kuphela umbala yamehlo, kodwa iinwele kunye nesikhumba neethowuni. Kodwa, yintoni limisa umbala amehlo? Melanin ngaphezulu eziqulathwe kule nwebu mesodermal, lo mnyama iris, yaye ezincinane oko isasazwa iiseli mbala lo maleko Icipande iris, lighter na. Kukho bala lintsundu brown and black (okanye eumelanin), kunye esimthubi (okanye pheomelanin). Kuba uhlobo kunye nobungakanani weli zendalo kunye nokuhanjiswa yayo ekwafanekisa yemfuza ezithile. Ngenxa yoko, kombala iris ukuze blue, oluhlaza, ongwevu, eluhlaza, evuthiweyo, Marsh, Carey nokuba lube mnyama. Umntwana uya kulidla ilifa ukufana kunye nomzali nokuba iimpawu lubalaseleyo (brown, ukukhanya brown and green) yaye akazange ukufumana umbala amehlo umzali kunye imikhwa sofuzo (blue okanye grey).

Xa amehlo aluhlaza maleko umva elinombala oluhlaza ngenxa kwimicu collagen semithambo kuyilwa, umaleko ngaphambili uba isiqulatho ubuncinane-bala lintsundu. Blue kwahluka loxinano ezimhlophe blue ephezulu kwimicu: eliphezulu lexinene, lighter iris. Gray iliso umbala kungenxa ezixineneyo ngakumbi collagen. Umaleko phambi imali encinane-bala lintsundu eluhlaza ngenxa blue imibala umaleko iris adjustable yi inhomogeneously mibala eziluhlaza ezahlukeneyo. Yintoni limisa umbala amehlo yegolide evuthiweyo? Le lipofuscin sombala iqinisekisa umbala wawo efanayo. Nokulolonga isiqulatho bala lintsundu ukuba inwebu zangaphandle iliso abe kumgxobhozo okanye Anut. Brown xa chromatophores ziqulethe eninzi-bala lintsundu. Kuba emnyama ebonakala ezinomthamo eliphezulu sakhi, nto leyo ethintela ngokupheleleyo ukukhanya. Xa albino yena engekho, kwaye iris ibonakala pink okanye obomvu ngenxa vangama umbala kwemithambo yegazi.

Kubelekwa babe samehlo emsi, kodwa kusenokuba mnyama kule minyaka imbalwa izayo. Kutheni le nto noko limisa umbala amehlo womntwana? zange ziphuhliswe I-bala lintsundu emzimbeni ngexesha kokuzalwa kosana olungekazalwa ke, ekubeni kungekho nto kude kube lelo xesha, ukhuseleko UV, oluqhutywa kudala emnyama. injongo yawo - ukuba ukuthintela umonakalo radiation ukuya kwinyama zomzimba. Emva kokubeleka, uqala imveliso-bala lintsundu ngokuthi iiseli ezizodwa (melanocytes). Ngoko ke, lo umbala yokwenene iliso yomntwana zingenakuqinisekiswa ngaphambili ngaphezu kweminyaka emithathu, nangona utshintsho ngamanye amaxesha ukuya kwiminyaka 10-12. Abadala kwakhona ukutshintsha umbala iris phantsi kwempembelelo yeziyobisi okanye ngenxa yempilo enkenenkene. Umzekelo, kukho kombala bulubhelu ngenxa beqokelela lipofuscin.

Ngokuqhelekileyo zithathwa ukuba amehlo lubalaseleyo elimdaka, nemnyama oluhlaza - sofuzo. Kodwa inzululwazi yanamhlanje iye kubonakele ukuba akukho ilula kakhulu. I-mnyama umbala, kokukhona bulawulwe: Brown ku eluhlaza, eluhlaza okwesibhakabhaka. Kodwa ayisoloko kuba umntwana brown wayemangalisiwe, ukuba iris ukusuka nomama notata brown. Xa abantwana, kunokuba ezahlukeneyo. Ngokuqhelekileyo oku kubangwa luphuhliso yayiphosakele zothutho sakhi, umothuko wasekuhlaleni, okanye esizalweni okanye kamsinya emva kokuzalwa, kwakunye nesifo yemfuza.