I-DNA ichaziwe kwaye yavavanywa

Umxholo

• Malunga neDNA
• I-DNA kwimpilo, kwizifo, nasekugugeni
• I-genome yakho eyandisiweyo
• Umonakalo weDNA kunye notshintsho
• I-DNA kunye nokuguga
• Yenziwe ntoni iDNA?
• Ijongeka kanjani i-DNA?
• Wenza ntoni iDNA?
• I-DNA inceda umzimba wakho ukuba ukhule
• Ufumana njani ukusuka kwikhowudi ye-DNA ukuya kwiprotein?
• Ifumaneka phi iDNA?
• Iiseli ze-Eukaryotic
• Iiseli zeprokaryotic
• Kwenzeka ntoni xa iiseli zakho zahlula?
• Yise kude

Kutheni iDNA ibaluleke kangaka? Ngamafutshane, iDNA inemiyalelo eyimfuneko ebomini.

Ikhowudi engaphakathi kwi-DNA yethu ibonelela ngendlela yokwenza iiproteni ezibalulekileyo ekukhuleni kwethu, ukukhula, kunye nakwimpilo yonke.

Malunga neDNA

IDNA imele i-deoxyribonucleic acid. Yenziwe ziiyunithi zeebhloko zokwakha zebhayoloji ezibizwa ngokuba zii-nucleotides.

I-DNA yimolekyuli ebaluleke kakhulu ayisiyomntu kuphela, kodwa ininzi nezinye izinto eziphilayo. I-DNA iqulethe izinto esizizuz 'ilifa kunye nofuzo- yeyona nto isenza sahluke.

Kodwa ithini iDNA yenza? Qhubeka ufunda ukuze ufumane okungakumbi malunga nobume be-DNA, into eyenzayo, kwaye kutheni ibaluleke kangaka.

I-DNA kwimpilo, kwizifo, nasekugugeni

I-genome yakho eyandisiweyo

Iseti epheleleyo yeDNA yakho ibizwa ngokuba yigenome yakho. Ineziseko zeebhiliyoni ezi-3, ii-20,000 zemfuza, kunye nee-chromosomes ezingama-23!

Ufumana ilifa lesiqingatha seDNA yakho kutata wakho nesiqingatha sikanyoko. Le DNA ivela kwisidoda kunye neqanda, ngokwahlukeneyo.

Imfuza ngokwenyani yenza i-genome encinci kakhulu-ipesenti enye kuphela. Ezinye iipesenti ezingama-99 zinceda ukulawula izinto ezinje xa ziveliswa, njani, kwaye nangobungakanani beeprotein eziveliswayo.

Izazinzulu zisafunda ngakumbi nangakumbi ngale "non-coding" ye-DNA.

Umonakalo weDNA kunye notshintsho

Ikhowudi ye-DNA ithambekele ekonakaleni. Ngapha koko, kuqikelelwa ukuba amashumi amawaka ezinto ezonakalisa iDNA zenzeka mihla le kwiseli nganye yethu. Ukonakala kunokwenzeka ngenxa yezinto ezinjengeempazamo ekuphindaphindweni kwe-DNA, ii-radicals zasimahla kunye nokuchazwa kwimitha ye-UV.

Kodwa ungoyiki! Iiseli zakho zineeproteni ezikhethekileyo ezikwaziyo ukubona nokulungisa iimeko ezininzi zomonakalo weDNA. Ngapha koko, kukho iindlela ezintlanu eziphambili zokulungiswa kwe-DNA.

Utshintsho kutshintsho kulandelelwano lwe-DNA. Ngamanye amaxesha banokuba babi. Kungenxa yokuba utshintsho kwikhowudi ye-DNA lunokuba nefuthe elisezantsi kwindlela eyenziwe ngayo iprotein.

Ukuba iprotheni ayisebenzi kakuhle, isifo sinokubangela. Eminye imizekelo yezifo ezenzeka ngenxa yotshintsho kuhlobo olunye zibandakanya i-cystic fibrosis kunye ne-sickle cell anemia.

Ukutshintsha komzimba kunokukhokelela kuphuhliso lomhlaza. Umzekelo, ukuba ukufakwa kweekhowudi kwiiproteni ezibandakanyeka ekukhuleni kweselula kuguqukile, iiseli zinokukhula kwaye zahlulelene ngaphandle kolawulo. Olunye uguquko olubangela umhlaza lunokufunyanwa njengelifa ngelixa abanye banokufunyanwa ngokuvezwa kweecarcinogens ezinje ngemitha ye-UV, imichiza, okanye umsi wecuba.

Kodwa ayizizo zonke iinguqulelo ezimbi. Sibafumana ngalo lonke ixesha. Ezinye azinabungozi ngelixa ezinye zinegalelo kukwahluka kwethu njengohlobo.

Utshintsho olwenzeka ngaphezulu kwepesenti enye yabemi kuthiwa zii-polymorphisms. Imizekelo yeepolymophisms zizinwele kunye nombala wamehlo.

I-DNA kunye nokuguga

Kukholelwa ukuba umonakalo we-DNA ongalungiswanga unokuqokelela njengoko sikhula, ukunceda ukuqhuba inkqubo yokuguga. Zeziphi izinto ezinokuba nefuthe koku?

Into enokudlala indima enkulu kumonakalo we-DNA onxulumene nokuguga ngumonakalo ngenxa yeeradicals zasimahla. Nangona kunjalo, le ndlela inye yomonakalo isenokungonelisi ukuchaza inkqubo yokwaluphala. Zininzi izinto ezinokuthi zibandakanyeke.

Inye yesizathu sokuba umonakalo we-DNA uqokelele njengoko sineminyaka yobudala isekwe kwindaleko. Kucingelwa ukuba umonakalo we-DNA ulungiswa ngokuthembeka xa sikubudala bokuzala kwaye sinabantwana. Emva kokuba sidlulile iminyaka yethu ephezulu yokuzala, inkqubo yokulungisa iyehla ngokwendalo.

Elinye icandelo le-DNA elinokuthi libandakanyeke ekugugeni zii-telomeres. IiTelomeres zolulelwano lokuphindaphindeka kolandelelwano lweDNA olufumaneka kwiziphelo zechromosomes zakho. Banceda ukukhusela i-DNA kumonakalo, kodwa banciphisa kwakhona umjikelo ngamnye wokuphindaphindeka kwe-DNA.

Ukunciphisa i-Telomere kudibene nenkqubo yokuguga. Kufunyenwe ukuba ezinye izinto zokuphila ezifana nokutyeba kakhulu, ukubhencwa kumsi wecuba, kunye noxinzelelo lwengqondo kunokuba negalelo ekunciphiseni i-telomere.

Mhlawumbi ukwenza ukhetho lokuphila ngendlela enempilo njengokugcina ubunzima obunempilo, ukulawula uxinzelelo, kunye nokungatshayi kunokucutha ukunciphisa i-telomere? Lo mbuzo uyaqhubeka unomdla omkhulu kubaphandi.

Yenziwe ntoni iDNA?

Imolekyuli ye-DNA yenziwe zii-nucleotide. I-nucleotide nganye inezinto ezintathu ezahlukeneyo - iswekile, iqela le-phosphate, kunye nesiseko se-nitrogen.

Iswekile kwi-DNA ibizwa ngokuba yi-2’-deoxyribose. Ezi molekyuli zeswekile ziyashintshana namaqela e-phosphate, enza "umqolo" womtya we-DNA.

Iswekile nganye kwi-nucleotide inesiseko se-nitrogen eqhotyoshelwe kuyo. Zine iindidi ezahlukeneyo zeesitrogen ezifumaneka kwiDNA. Ziquka:

• iadenine (A)
• icytosine (C)
• iguanine (G)
• ithmine (T)

Ijongeka kanjani i-DNA?

Imicu emibini ye-DNA yenza ubume be-3-D ebizwa ngokuba yi-helix ephindwe kabini. Xa kubonisiwe, kujongeka ngathi yileli ethe yajijwa ukuba ijikeleze apho izibini ezisisiseko ziirung kunye neeswekile phosphate backbones yimilenze.

Ukongeza, kufanelekile ukuba uqaphele ukuba i-DNA kwi-nucleus yeeseli ze-eukaryotic ilayini, oko kuthetha ukuba iziphelo zomtya ngamnye zisimahla. Kwiseli yeprokaryotic, iDNA yenza isakhiwo setyhula.

Wenza ntoni iDNA?

I-DNA inceda umzimba wakho ukuba ukhule

I-DNA iqulethe imiyalelo eyimfuneko kwinto ephilayo- wena, intaka, okanye isityalo umzekelo- ukukhula, ukukhula nokuzala. Le miyalelo igcinwe kulandelelwano lwezibini zesiseko se-nucleotide.

Iiseli zakho zifunde le khowudi iziseko ezintathu ngexesha ukuze zivelise iiproteni ezibalulekileyo ekukhuleni nasekusindeni. Ulandelelwano lwe-DNA eligcina ulwazi lokwenza iprotein kuthiwa ngumfuzo.

Iqela ngalinye leziseko ezintathu lihambelana nee-amino acid ezithile, ezizibhloko zokwakha zeeproteni. Umzekelo, izibini ezisisiseko TGG zichaza i-amino acid tryptophan ngelixa izibini ezisisiseko ze-GC zichaza i-amino acid glycine.

Olunye udibaniso, olunjenge-AA, T-A-G, kunye ne-TRA, lukwabonisa ukuphela kokulandelelana kweprotein. Oku kuxelela iseli ukuba ingongezi ezinye ii-amino acid kwiproteni.

Iiproteni zenziwe ngokudityaniswa ezahlukeneyo kweeamino acid. Xa zibekwe ndawonye ngolungelelwano oluchanekileyo, iprotheyini nganye inesakhiwo esikhethekileyo kunye nokusebenza emzimbeni wakho.

Ufumana njani ukusuka kwikhowudi ye-DNA ukuya kwiprotein?

Ukuza kuthi ga ngoku, sifundile ukuba iDNA inekhowudi enika ulwazi lweseli malunga nendlela yokwenza iiproteni. Kodwa kwenzeka ntoni phakathi? Ukubeka ngokulula, oku kwenzeka ngenkqubo yamanyathelo amabini:

Okokuqala, imicu emibini ye-DNA yahlukana. Emva koko, iiproteni ezikhethekileyo ngaphakathi kwenucleus zifunde izibini ezikwisiseko se-DNA ukwenza i-molekyuli yomthunywa ophakathi.

Le nkqubo ibizwa ngokuba kukukhutshelwa kwaye imolekyuli eyenziweyo ibizwa ngokuba ngumthunywa weRNA (mRNA). I-mRNA lolunye uhlobo lwe-acid ye-nucleic kwaye yenza kanye oko kuthethwa ligama layo. Ihamba ngaphandle kwenucleus, isebenza njengomyalezo kumatshini weselula owakha iiproteni.

Kwinyathelo lesibini, izinto ezikhethekileyo zeseli zifunda umyalezo we-mRNA isibini esisezantsi ngexesha kwaye zisebenza ukudibanisa iproteni, i-amino acid yi-amino acid. Le nkqubo ibizwa ngokuba yinguqulelo.

Ifumaneka phi iDNA?

Impendulo yalo mbuzo inokuxhomekeka kuhlobo lomzimba othetha ngawo. Zimbini iintlobo zeseli- i-eukaryotic kunye neprokaryotic.

Kubantu, kukho iDNA kwiseli nganye yethu.

Iiseli ze-Eukaryotic

Abantu kunye nezinye izinto eziphilayo baneeseli ze-eukaryotic. Oku kuthetha ukuba iiseli zazo zine-nucleus eboshwe ngombhobho kunye nezinye izinto ezibophelelweyo ezibizwa ngokuba zii-organelles.

Kwiseli ye-eukaryotic, iDNA iphakathi kwenucleus. Inani elincinci le-DNA likwafumaneka kwi-organelles ebizwa ngokuba yimitochondria, eziyizindlu zamandla zeseli.

Ngenxa yokuba kukho isixa esilinganiselweyo sendawo ngaphakathi kwenucleus, iDNA kufuneka ibotshelelwe ngokuqinileyo. Kukho amanqanaba ahlukeneyo okupakisha, nangona kunjalo iimveliso zokugqibela zizinto esizibiza ngokuba ziichromosomes.

Iiseli zeprokaryotic

Izinto ezinjengeebhaktheriya ziiseli zeprokaryotic. Ezi seli azinayo i-nucleus okanye i-organelles. Kwiiseli zeprokaryotic, iDNA ifunyenwe iboshwe ngokuqinileyo embindini weseli.

Kwenzeka ntoni xa iiseli zakho zahlula?

Iiseli zomzimba wakho zahlulahlulwe njengenxalenye yesiqhelo yokukhula nokukhula. Xa oku kusenzeka, iseli nganye entsha kufuneka ibe nekopi epheleleyo ye-DNA.

Ukuphumeza oku, iDNA yakho kufuneka yenze inkqubo ebizwa ngokuba kukuphindaphindeka. Xa oku kusenzeka, imitya emibini ye-DNA yahlukana. Emva koko, iiproteni ezikhethekileyo zeselfowuni zisebenzisa umtya ngamnye njengetemplate yokwenza umtya omtsha we-DNA.

Xa ukuphinda kugqityiwe kugqityiwe, zimbini ii-molekyuli eziboshwe kabini ze-DNA. Iseti enye iya kungena kwiseli nganye entsha xa ukwahlula kugqityiwe.

Yise kude

I-DNA ibalulekile ekukhuleni kwethu, ekuzaleni nasekuphiliseni. Inemiyalelo eyimfuneko kwiiseli zakho ukuvelisa iiproteni ezichaphazela iinkqubo ezininzi ezahlukeneyo kunye nemisebenzi emzimbeni wakho.

Ngenxa yokuba i-DNA ibaluleke kakhulu, ukonakala okanye utshintsho olunokuthi ngamanye amaxesha lube negalelo kuphuhliso lwezifo. Nangona kunjalo, kubalulekile ukuba ukhumbule ukuba uguquko lunokuba luncedo kwaye lube negalelo kukwahluka kwethu ngokunjalo.