Barbara McClintock

**Barbara McClintock** (16 ga Yuni, 1902 - Satumba 2, 1992) masaniyar kimiyar Amurka ce kuma masaniyar cytogeneticist wadda aka ba ta lambar yabo ta Nobel ta 1983 a fannin ilimin halittar jiki ko magani. McClintock ta samu digirin digirgir a fannin ilmin halitta daga Jami'ar Cornell a shekarar 1927. A nan ne ta fara aikinta a matsayin jagorar bunkasar sinadarai na masara, abin da ya fi mayar da hankali kan bincikenta har karshen rayuwarta. Daga ƙarshen 1920s, McClintock yayi nazarin chromosomes da yadda suke canzawa yayin haifuwa a cikin masara. Ta ƙirƙiro dabarar hangen ƙwayoyin chromosomes na masara kuma ta yi amfani da bincike na ɗan ƙaramin abu don nuna mahimman ra'ayoyin kwayoyin halitta. Ɗaya daga cikin waɗannan ra'ayoyin shine ra'ayin sake hadewar kwayoyin halitta ta hanyar hayewa a lokacin meiosis - tsarin da chromosomes ke musayar bayanai. Ta samar da taswirar kwayar halitta ta farko don masara, ta haɗa yankuna na chromosome zuwa halaye na zahiri. Ta nuna rawar da telomere da centromere, yankuna na chromosome da ke da mahimmanci wajen kiyaye bayanan kwayoyin halitta. An gane ta a matsayin mafi kyau a fagen, an ba ta abokan hulɗa mai daraja, kuma ta zaɓi memba na Kwalejin Kimiyya ta Kasa a 1944.

## Rayuwar baya
Barbara McClintock an haife ta a Eleanor McClintock a watan Yuni 16, 1902, a Hartford, Connecticut, na uku cikin yara huɗu da aka haifa ga likitan homeopathic Thomas Henry McClintock da Sara Handy McClintock. Thomas McClintock ɗan baƙi ne na Burtaniya. Marjorie, ɗan fari, an haife shi a watan Oktoba 1898; Mignon, 'yar ta biyu, an haife ta a watan Nuwamba 1900. Karamin, Malcolm Rider (wanda ake kira Tom), an haife shi watanni 18 bayan Barbara. Lokacin da take ƙaramar yarinya, iyayenta sun yanke shawarar cewa Eleanor, sunan "mata" da "m" bai dace da ita ba, kuma suka zaɓi Barbara maimakon. McClintock yarinya ce mai cin gashin kanta tun tana ƙarama, yanayin da daga baya ta gano a matsayin "ikon zama ita kaɗai". Tun tana da shekaru uku har ta fara makaranta, McClintock ta zauna tare da kawu da kawu a Brooklyn, New York, don rage nauyin kuɗi a kan iyayenta yayin da mahaifinta ya kafa aikin likita. An bayyana ta a matsayin yarinya mai zaman kanta kuma mai zaman kanta. Ta kasance kusa da mahaifinta, amma tana da dangantaka mai wahala da mahaifiyarta, tashin hankali wanda ya fara tun tana karama.

## Ilimi da bincike a Cornell
McClintock ta fara karatunta a Kwalejin Aikin Noma na Cornell a 1919. A can, ta shiga cikin gwamnatin dalibai kuma an gayyace ta don shiga cikin shirin, ko da yake ba da daɗewa ba ta gane cewa ta fi son shiga ƙungiyoyi na yau da kullum. Maimakon haka, McClintock ya ɗauki kiɗa, musamman jazz. Ta yi karatun botany, inda ta sami digirin BSc a shekarar 1923. Sha'awarta game da ilimin halittu ta fara ne lokacin da ta fara karatun ta na farko a wannan fanni a cikin 1921. Kos ɗin ya dogara ne akan irin wanda aka bayar a Jami'ar Harvard, kuma C. B. Hutchison, masanin kiwo kuma masanin ilimin halittu ne ya koyar da shi. Sha'awar McClintock ta burge Hutchison, kuma ya buga waya ya gayyace ta don shiga cikin karatun digiri na biyu na ilimin halittar jini a Cornell a shekara ta 1922. McClintock ya nuna gayyatar Hutchison a matsayin abin da zai haifar mata da sha'awar kwayoyin halitta: "Babu shakka, wannan kiran tarho ya jefa mutuwa a nan gaba ta. Na kasance tare da kwayoyin halitta bayan haka." Cornell, sabili da haka MS da PhD - wanda aka samu a 1925 da 1927, bi da bi - an ba su kyauta a hukumance a fannin ilimin botany, bincike na baya-bayan nan ya nuna cewa an ba wa mata damar samun digiri na biyu a Sashen Kiwo na Cornell a lokacin da McClintock dalibi ne a Cornell.

## Manazarta