Prokaryot ve \u00d6karyot H\u00fccrelerin Kar\u015f\u0131la\u015ft\u0131r\u0131lmas\u0131<\/p>\n
Elektron mikroskobunun geli\u015ftirilmesiyle birlikte, biyologlar h\u00fccre i\u00e7i yap\u0131lar\u0131 inceleme f\u0131rsat\u0131 buldular. Bu ara\u015ft\u0131rmalar sonunda canl\u0131lar aleminde iki temel h\u00fccre tipi oldu\u011fu ortaya \u00e7\u0131kt\u0131: prokaryotik ve \u00f6karyotik h\u00fccre. Yap\u0131sal olarak daha basit olan prokaryotik h\u00fccre yap\u0131s\u0131 sadece bakterilerde bulunur. Di\u011fer b\u00fct\u00fcn organizmalar yani protista, fungi (mantarlar), bitkiler ve hayvanlar daha karma\u015f\u0131k olan \u00f6karyotik h\u00fccre yap\u0131s\u0131na sahiptir.<\/p>\n
Evrimsel g\u00f6r\u00fc\u015f\u00fc savunan baz\u0131 bilim insanlar\u0131 \u00f6karyot ve prokaryot canl\u0131lar aras\u0131ndaki baz\u0131 genlerin benzer olmas\u0131n\u0131n, uzun zaman \u00f6nce \u00f6karyotlar\u0131n prokaryotlardan farkl\u0131la\u015fmas\u0131ndan kaynakland\u0131\u011f\u0131n\u0131 ileri s\u00fcrmektedir.
\nBuna ba\u011fl\u0131 olarak, \u00f6karyot h\u00fccrelerde bulunan kendine ait DNA ve RNA bulunduran mitokondri ve kloroplast organellerinin olu\u015fumuyla ilgili, endosimbiyoz hipotezini ortaya atm\u0131\u015flard\u0131r.<\/p>\n
Endosimbiyoz hipotezine g\u00f6re, oksijenli solunum yapan mor bakteri(prokaryot canl\u0131) \u00e7ekirde\u011fi bulunan ilkel yap\u0131l\u0131 \u00f6karyot h\u00fccreye girerek ortak bir ya\u015fama birli\u011fi olu\u015fturmu\u015ftur. Bu ortak ya\u015famda kar\u015f\u0131l\u0131kl\u0131 yarar s\u00f6z konusudur. Bakteri h\u00fccre i\u00e7in gerekli enerjiyi sentezlerken, h\u00fccre de bakteriye besin ve ya\u015fama ortam\u0131 sa\u011flam\u0131\u015ft\u0131r. B\u00f6ylece bakteri mitokondri organeli haline gelmi\u015ftir.<\/p>\n
Kloroplastlar\u0131n da benzer \u015fekilde, siyanobakterilerin ilkel yap\u0131l\u0131 \u00f6karyot h\u00fccreye girmesiyle olu\u015ftu\u011fu, b\u00f6ylece h\u00fccreye fotosentez yapabilme yetene\u011fi kazand\u0131rd\u0131\u011f\u0131 ileri s\u00fcr\u00fclmektedir.<\/p>\n
Her iki h\u00fccre tipinde ortak olan \u00f6zellikler:
\n?Benzer yap\u0131da h\u00fccre zar\u0131.
\n?Genetik bilginin DNA arac\u0131l\u0131\u011f\u0131yla kodlanmas\u0131 ve aktar\u0131lmas\u0131.
\n?Transkripsiyon ve translasyon mekanizmalar\u0131n\u0131n ve ribozomlar\u0131n benzer olmas\u0131.
\n?Ortak metabolik yollar\u0131n bulunmas\u0131.
\n(\u00f6rnek: glikoliz)
\n?Kimyasal enerjiyi ATP olarak depolamak i\u00e7in kullan\u0131lan mekanizman\u0131n benzer olmas\u0131 (prokaryotlar\u0131n h\u00fccre zar\u0131nda, \u00f6karyotlar\u0131n mitokondri zar\u0131nda).
\n?Benzer fotosentez mekanizmalar\u0131.
\n?Zar proteinlerini senaaaleme ve h\u00fccre zar\u0131na yerle\u015ftirmede kullan\u0131lan mekanizman\u0131n benzerli\u011fi.
\n?Benzer yap\u0131da proteazomlar (protein sindiren yap\u0131lar).<\/p>\n
\u00d6karyotik h\u00fccrede bulunup prokaryotlarda bulunmayan \u00f6zellikler:
\n?H\u00fccrede, \u00e7ekirdek ad\u0131 verilen ve bir zarla sitoplazmadan ayr\u0131lan bir b\u00f6l\u00fcm\u00fcn bulunmas\u0131. \u00c7ekirdek zar\u0131nda bulunan karma\u015f\u0131k yap\u0131l\u0131 porlar (delikler).
\n?DNA ile birlikte mitoz b\u00f6l\u00fcnme s\u0131ras\u0131nda s\u0131kla\u015fabilme \u00f6zelli\u011fine sahip proteinlerin bulunmas\u0131.
\n?Karma\u015f\u0131k yap\u0131l\u0131 zars\u0131 sitoplazmik organellerin bulunmas\u0131.
\n?Oksijenli solunum i\u00e7in \u00f6zelle\u015fmi\u015f sitoplazmik organeller: mitokondri.
\n?Fotosentez i\u00e7in \u00f6zelle\u015fmi\u015f sitoplazmik organeller: kloroplast.
\n?Karma\u015f\u0131k yap\u0131l\u0131 h\u00fccre iskeletinin (sitoskeleton) bulunmas\u0131. (Mikrofilamentler, ara filamentler ve mikrot\u00fcb\u00fcller)
\n?Daha karma\u015f\u0131k kam\u00e7\u0131 (flagella) yap\u0131s\u0131.
\n?H\u00fccre zar\u0131yla kesecikler olu\u015fturarak s\u0131v\u0131 ve kat\u0131 maddeleri h\u00fccre i\u00e7ine alabilme yetene\u011fi. (endositoz ve fagositoz)
\n?Bitkilerde sel\u00fcloz i\u00e7eren h\u00fccre duvar\u0131.
\n?H\u00fccre b\u00f6l\u00fcnmesi s\u0131ras\u0131nda kromozomlar\u0131n ayr\u0131lmas\u0131n\u0131 sa\u011flayan ve mikrot\u00fcb\u00fcl yap\u0131da olan i\u011f iplikleri.
\n?Diploidlik: her h\u00fccrede bir genin iki kopya halinde bulunmas\u0131.
\n?Mayoz b\u00f6l\u00fcnme ve d\u00f6llenme gerektiren e\u015feyli \u00fcreme.<\/p>\n","protected":false},"excerpt":{"rendered":"
Prokaryot ve \u00d6karyot H\u00fccrelerin Kar\u015f\u0131la\u015ft\u0131r\u0131lmas\u0131 Elektron mikroskobunun geli\u015ftirilmesiyle birlikte, biyologlar h\u00fccre i\u00e7i yap\u0131lar\u0131 inceleme f\u0131rsat\u0131 buldular. Bu ara\u015ft\u0131rmalar sonunda canl\u0131lar aleminde iki temel h\u00fccre tipi oldu\u011fu ortaya \u00e7\u0131kt\u0131: prokaryotik ve \u00f6karyotik h\u00fccre. Yap\u0131sal olarak daha basit olan prokaryotik h\u00fccre yap\u0131s\u0131 sadece bakterilerde bulunur. Di\u011fer b\u00fct\u00fcn organizmalar yani protista, fungi (mantarlar), bitkiler ve hayvanlar daha karma\u015f\u0131k … Devam\u0131n\u0131 oku…<\/a><\/p>\n","protected":false},"author":1685,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[44],"tags":[16286,16285],"_links":{"self":[{"href":"https:\/\/www.sorubak.com\/blog\/wp-json\/wp\/v2\/posts\/42542"}],"collection":[{"href":"https:\/\/www.sorubak.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.sorubak.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.sorubak.com\/blog\/wp-json\/wp\/v2\/users\/1685"}],"replies":[{"embeddable":true,"href":"https:\/\/www.sorubak.com\/blog\/wp-json\/wp\/v2\/comments?post=42542"}],"version-history":[{"count":0,"href":"https:\/\/www.sorubak.com\/blog\/wp-json\/wp\/v2\/posts\/42542\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.sorubak.com\/blog\/wp-json\/wp\/v2\/media?parent=42542"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.sorubak.com\/blog\/wp-json\/wp\/v2\/categories?post=42542"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.sorubak.com\/blog\/wp-json\/wp\/v2\/tags?post=42542"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}