A tsarin da DNA kunshi ... sinadaran abun da ke ciki na DNA

Mutane da yawa sun yaushe mamakin me ya sa wasu alamu akwai da iyaye ba da yaro (misali, ido launi, gashi, fuska siffar, da sauransu). Kimiyya da aka tabbatar da cewa canja halayyar dogara a kan kwayoyin abu, ko DNA.

Mene ne DNA?

A halin yanzu, a karkashin deoxyribonucleic acid fahimta hadaddun fili cewa shi ne alhakin da watsa hereditary halaye. Wannan kwayoyin samu a kowane cell na jikin mu. Yana kaddara da babban fasali na jikin mu (domin cin gaban wani hali yayi dace da takamaiman gina jiki).

Menene kunshi? A tsarin da DNA kunshi hadadden mahadi - nucleotides. By block ake nufi nucleotide ko mini fili da ciwon a cikin tsarin da nitrogenous tushe, da saura na phosphoric acid da kuma sukari (a cikin wannan harka - deoxyribose).

DNA ne biyu stranded kwayoyin, a cikinsa kowane daga cikin haihuwarka haɗa zuwa wasu ta hanyar da nitrogen da kwasfansu na da manufa na complementarity.

Bugu da ƙari kuma, shi za a iya zaci cewa a cikin DNA ya hada da genes - takamaiman nucleotide jerin alhakin gina jiki kira. Mene ne sinadaran Properties na tsarin deoxyribonucleic acid ne?

nucleotide

Kamar yadda aka ambata, da asali tsarin naúrar na deoxyribonucleic acid ne nucleotide. Wannan shi ne wani hadadden mahaluži. Abun da ke ciki na da wadannan DNA nucleotide.

A cibiyar ne biyar-bangaren nucleotide sugar (deoxyribose a DNA ne bambanci ga RNA, wanda ya ƙunshi ribose). Don shi ne shiga cikin nitrogenous tushe, wanda aka ware 5 iri: adenine, Bibyun, taimain, uracil da saitosin. Bugu da ƙari, kowane nucleotide ne hada da saura phosphoric acid.

A tsarin da DNA kunshi kawai ne ga waɗanda nucleotides cewa suna da nuna tsarin naúrar.

All nucleotides ana shirya a sarkar da kuma bin juna. Ra'ayoyi na triplets (uku nucleotides), sai suka samar da wani jerin a cikin abin da kowane triplet m zuwa wani amino acid. A sakamakon haka ne sarkar.

Sun shiga tare ta hanyar sadarwa na nitrogen sansanonin. Ainihin dangantaka tsakanin nucleotides a layi daya haihuwarka - hydrogen.

Nucleotide jerin su ne tushen genes. Take hakkin a cikin tsarin, abu don maye a cikin kira na sunadaran da bayyanuwar maye gurbi. A tsarin da DNA kunshi guda genes cewa ƙayyade kusan dukkan mutane da kuma bambanta su daga sauran kwayoyin.

gyara na wani nucleotide

A wasu lokuta, don more barga canja wuri na wani hali gyara na nitrogenous tushe da ake amfani. A sunadarai abun da ke ciki na DNA da aka modified da aka makala na wani methyl kungiyar (CH3). Irin wannan canji (daya nucleotide) damar zuwa dattako gene magana da kuma canja wurin halaye ya Kwayoyin.

Wannan "kyautata" daga cikin kwayoyin tsarin ba zai tasiri a jam'iyya na nitrogenous sansanonin.

Wannan canji da aka yi amfani da tare da X-chromosome inactivation. A sakamakon haka, kafa Barr jiki.

A hali na ta ƙara carcinogenesis DNA bincike ya nuna cewa sarkar da nucleotides ya batun methylation a kan da yawa substrates. A observational karatu, sai aka fahimci cewa tushen da maye gurbi ne yawanci a methylated saitosin. Yawanci a lokacin da ƙari demethylation tsari za a iya inganta tasha tsari, amma saboda cakuduwar, wannan dauki ba za'ayi.

DNA tsarin

A tsarin da kwayoyin iri biyu Tsarin. Nau'i na farko - a mikakke jerin nucleotides kafa. Su yi shi ne batun wasu dokoki. Rikodi a nucleotide jigidar halittar DNA ta fara da 5'-terminus da 3'-terminus ƙare. A na biyu kewaye located a kan m, aka gina a cikin wannan hanya, kawai a kwayoyin ne spatially gaban juna, cikinsa da 5'-terminus na daya sarkar aka located daura da 3'-karshen na biyu.

Helix - DNA sakandare tsarin. Lalacewa ta hanyar gaban hydrogen shaidu jere tsakanin adawa da nucleotides. A hydrogen bond aka kafa (kawai taimain, Bibyun da bambanci iya zama misali, m farko tufka adenine - uracil ko saitosin) tsakanin karin nitrogenous sansanonin. Irin wannan daidaito ne saboda gaskiyar cewa da shiri na biyu kewaye faruwa a kan tushen farko, don haka tsakanin nitrogenous sansanonin akwai dace.

Kira na da kwayoyin

Yaya cikin jigidar halittar DNA kafa?

A sake zagayowar na da samuwar ne matakai uku:

• Cire hašin haihuwarka.
• Accession rairaya raka'a to daya daga cikin marũruwa.
• Tsawo daga na biyu kewaye bisa ga ka'ida na complementarity.

A mataki na rabuwa da kwayoyin da aka mamaye enzymes - DNA gyrase. Wadannan enzymes suna mayar da hankali kan halakar hydrogen shaidu tsakanin sarƙoƙi.

Bayan bambanta rarrabuwar sarƙoƙi zo a cikin na asali rairaya enzyme - DNA polymerase. Its riko da aka lura a wani site 5 '. Next, da enzyme ne motsi wajen 3'-karshen, a lokaci guda attaching da ake buƙata nucleotides tare dace nitrogenous sansanonin. Bayan kai da qaddara range (terminator) a 3 'karshen, polymerase sarkar aka cire ta daga Madogararsa.

Da zarar kafa na biyu kewaye tsakanin sansanonin samar da hydrogen shaidu, da kuma wanda yake riƙe da sabuwar kafa jigidar halittar DNA.

Ina zan iya samun wannan kwayoyin?

Idan ka shiga cikin tsarin da Kwayoyin kuma tsokoki, da shi za a iya gani cewa DNA da aka yafi samu a cikin cell tsakiya. Kwaya ne ke da alhakin samuwar sabuwar rassa, Kwayoyin ko su kwafi masu kunnen doki. Kamar wancan kayyade bayanai gabatar a cikinta, aka raba tsakanin sabuwar kafa Kwayoyin gaba ɗaya (generated kwafi masu kunnen doki) ko partially (sau da yawa za a lura irin wannan sabon abu a lokacin meiosis). Da shan kashi na core sakamakon a wani take hakkin da samuwar sabuwar nama, wadda take kaiwa zuwa maye gurbi.

Bugu da kari, musamman irin hereditary kayan dauke a cikin mitochondria. Sun DNA ɗan daban-daban daga cewa a cikin nucleus din (mitochondrial deoxyribonucleic acid yana da wani annular siffar kuma ya aikata aikin da dama wasu ayyuka).

Kwayar Komayya kanta za a iya ware daga duk wani cell na jiki (a nazarin da aka fi amfani swab daga cikin ciki na kunci ko jini). Babu kwayoyin abu kawai a cikin epithelium exfoliates da kuma wasu da maikacin jini (erythrocytes).

ayyuka

A abun da ke ciki na cikin jigidar halittar DNA kayyade yi ta watsa bayanai aiki daga tsara zuwa tsara. Wannan shi ne saboda da kira na wasu sunadarai da kai ga bayyanuwar mai genotype (ciki) ko phenotypic (external - misali, launi da idanu ko gashi) fasalin.

The watsa bayanai ne da za'ayi ta hanyar aiwatar da ta kayyade code. A kan tushen da data rufaffen a cikin kwayoyin code, akwai wani ci gaban da takamaiman bayani, ribosomal da kuma canja wurin RNA. Kowane daga cikinsu shi ne alhakin da wani takamaiman mataki - manzo RNA da ake amfani da haduwa da sunadarai da hannu a ribosomal sunadarai na gina jiki taro, da kuma Forms m kai sunadaran.

Duk wani maye a cikin aiki ko tsarin canji take kaiwa zuwa rushewa daga cikin aikin yi, da kuma bayyanar atypical siffofin (maye gurbi).

DNA ubanci gwajin domin sanin gaban related cututtuka tsakanin mutane.

kwayoyin gwaje-gwaje

Abin da a yanzu za a iya amfani da nazarin kwayoyin kaya?

DNA bincike da aka yi amfani da sanin da dama dalilai ko canje-canje a cikin kwayoyin.

A farko nazari domin sanin gaban nakasar, sun gaji cututtuka. Irin cututtuka sun hada da Down ciwo, Autism, Marfan ciwo.

Domin sanin kinship DNA kuma za a iya yi karatu. Ubanci gwajin ya dade tartsatsi a cikin da yawa, da farko doka, tafiyar matakai. Wannan binciken an wajabta, a kayyade da kwayoyin dangantaka tsakanin shege yara. Sau da yawa da wannan gwajin nema auku a kan gado a cikin taron da matsaloli tare da hukumomi.