1950 y\u0131l\u0131ndan itibaren DNA yap\u0131s\u0131n\u0131n k\u0131sa s\u00fcre i\u00e7inde \u00e7\u00f6z\u00fclece\u011fi kuvvetle tahmin ediliyordu.Bilimle u\u011fra\u015fanlara g\u00f6re bu i\u015fi ba\u015faracak ki\u015fi Linus Pauling\u2019ten ba\u015fkas\u0131 olamazd\u0131.Zira Pauling, molek\u00fcllerin birbirleriyle ili\u015fkisi ve dizili\u015fleri konusunda d\u00fcnya \u00e7ap\u0131nda uzmand\u0131.Ancak \u00fcn\u00fcne \u00fcn katmas\u0131n\u0131 \u00f6nleyen \u015fey,bilimsel y\u00f6nden sabit fikirlili\u011fi oldu.DNA yap\u0131s\u0131n\u0131n \u00fc\u00e7l\u00fc sarmal \u015feklinde oldu\u011funu kabul etmi\u015fti ve bu noktada yo\u011funla\u015fm\u0131\u015ft\u0131.<\/p>\n
Asl\u0131nda DNA\u2019n\u0131n bilim literat\u00fcr\u00fcne giri\u015fi 1869 y\u0131l\u0131nda ba\u015flar.\u0130svi\u00e7re\u2019li J.F.Miescher,mikroskopla yapt\u0131\u011f\u0131 g\u00f6zlemlerde,\u00f6nceden bilmedi\u011fi bir madde g\u00f6rm\u00fc\u015ft\u00fc.Bu madde h\u00fccrenin \u00e7ekirde\u011finde oldu\u011fu i\u00e7in ona n\u00fcklein ad\u0131n\u0131 verdi,ama daha \u00f6teye gidemedi.Sonralar\u0131 bu maddenin kal\u0131t\u0131mla olan ilgisi kabul edildi,ama tam anlam\u0131yla fonksiyonu anla\u015f\u0131lmad\u0131.1900\u2019l\u00fc y\u0131llar\u0131n ba\u015f\u0131nda Morgan,me\u015fhur sirkesine\u011fi deneyleri ile genlerin kal\u0131t\u0131mdaki rol\u00fcn\u00fc anlad\u0131.Daha sonra O.Avery, DNA\u2019n\u0131n kal\u0131t\u0131m olay\u0131nda birinci derede rol oynad\u0131\u011f\u0131n\u0131 kesinlikle kan\u0131tlad\u0131.Ancak yap\u0131s\u0131n\u0131n ne \u015fekilde oldu\u011fu 1953 y\u0131l\u0131na kadar bilinemeyecekti.<\/p>\n
Maurice Wilkins,sava\u015f s\u0131ras\u0131nda atom bombas\u0131n\u0131n tasarlanma a\u015famas\u0131nda yard\u0131mc\u0131 olarak g\u00f6rev alm\u0131\u015ft\u0131.Rosalind Franklin, k\u00f6m\u00fcr madenlerini inceleyerek h\u00fck\u00fcmete yard\u0131m eden bayan bilimci idi.Francis Crick,sava\u015f y\u0131llar\u0131n\u0131 m\u0131knat\u0131sl\u0131 may\u0131nlar konusundaki \u00e7al\u0131\u015fmalar\u0131 ile tamamlad\u0131.
\nBiyokimya dal\u0131nda resmi \u00f6\u011frenim g\u00f6rmemi\u015fti.James Watson ise doktoras\u0131n\u0131 daha 22 ya\u015f\u0131nda iken alm\u0131\u015f bir ki\u015fiydi.Bir y\u0131l sonra,yani 1951 \u2018de Cavendish Laboratuvar\u0131\u2019nda i\u015fe ba\u015flad\u0131.Onun da biyokimya ile ilgili resmi \u00f6\u011frenimi yoktu.
\n*
\nBir DNA molek\u00fcl\u00fc yapt\u0131\u011f\u0131 i\u015fleri nas\u0131l yapar?Bu sorunun cevab\u0131n\u0131 bulmak i\u00e7in gereken ilk \u015fey,onun \u015feklini belirlemektir.Cevab\u0131n\u0131 arad\u0131klar\u0131 konu hem kimya hem de biyoloji ile do\u011frudan do\u011fruya ili\u015fkili idi.Watson,kimyay\u0131 kapsaml\u0131 olarak bilmiyordu ama kristalografi ihtisas\u0131 yapmaktayd\u0131.
\nCrick ise o s\u0131ralar X-\u0131\u015f\u0131n\u0131m\u0131 konusunu alm\u0131\u015f,tezini yazmakla me\u015fguld\u00fc.Wilkins ve bayan Franklin bu proje \u00fczerine \u00e7al\u0131\u015fmakta idiler.Her ikisi de Watson ve Crick\u2019in rakibi konumundayd\u0131lar.<\/p>\n
Kristalografi,atom ve molek\u00fclleri \u00fc\u00e7 boyutlu haliyle dizili\u015flerini inceler.X-\u0131\u015f\u0131n\u0131 kullan\u0131larak yap\u0131lan bu tekni\u011fi Pauling geli\u015ftirmi\u015fti.Ancak DNA yap\u0131s\u0131n\u0131 ortaya \u00e7\u0131karacak g\u00f6r\u00fcnt\u00fcleri bu teknikle elde eden ki\u015fi bayan Franklin oldu.\u00dcstelik ba\u015fard\u0131\u011f\u0131 i\u015f,mineral kristallerindeki atomlar\u0131n dizili\u015fini g\u00f6r\u00fcnt\u00fclemekten daha zordu.Ama elde etti\u011fi sonu\u00e7lar\u0131 kimseye a\u00e7\u0131klam\u0131yor,kendine sakl\u0131yordu.<\/p>\n
Wilkins ,bayan Franklin\u2019in bu tutumundan olduk\u00e7a rahats\u0131zd\u0131.Onun bu ketumlu\u011funu \u00e7al\u0131\u015fmalar\u0131ndaki ortakl\u0131k ili\u015fkisi ile ba\u011fda\u015ft\u0131ram\u0131yordu.
\nDi\u011fer taraftan Watson ve Crick \u00e7al\u0131\u015fmalar\u0131nda daha uyumlu idiler.Ama onlar\u0131n da bayan Franklin\u2019in bulgular\u0131na ihtiya\u00e7lar\u0131 vard\u0131,bu y\u00fczden ona bir nevi bask\u0131 yap\u0131yorlard\u0131.Gelgelelim bayan Franklin\u2019in bildiklerini payla\u015fmaya niyeti yoktu,\u00fcstelik DNA\u2019n\u0131n sarmal oldu\u011funa inanm\u0131yordu.1950\u2019li y\u0131llarda \u0130ngiltere\u2019de kad\u0131n akademisyenler hala gelenekle\u015fmi\u015f \u015fekilde hor g\u00f6r\u00fcl\u00fcrlerdi.Erkek akademisyenlerin odalar\u0131na giremezler,yemeklerini bile ayr\u0131 yerlerde yerlerdi.Belki de bayan Franklin yirminci y\u00fczy\u0131l\u0131n ikinci yar\u0131s\u0131nda bile terk edilmeyen bu gelene\u011fi protesto ediyordu.<\/p>\n
Ama sonralar\u0131 durum de\u011fi\u015fti.1953 y\u0131l\u0131n\u0131n ocak ay\u0131nda Wilkins DNA g\u00f6r\u00fcnt\u00fclerini bayan Franklin\u2019den alabildi.Ve bu g\u00f6r\u00fcnt\u00fcleri Watson\u2019a g\u00f6sterdi.Tabii o da bu bilgileri hemen Crick ile payla\u015ft\u0131.Wilkins\u2019in DNA g\u00f6r\u00fcnt\u00fclerini bayan Franklin\u2019in r\u0131zas\u0131n\u0131 alarak m\u0131 Watson\u2019a g\u00f6sterdi\u011fi \u015f\u00fcpheli kalm\u0131\u015ft\u0131r.Art\u0131k Watson ile Crick\u2019in DNA molek\u00fcl\u00fcn\u00fcn temel bi\u00e7imine ve boyutlar\u0131na ait \u00f6nemli klavuzu olmu\u015ftu.\u00c7al\u0131\u015fmalar\u0131n\u0131 yo\u011fun bir tempo ile s\u00fcrd\u00fcrmeye ba\u015flad\u0131lar.DNA\u2019n\u0131n adenin,guanin,sitozin ve timin olarak adland\u0131r\u0131lan 4 tane kimyasal bile\u015feni oldu\u011fu zaten biliniyordu.
\nBunlar da belirli \u00e7iftler halinde bir aradayd\u0131lar.Ama nas\u0131l ve ne \u015fekilde idiler?
\n*
\nWatson ile Crick molek\u00fcl \u015fekillerine g\u00f6re kartonlar kestiler.T\u0131pk\u0131 yapboz oyununda oldu\u011fu gibi bu karton par\u00e7alar\u0131n\u0131n hangisinin hangisine uygun oldu\u011funu ara\u015ft\u0131rd\u0131lar.Deneye deneye DNA\u2019n\u0131n sarmal olu\u015fturacak \u015fekilde modelini yapt\u0131lar.Ba\u015flang\u0131\u00e7tan o g\u00fcne dek DNA hakk\u0131nda bilinen her\u015fey yapt\u0131klar\u0131 bu modele t\u0131pat\u0131p uygulanabiliyordu.Bu ba\u015far\u0131lar\u0131n\u0131 b\u00fct\u00fcn d\u00fcnyaya ilan ettiler.
\n*
\nDNA\u2019ya ait bilinmeyen \u00f6zelliklerin ortaya \u00e7\u0131kar\u0131l\u0131\u015f\u0131 t\u00fcm\u00fcyle Watson ile Crick\u2019e mal edilmi\u015fti.Asl\u0131nda yapt\u0131klar\u0131 bulu\u015f,rakipleri taraf\u0131ndan yap\u0131lan \u00e7al\u0131\u015fmalar sayesinde olmu\u015ftu.Bilim d\u00fcnyas\u0131nda b\u00f6yle olaylar s\u0131k s\u0131k g\u00f6r\u00fcl\u00fcr,ba\u015far\u0131 \u00f6d\u00fcl\u00fc t\u00fcm\u00fcyle bir veya iki ki\u015fiye verilir.Ancak Nobel \u00d6d\u00fcl\u00fc\u2019n\u00fc d\u00fczenleyen yetkililer Wilkins\u2019i ihmal etmediler.1962 y\u0131l\u0131 Nobel T\u0131p \u00d6d\u00fcl\u00fc Watson, Crick ve Wilkins aras\u0131nda payla\u015ft\u0131r\u0131ld\u0131.Bayan Franklin ortak edilmedi.1958 y\u0131l\u0131nda \u00f6lm\u00fc\u015ft\u00fc.<\/p>\n","protected":false},"excerpt":{"rendered":"
1950 y\u0131l\u0131ndan itibaren DNA yap\u0131s\u0131n\u0131n k\u0131sa s\u00fcre i\u00e7inde \u00e7\u00f6z\u00fclece\u011fi kuvvetle tahmin ediliyordu.Bilimle u\u011fra\u015fanlara g\u00f6re bu i\u015fi ba\u015faracak ki\u015fi Linus Pauling\u2019ten ba\u015fkas\u0131 olamazd\u0131.Zira Pauling, molek\u00fcllerin birbirleriyle ili\u015fkisi ve dizili\u015fleri konusunda d\u00fcnya \u00e7ap\u0131nda uzmand\u0131.Ancak \u00fcn\u00fcne \u00fcn katmas\u0131n\u0131 \u00f6nleyen \u015fey,bilimsel y\u00f6nden sabit fikirlili\u011fi oldu.DNA yap\u0131s\u0131n\u0131n \u00fc\u00e7l\u00fc sarmal \u015feklinde oldu\u011funu kabul etmi\u015fti ve bu noktada yo\u011funla\u015fm\u0131\u015ft\u0131. Asl\u0131nda DNA\u2019n\u0131n bilim …<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1407,1403],"tags":[6082,6081,6084,6085,6083],"class_list":["post-2404","post","type-post","status-publish","format-standard","hentry","category-fen-ve-teknoloji-odevleri","category-odevler","tag-atom-bombasi","tag-dnanin-yapisi-nasil-cozuldu","tag-james-watson","tag-kristalografi","tag-maurice-wilkins"],"_links":{"self":[{"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/posts\/2404","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/comments?post=2404"}],"version-history":[{"count":0,"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/posts\/2404\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/media?parent=2404"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/categories?post=2404"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/tags?post=2404"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}