{"id":22794,"date":"2018-01-26T00:31:33","date_gmt":"2018-01-26T00:31:33","guid":{"rendered":"http:\/\/www.fjala.info\/?p=22794"},"modified":"2020-04-08T14:54:05","modified_gmt":"2020-04-08T13:54:05","slug":"si-ka-filluar-jeta-ne-toke","status":"publish","type":"post","link":"https:\/\/jehonashqiptare.al\/fjala\/si-ka-filluar-jeta-ne-toke\/","title":{"rendered":"SI KA FILLUAR JETA N\u00cb TOK\u00cb? – nj\u00eb artikull i BBC b\u00ebn sqarimin shkencor"},"content":{"rendered":"

Nga\u00a0Michael Marshall<\/strong>, 31 tetor 2016<\/em><\/p>\n

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P\u00ebrktheu dhe p\u00ebrgatiti n\u00eb shqip, Arben \u00c7okaj<\/strong><\/em><\/p>\n<\/blockquote>\n

Kjo histori \u00ebsht\u00eb pjes\u00eb e list\u00ebs s\u00eb BBC p\u00ebr Tok\u00ebn “M\u00eb e mira p\u00ebr<\/em><\/strong>\u00a02016″, rezultati m\u00eb i madh i vitit. Shfletoni list\u00ebn e plot\u00eb.<\/a><\/em><\/strong> (n\u00eb anglisht)<\/em><\/p>\n

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\"\"Charles Blomfield “Tarracat e bardha, Rotomahana” (1897)<\/em>
\n(Credit: PAINTING\/Alamy Stock Photo)<\/p>\n<\/blockquote>\n

Si filloi jeta n\u00eb tok\u00eb? Nuk mund t\u00eb ket\u00eb nj\u00eb pyetje m\u00eb t\u00eb madhe. P\u00ebr pjes\u00ebn m\u00eb t\u00eb madhe t\u00eb historis\u00eb njer\u00ebzore, pothuajse t\u00eb gjith\u00eb besonin se nj\u00eb version i “per\u00ebndive e b\u00ebri k\u00ebt\u00eb”. \u00c7do shpjegim tjet\u00ebr ishte i pakonceptuesh\u00ebm.<\/p>\n

Kjo nuk \u00ebsht\u00eb m\u00eb e v\u00ebrtet\u00eb<\/strong>. Gjat\u00eb shekullit t\u00eb kaluar, disa shkenc\u00ebtar\u00eb jan\u00eb p\u00ebrpjekur t\u00eb kuptojn\u00eb se si mund t\u00eb ket\u00eb dal\u00eb jeta e par\u00eb. Ata madje u p\u00ebrpoq\u00ebn t\u00eb rikrijojn\u00eb k\u00ebt\u00eb moment Zanafille n\u00eb laborator\u00ebt e tyre: t\u00eb krijojn\u00eb nj\u00eb jet\u00eb krejt t\u00eb re nga e para.<\/p>\n

Deri m\u00eb tani askush nuk e kan\u00eb arritur at\u00eb, por kemi arritur nj\u00eb rrug\u00eb t\u00eb gjat\u00eb. Sot, shum\u00eb nga shkenc\u00ebtar\u00ebt q\u00eb studiojn\u00eb origjin\u00ebn e jet\u00ebs jan\u00eb t\u00eb bindur se jan\u00eb n\u00eb rrug\u00ebn e duhur – dhe kan\u00eb eksperimente p\u00ebr ta mb\u00ebshtetur besimin e tyre.<\/p>\n

Kjo \u00ebsht\u00eb historia e p\u00ebrpjekjes son\u00eb p\u00ebr t\u00eb zbuluar origjin\u00ebn ton\u00eb t\u00eb fundit. Kjo \u00ebsht\u00eb nj\u00eb histori e obsesionit, luft\u00ebs dhe krijimtaris\u00eb s\u00eb shk\u00eblqyer, e cila p\u00ebrfshin disa nga zbulimet m\u00eb t\u00eb m\u00ebdha t\u00eb shkenc\u00ebs moderne. P\u00ebrpjekja p\u00ebr t\u00eb kuptuar fillimet e jet\u00ebs ka d\u00ebrguar burra dhe gra n\u00eb skajet m\u00eb t\u00eb larg\u00ebta t\u00eb planetit ton\u00eb. Disa nga shkenc\u00ebtar\u00ebt e p\u00ebrfshir\u00eb jan\u00eb shtangur si p\u00ebrbind\u00ebsha, nd\u00ebrsa t\u00eb tjer\u00ebt duhej t\u00eb b\u00ebnin pun\u00ebn e tyre n\u00ebn thembra t\u00eb qeverive brutale totalitare.<\/p>\n

Kjo \u00ebsht\u00eb historia e lindjes s\u00eb jet\u00ebs n\u00eb Tok\u00eb.<\/p>\n

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\"\"Dinosaur\u00ebt jetuan aktualisht mjaft koh\u00eb m\u00eb par\u00eb<\/em> (Credit: Oleksiy Maksymenko\/Alamy)<\/p>\n<\/blockquote>\n

Jeta \u00ebsht\u00eb e vjet\u00ebr. Dinosaur\u00ebt ndoshta jan\u00eb krijesat m\u00eb t\u00eb njohura t\u00eb zhdukura dhe fillimet e tyre kan\u00eb qen\u00eb 250 milion\u00eb vjet m\u00eb par\u00eb. Por jeta daton shum\u00eb m\u00eb tej.<\/p>\n

Fosilet m\u00eb t\u00eb vjet\u00ebr<\/a> t\u00eb njohur jan\u00eb rreth 3.5 miliard\u00eb vje\u00e7, 14 her\u00eb m\u00eb t\u00eb vjet\u00ebr se dinosaur\u00ebt m\u00eb t\u00eb vjet\u00ebr. Por t\u00eb dh\u00ebnat fosile mund t\u00eb shtrihen p\u00ebrs\u00ebri m\u00eb tej. P\u00ebr shembull, n\u00eb gusht t\u00eb vitit 2016, hulumtuesit gjet\u00ebn ato q\u00eb duket t\u00eb jen\u00eb fosile t\u00eb fosilizuara<\/a> q\u00eb datojn\u00eb 3.7 miliard\u00eb vjet<\/a> m\u00eb par\u00eb.<\/p>\n

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\"\"<\/a>K\u00ebto modele t\u00eb val\u00ebzuara mund t\u00eb jen\u00eb fosile 3.7 miliard\u00eb vje\u00e7are<\/em>
\n(Credit: Nutman et al, Nature)<\/p>\n<\/blockquote>\n

Vet\u00eb Toka nuk \u00ebsht\u00eb shum\u00eb m\u00eb e vjet\u00ebr, duke u formuar 4.5 miliard vjet m\u00eb par\u00eb.<\/p>\n

N\u00ebse supozojm\u00eb se jeta e formuar n\u00eb Tok\u00eb – e cila duket e arsyeshme, duke pasur parasysh se nuk e kemi gjetur akoma diku tjet\u00ebr<\/a> – at\u00ebher\u00eb duhet t\u00eb ket\u00eb b\u00ebr\u00eb k\u00ebshtu n\u00eb miliarda vjet midis Tok\u00ebs q\u00eb po lindte dhe ruajtjes s\u00eb fosileve m\u00eb t\u00eb vjetra t\u00eb njohura.<\/p>\n

Si dhe duke u fokusuar kur filloi jeta, ne mund t\u00eb arrijm\u00eb n\u00eb nj\u00eb mendim t\u00eb arsimuar, n\u00eb at\u00eb q\u00eb ishte.<\/p>\n

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\"\"Pema e jet\u00ebs: shumica e deg\u00ebve jan\u00eb baktere
\n<\/em>(Credit: Hug, Banfield et al, Nature Microbiology)<\/p>\n<\/blockquote>\n

Q\u00eb nga shekulli i 19-t\u00eb, biolog\u00ebt kan\u00eb njohur se t\u00eb gjitha gjallesat jan\u00eb b\u00ebr\u00eb nga “qelizat”: \u00e7anta t\u00eb vogla t\u00eb materialit t\u00eb gjall\u00eb, q\u00eb vijn\u00eb n\u00eb forma dhe madh\u00ebsi t\u00eb ndryshme. Qelizat u zbuluan s\u00eb pari n\u00eb shekullin e 17-t\u00eb, kur u zbuluan mikroskop\u00ebt e par\u00eb modern\u00eb, por u desh m\u00eb shum\u00eb se nj\u00eb shekull p\u00ebr t\u00eb kuptuar se ata ishin baza e gjith\u00eb jet\u00ebs.<\/p>\n

Duke p\u00ebrdorur vet\u00ebm materialet dhe kushtet e gjetura n\u00eb Tok\u00eb mbi 3.5 miliard vjet m\u00eb par\u00eb, ne duhet t\u00eb b\u00ebjm\u00eb nj\u00eb qeliz\u00eb<\/em><\/p><\/blockquote>\n

Ju nuk mund t\u00eb mendoni se ju duken shum\u00eb si nj\u00eb mustak ose nj\u00eb rex Tyrannosaurus, por nj\u00eb mikroskop do t\u00eb zbuloj\u00eb se t\u00eb gjith\u00eb ju jeni b\u00ebr\u00eb nga qeliza mjaft t\u00eb ngjashme. K\u00ebshtu jan\u00eb edhe bim\u00ebt dhe k\u00ebrpudhat.<\/p>\n

Por, deri tani, format m\u00eb t\u00eb shumta t\u00eb jet\u00ebs jan\u00eb mikroorganizmat, secila prej t\u00eb cilave p\u00ebrb\u00ebhet nga vet\u00ebm nj\u00eb qeliz\u00eb. Bakteret jan\u00eb grupi m\u00eb i famsh\u00ebm dhe gjenden kudo n\u00eb Tok\u00eb.<\/p>\n

N\u00eb prill t\u00eb vitit 2016, shkenc\u00ebtar\u00ebt paraqit\u00ebn nj\u00eb version t\u00eb p\u00ebrdit\u00ebsuar t\u00eb “pem\u00ebs s\u00eb jet\u00ebs”<\/a>: nj\u00eb lloj peme familjare p\u00ebr \u00e7do specie t\u00eb gjall\u00eb. Pothuajse t\u00eb gjitha deg\u00ebt jan\u00eb baktere. P\u00ebr m\u00eb tep\u00ebr, forma e pem\u00ebs sugjeron se nj\u00eb bakter \u00ebsht\u00eb paraardh\u00ebsi i p\u00ebrbashk\u00ebt i t\u00eb gjith\u00eb jet\u00ebs. Me fjal\u00eb t\u00eb tjera, \u00e7do gj\u00eb e gjall\u00eb – p\u00ebrfshir\u00eb edhe ju – p\u00ebrfundimisht zbritet te nj\u00eb bakter.<\/p>\n

Kjo do t\u00eb thot\u00eb q\u00eb ne mund ta p\u00ebrcaktojm\u00eb m\u00eb sakt\u00eb problemin e origjin\u00ebs s\u00eb jet\u00ebs. Duke p\u00ebrdorur vet\u00ebm materialet dhe kushtet e gjetura n\u00eb Tok\u00eb mbi 3.5 miliard vjet m\u00eb par\u00eb, ne duhet t\u00eb b\u00ebjm\u00eb nj\u00eb qeliz\u00eb.<\/p>\n

Epo, sa e v\u00ebshtir\u00eb mund t\u00eb jet\u00eb?<\/p>\n

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\"\"Nj\u00eb qeliz\u00eb e plot\u00eb, e gjall\u00eb (Credit: Equinox Graphics Ltd)<\/em><\/p>\n<\/blockquote>\n

Kapitulli 1. Eksperimentet e para<\/strong><\/p>\n

P\u00ebr pjes\u00ebn m\u00eb t\u00eb madhe t\u00eb historis\u00eb, nuk konsiderohej me t\u00eb v\u00ebrtet\u00eb e nevojshme p\u00ebr t\u00eb pyetur se si filloi jeta, sepse p\u00ebrgjigja dukej e dukshme.<\/p>\n

Para viteve 1800, shumica e njer\u00ebzve besonin n\u00eb “vitalizmin”. Kjo \u00ebsht\u00eb ideja intuitive se gj\u00ebrat e gjalla ishin t\u00eb pajisura me nj\u00eb pasuri t\u00eb ve\u00e7ant\u00eb magjike, q\u00eb i b\u00ebnte ata t\u00eb ndrysh\u00ebm nga sendet e pajet\u00eb.<\/p>\n

Kimikatet e jet\u00ebs mund t\u00eb b\u00ebhen t\u00eb gjitha nga kimikate m\u00eb t\u00eb thjeshta q\u00eb nuk kan\u00eb t\u00eb b\u00ebjn\u00eb me jet\u00ebn<\/em><\/p><\/blockquote>\n

Vitalizmi shpesh lidhej me besimet fetare t\u00eb \u00e7muara. Bibla thot\u00eb se Per\u00ebndia p\u00ebrdori \u00abfrym\u00ebn e jet\u00ebs<\/a>\u00bb p\u00ebr t\u00eb animuar njer\u00ebzit e par\u00eb dhe shpirti i pavdeksh\u00ebm \u00ebsht\u00eb nj\u00eb form\u00eb vitalizmi.<\/p>\n

Ekziston vet\u00ebm nj\u00eb problem. Vitalizmi \u00ebsht\u00eb i gabuar.<\/p>\n

Deri n\u00eb fillim t\u00eb viteve 1800, shkenc\u00ebtar\u00ebt kishin zbuluar disa substanca, q\u00eb dukeshin t\u00eb jen\u00eb unike p\u00ebr jet\u00ebn. Nj\u00eb kimik i till\u00eb ishte ure, e cila gjendet n\u00eb urin\u00eb dhe u izolua n\u00eb 1799.<\/p>\n

Kjo ishte akoma, e drejt\u00eb, e pajtueshme me vitalizmin. Vet\u00ebm gj\u00ebrat e gjalla dukeshin t\u00eb jen\u00eb n\u00eb gjendje t’i b\u00ebjn\u00eb k\u00ebto kimikate, k\u00ebshtu q\u00eb ndoshta ata ishin t\u00eb mbushur me energji jet\u00ebsore dhe kjo ishte ajo q\u00eb i b\u00ebri ata t\u00eb ve\u00e7ant\u00eb.<\/p>\n

Por n\u00eb 1828, kimisti gjerman Friedrich W\u00f6hler<\/strong> gjeti nj\u00eb m\u00ebnyr\u00eb p\u00ebr t\u00eb b\u00ebr\u00eb ure nga nj\u00eb kombinim kimik i zakonsh\u00ebm i quajtur cianati i amoniakut<\/a>, i cili nuk kishte lidhje t\u00eb dukshme me gjallesat. T\u00eb tjer\u00eb e ndoq\u00ebn gjurm\u00ebt e tij dhe shpejt u zbulua se kimikatet e jet\u00ebs mund t\u00eb b\u00ebhen t\u00eb gjitha nga kimikate m\u00eb t\u00eb thjeshta, q\u00eb nuk kan\u00eb t\u00eb b\u00ebjn\u00eb me jet\u00ebn.<\/p>\n

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\"\"Kimisti gjerman Friedrich W\u00f6hler, n\u00eb nj\u00eb litografi nga Rudolf Hoffmann m\u00eb 1856<\/em><\/p>\n<\/blockquote>\n

Ky ishte fundi i vitalizmit si nj\u00eb koncept shkencor. Por njer\u00ebzit e gjet\u00ebn at\u00eb thell\u00ebsisht t\u00eb v\u00ebshtir\u00eb p\u00ebr t’u larguar nga ideja. P\u00ebr shum\u00eb njer\u00ebz, duke th\u00ebn\u00eb se nuk ka asgj\u00eb “t\u00eb ve\u00e7ant\u00eb” n\u00eb lidhje me kimikatet e jet\u00ebs dukej se vjedh jet\u00ebn e magjis\u00eb s\u00eb saj, p\u00ebr t\u00eb na zvog\u00ebluar n\u00eb makina t\u00eb thjeshta. Gjithashtu, natyrisht, kjo kund\u00ebrshtoi edhe Bibl\u00ebn.<\/p>\n

Misteri i origjin\u00ebs s\u00eb jet\u00ebs \u00ebsht\u00eb injoruar p\u00ebr dekada t\u00eb t\u00ebra<\/em><\/p><\/blockquote>\n

Edhe shkenc\u00ebtar\u00ebt kan\u00eb luftuar p\u00ebr t\u00eb hequr vitalizmin. Deri n\u00eb vitin 1913, biokimisti anglez Benjamin Moore<\/strong> po nxiste me zell nj\u00eb teori t\u00eb “energjis\u00eb biotike<\/a>“, e cila ishte n\u00eb thelb vitaliz\u00ebm n\u00ebn nj\u00eb em\u00ebr tjet\u00ebr. Ideja kishte nj\u00eb mb\u00ebrthim t\u00eb fort\u00eb emocional.<\/p>\n

Sot ideja ngjitet n\u00eb vende t\u00eb papritura. P\u00ebr shembull, ka shum\u00eb tregime shkencore-fiction n\u00eb t\u00eb cilat “energjia e jet\u00ebs” e nj\u00eb personi mund t\u00eb rritet ose t\u00eb largohet. Mendoni p\u00ebr “energjin\u00eb e rigjenerimit” q\u00eb p\u00ebrdoret nga Zot\u00ebruesit e Koh\u00ebs n\u00eb Doctor Who<\/em>, e cila madje mund t\u00eb ngrihet n\u00eb qoft\u00eb se shkon ul\u00ebt<\/a>. Kjo ndjehet futuriste, por \u00ebsht\u00eb nj\u00eb ide e mod\u00ebs s\u00eb vjet\u00ebr.<\/p>\n

Sidoqoft\u00eb, pas 1828, shkenc\u00ebtar\u00ebt kishin arsye legjitime t\u00eb k\u00ebrkonin nj\u00eb shpjegim jo-hyjnor se si u krijua jeta e par\u00eb. Por ata nuk e b\u00ebn\u00eb. Duket sikur nj\u00eb subjekt i qart\u00eb p\u00ebr t’u eksploruar, por n\u00eb t\u00eb v\u00ebrtet\u00eb misteri i origjin\u00ebs s\u00eb jet\u00ebs \u00ebsht\u00eb injoruar p\u00ebr dekada t\u00eb t\u00ebra. Ndoshta t\u00eb gjith\u00eb ishin ende tep\u00ebr t\u00eb lidhur emocionalisht me vitalizmin p\u00ebr t\u00eb nd\u00ebrmarr\u00eb hapin tjet\u00ebr.<\/p>\n

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\"\"Charles Darwin tregoi se e gjith\u00eb jeta ka evoluar nga nj\u00eb paraardh\u00ebs i thjesht\u00eb, i p\u00ebrbashk\u00ebt<\/em><\/p>\n<\/blockquote>\n

N\u00eb vend t\u00eb k\u00ebsaj, zbulimi i madh biologjik i shekullit t\u00eb 19-t\u00eb ishte teoria e evolucionit<\/a>, si\u00e7 u zhvillua nga Charles Darwin dhe t\u00eb tjer\u00ebt.<\/p>\n

Darvini e dinte se ishte nj\u00eb \u00e7\u00ebshtje e thell\u00eb<\/em><\/p><\/blockquote>\n

Teoria e Darvinit, e paraqitur n\u00eb “Nga origjina e specieve<\/em>” n\u00eb vitin 1859, shpjegoi se si shum\u00ebllojshm\u00ebria e madhe e jet\u00ebs mund t\u00eb dilte nga nj\u00eb paraardh\u00ebs i vet\u00ebm, i p\u00ebrbashk\u00ebt. N\u00eb vend t\u00eb secil\u00ebs prej llojeve t\u00eb ndryshme q\u00eb u krijuan individualisht nga Per\u00ebndia, t\u00eb gjith\u00eb ishin prej nj\u00eb organizmi fillestar, q\u00eb jetonin miliona vjet m\u00eb par\u00eb: paraardh\u00ebsi i fundit universal i p\u00ebrbashk\u00ebt.<\/p>\n

Kjo ide provoi jasht\u00ebzakonisht t\u00eb diskutueshme, p\u00ebrs\u00ebri p\u00ebr shkak se ajo ishte n\u00eb kund\u00ebrshtim edhe me Bibl\u00ebn. Darvini dhe idet\u00eb e tij u vun\u00eb n\u00ebn nj\u00eb sulm t\u00eb eg\u00ebr, ve\u00e7an\u00ebrisht nga t\u00eb krishter\u00ebt e zem\u00ebruar.<\/p>\n

Teoria e evolucionit nuk tha asgj\u00eb rreth asaj se si u krijua ai organiz\u00ebm i par\u00eb.<\/p>\n

\n

\"\"Darwin habitej, n\u00ebse jeta ka filluar n\u00eb nj\u00eb “pellg t\u00eb vog\u00ebl uji t\u00eb ngroht\u00eb”<\/em>
\n(Credit: Linda Reinink-Smith\/Alamy)<\/p>\n<\/blockquote>\n

Darvini e dinte se ishte nj\u00eb \u00e7\u00ebshtje e thell\u00eb, por – ndoshta i kujdessh\u00ebm p\u00ebr fillimin e nj\u00eb lufte tjet\u00ebr me Kish\u00ebn – ai duket se e ka diskutuar \u00e7\u00ebshtjen n\u00eb nj\u00eb let\u00ebr t\u00eb shkruar n\u00eb 1871<\/a>. Gjuha e tij e ngaz\u00ebllyer zbulon se e dinte r\u00ebnd\u00ebsin\u00eb e thell\u00eb t\u00eb pyetjes :<\/p>\n

Hipoteza e par\u00eb p\u00ebr origjin\u00ebn e jet\u00ebs u shpik n\u00eb nj\u00eb vend t\u00eb eg\u00ebr totalitar<\/em><\/p><\/blockquote>\n

“Por n\u00ebse <\/em>(dhe sa gj\u00eb e madhe kjo n\u00ebse<\/em>) ne mund t\u00eb krijojm\u00eb n\u00eb nj\u00eb pellg t\u00eb ngroht\u00eb t\u00eb vog\u00ebl me t\u00eb gjitha llojet e amoniakut dhe krip\u00ebrave fosforike, drit\u00eb, nxeht\u00ebsi, energji elektrike &c prezente, ajo p\u00ebrb\u00ebrje proteinash u formua kimikisht, e gatshme t\u00eb nd\u00ebrmarr\u00eb ndryshime t\u00eb m\u00ebtejshme komplekse…”<\/p>\n

Me fjal\u00eb t\u00eb tjera, \u00e7ka n\u00ebse<\/em> ka qen\u00eb dikur nj\u00eb trup i vog\u00ebl uji, i mbushur me komponime t\u00eb thjeshta organike dhe t\u00eb lar\u00eb n\u00eb rrezet e diellit. Disa nga k\u00ebto komponime mund t\u00eb kombinohen p\u00ebr t\u00eb formuar nj\u00eb substanc\u00eb t\u00eb ngjashme me jet\u00ebn si nj\u00eb protein\u00eb, e cila pastaj mund t\u00eb filloj\u00eb t\u00eb evoluoj\u00eb dhe t\u00eb b\u00ebhet m\u00eb komplekse.<\/p>\n

Ishte nj\u00eb ide e \u00e7uditshme. Por do t\u00eb b\u00ebhej baza e hipotez\u00ebs s\u00eb par\u00eb p\u00ebr m\u00ebnyr\u00ebn se si filloi jeta.<\/p>\n

Kjo ide doli nga nj\u00eb vend i papritur. Ju mund t\u00eb mendoni se kjo pjes\u00eb e guximshme e t\u00eb menduarit t\u00eb lir\u00eb do t\u00eb ishte zhvilluar n\u00eb nj\u00eb vend demokratik, me nj\u00eb tradit\u00eb t\u00eb fjal\u00ebs s\u00eb lir\u00eb: ndoshta n\u00eb Shtetet e Bashkuara. Por n\u00eb fakt hipoteza e par\u00eb p\u00ebr origjin\u00ebn e jet\u00ebs u shpik n\u00eb nj\u00eb vend t\u00eb eg\u00ebr totalitar, ku u m\u00ebnjanua mendimi i lir\u00eb: BRSS.<\/p>\n

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\"\"Alexander Oparin jetoi dhe punoi n\u00eb USSR<\/em> (Credit: Sputnik\/Science Photo Library)<\/p>\n<\/blockquote>\n

N\u00eb Rusin\u00eb e Stalinit, gjith\u00e7ka ishte n\u00ebn kontrollin e shtetit. Kjo p\u00ebrfshinte idet\u00eb e njer\u00ebzve, madje edhe n\u00eb tema – si biologjia – q\u00eb duken t\u00eb palidhura me politik\u00ebn komuniste.<\/p>\n

Oparin imagjinonte se \u00e7far\u00eb ishte Toka kur sapo u formua<\/em><\/p><\/blockquote>\n

M\u00eb t\u00eb famshmja, Stalini n\u00eb m\u00ebnyr\u00eb efektive i ndaloi shkenc\u00ebtar\u00ebt t\u00eb studiojn\u00eb gjenetik\u00eb konvencionale. N\u00eb vend t\u00eb k\u00ebsaj ai vuri n\u00eb dukje idet\u00eb<\/a> e nj\u00eb pun\u00ebtori t\u00eb ferm\u00ebs me emrin Trofim Lysenko<\/a>, t\u00eb cilat ai mendonte se ishin m\u00eb n\u00eb p\u00ebrputhje me ideologjin\u00eb komuniste. Shkenc\u00ebtar\u00ebt q\u00eb punojn\u00eb n\u00eb gjenetik\u00eb jan\u00eb t\u00eb detyruar t\u00eb mb\u00ebshtesin publikisht idet\u00eb e Lysenkos, ose rrezikojn\u00eb t\u00eb p\u00ebrfundojn\u00eb n\u00eb nj\u00eb kamp pune.<\/p>\n

Ishte n\u00eb k\u00ebt\u00eb mjedis shtyp\u00ebs ku Aleksand\u00ebr Oparin<\/strong> kreu hulumtimet e tij n\u00eb biokim. Ai ishte n\u00eb gjendje t\u00eb vazhdonte t\u00eb punonte sepse ishte nj\u00eb komunist besnik: ai p\u00ebrkrahu idet\u00eb e Lysenkos dhe madje mori Urdhrin e Leninit, dekorimin m\u00eb t\u00eb lart\u00eb q\u00eb mund t’i jepej dikujt q\u00eb jetonte n\u00eb BRSS.<\/p>\n

N\u00eb vitin 1924, Oparin botoi librin e tij Origjina e Jet\u00ebs<\/a>. N\u00eb t\u00eb ai krijoi nj\u00eb vizion p\u00ebr lindjen e jet\u00ebs q\u00eb ishte shum\u00eb e ngjashme me pellgun e ngroht\u00eb t\u00eb Darvinit.<\/p>\n

\n

\"\"Oqean\u00ebt u krijuan pasi Toka u ftohur<\/em> (Credit: Richard Bizley\/Science Photo Library)<\/p>\n<\/blockquote>\n

Oparin imagjinonte se \u00e7far\u00eb ishte Toka kur sapo u formua. Sip\u00ebrfaqja ishte tep\u00ebr e nxeht\u00eb, nd\u00ebrsa gur\u00ebt nga hap\u00ebsira binin mbi t\u00eb dhe zhyteshin posht\u00eb dhe shkriheshin. Ishte nj\u00eb rr\u00ebmuj\u00eb me shk\u00ebmbinj gjysm\u00eb t\u00eb shkrir\u00eb, q\u00eb p\u00ebrmbante nj\u00eb gam\u00eb t\u00eb madhe t\u00eb kimikateve – duke p\u00ebrfshir\u00eb shum\u00eb elemente me baz\u00eb karboni.<\/p>\n

N\u00ebse ju shikoni coacervates<\/em>1<\/sup>) n\u00ebn nj\u00eb mikroskop, ata sillen si qelizat e gjalla t\u00eb shtangura<\/em><\/strong><\/p>\n

P\u00ebrfundimisht, Toka u ftoh dhe avujt e ujit u ngjesh\u00eb n\u00eb uj\u00eb t\u00eb l\u00ebngsh\u00ebm dhe ra edhe shiu i par\u00eb. Shum\u00eb koh\u00eb para se Toka t\u00eb kishte oqeane, t\u00eb cilat ishin t\u00eb nxehta dhe t\u00eb pasura me kimikate me baz\u00eb karboni. Tani dy gj\u00ebra mund t\u00eb ndodhin.<\/p>\n

S\u00eb pari<\/em>, kimikatet e ndryshme mund t\u00eb reagojn\u00eb me nj\u00ebri-tjetrin p\u00ebr t\u00eb formuar shum\u00eb komponime t\u00eb reja, disa prej t\u00eb cilave do t\u00eb ishin m\u00eb komplekse. Oparin mendonte se molekulat n\u00eb qend\u00ebr t\u00eb jet\u00ebs, si sheqernat dhe aminoacidet, t\u00eb gjitha mund t\u00eb formoheshin n\u00eb uj\u00ebrat e Tok\u00ebs.<\/p>\n

S\u00eb dyti<\/em>, disa nga kimikatet filluan t\u00eb formojn\u00eb struktura mikroskopike. Shum\u00eb kimikate organike nuk treten n\u00eb uj\u00eb: p\u00ebr shembull, vaji formon nj\u00eb shtres\u00eb n\u00eb maj\u00eb t\u00eb ujit. Por, kur disa nga kimikatet kontaktojn\u00eb me uj\u00eb, ato formojn\u00eb globula sferike t\u00eb quajtura “coacervates”, t\u00eb cilat mund t\u00eb jen\u00eb deri n\u00eb 0.01 cm (0.004 in\u00e7).<\/p>\n

N\u00ebse ju shikoni coacervates n\u00ebn nj\u00eb mikroskop, ata sillen si qelizat e gjalla t\u00eb shtangura. Ata rriten dhe ndryshojn\u00eb form\u00ebn, dhe nganj\u00ebher\u00eb ndahen n\u00eb dy. Ata gjithashtu mund t\u00eb marrin kimikate nga uji p\u00ebrreth, k\u00ebshtu q\u00eb kimikatet e ngjashme me jet\u00ebn mund t\u00eb p\u00ebrqendrohen brenda tyre. Oparin propozoi q\u00eb coacervates ishin paraardh\u00ebsit e qelizave moderne.<\/p>\n

Ideja q\u00eb organizmat e gjall\u00eb mund t\u00eb formohen nga mjete t\u00eb thjeshta kimike, pa nj\u00eb zot apo edhe nj\u00eb “forc\u00eb t\u00eb jet\u00eb”, ishin radikale<\/em><\/p><\/blockquote>\n

Pes\u00eb vjet m\u00eb von\u00eb n\u00eb vitin 1929, biologu anglez J. B. S. Haldane<\/strong> propozoi n\u00eb m\u00ebnyr\u00eb t\u00eb pavarur disa ide shum\u00eb t\u00eb ngjashme n\u00eb nj\u00eb artikull t\u00eb shkurt\u00ebr<\/a> t\u00eb botuar n\u00eb Vjetor\u00ebn Racionaliste<\/a>.<\/p>\n

Haldani kishte b\u00ebr\u00eb tashm\u00eb nj\u00eb kontribut t\u00eb jasht\u00ebzakonsh\u00ebm n\u00eb teorin\u00eb e evolucionit, duke ndihmuar n\u00eb integrimin e ideve t\u00eb Darvinit me shkenc\u00ebn n\u00eb zhvillim t\u00eb gjenetik\u00ebs.<\/p>\n

Ai ishte gjithashtu nj\u00eb karakter m\u00eb i madh se vet\u00eb jeta. N\u00eb nj\u00eb rast, ai p\u00ebsoi nj\u00eb shpim t\u00eb daulles s\u00eb veshit, p\u00ebr shkak t\u00eb disa eksperimenteve me dhomat e dekompresionit, por m\u00eb von\u00eb ai shkruante se: “daullet n\u00eb p\u00ebrgjith\u00ebsi sh\u00ebrohen, dhe n\u00ebse ka nj\u00eb vrim\u00eb n\u00eb t\u00eb, ndon\u00ebse \u00ebsht\u00eb disi i shurdh\u00ebr, dikush mund t\u00eb nxjerr\u00eb tym duhani nga veshi n\u00eb fjal\u00eb, gj\u00eb q\u00eb \u00ebsht\u00eb nj\u00eb arritje sociale<\/em>“.<\/p>\n

Ashtu si Oparin, Haldane p\u00ebrshkroi se si kimikatet organike mund t\u00eb nd\u00ebrtohen n\u00eb uj\u00eb, “[deri sa] oqeanet primitive arrit\u00ebn konsistenc\u00ebn e sup\u00ebs s\u00eb nxeht\u00eb t\u00eb holluar<\/em>“. Kjo krijoi sken\u00ebn p\u00ebr “formimin e gj\u00ebrave t\u00eb para t\u00eb gjalla ose gjysm\u00eb t\u00eb gjalla<\/em>” dhe p\u00ebr secil\u00ebn prej tyre t\u00eb mbyllet n\u00eb “nj\u00eb film me vaj<\/em>“.<\/p>\n

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\"\"Gjenetisti anglez J. B. S. Haldane<\/em> (Credit: Science Photo Library)<\/p>\n<\/blockquote>\n

Thuhet se nga t\u00eb gjith\u00eb biolog\u00ebt n\u00eb bot\u00eb, Oparin<\/strong> dhe Haldane<\/strong> e propozuan k\u00ebt\u00eb hipotez\u00eb. Ideja q\u00eb organizmat e gjall\u00eb t\u00eb formuara nga mjete thjesht kimike, pa nj\u00eb zot apo edhe nj\u00eb “forc\u00eb jete”, ishin radikale. Ashtu si teoria e evolucionit t\u00eb Darvinit p\u00ebrpara k\u00ebsaj, kjo e goditi n\u00eb fytyr\u00eb krishterimin.<\/p>\n

Kishte nj\u00eb problem. Nuk kishte ende d\u00ebshmi eksperimentale p\u00ebr ta mb\u00ebshtetur at\u00eb<\/em><\/p><\/blockquote>\n

Kjo i p\u00ebrshtatej BRSS-s\u00eb mjaft mir\u00eb. Regjimi sovjetik ishte zyrtarisht ateist dhe lider\u00ebt e saj ishin t\u00eb etur p\u00ebr t\u00eb mb\u00ebshtetur shpjegime materialiste p\u00ebr fenomenet e thella si jeta. Haldani ishte gjithashtu nj\u00eb ateist dhe nj\u00eb komunist i p\u00ebrkushtuar si fillim.<\/p>\n

“N\u00eb at\u00eb koh\u00eb, p\u00ebr t\u00eb pranuar ose jo k\u00ebt\u00eb ide, varej kryesisht nga personalitetet: qofshin ato fetare ose qofshin ata q\u00eb mb\u00ebshtesnin idet\u00eb e majt\u00eb apo komuniste<\/em>“, thot\u00eb eksperti i origjin\u00ebs Armen Mulkidjanian<\/a> i Universitetit t\u00eb Osnabr\u00fcck n\u00eb Gjermani. “N\u00eb Bashkimin Sovjetik, ata u prit\u00ebn me k\u00ebnaq\u00ebsi, sepse nuk kishin nevoj\u00eb p\u00ebr Per\u00ebndin\u00eb. N\u00eb bot\u00ebn per\u00ebndimore, n\u00ebse do t\u00eb shikoni p\u00ebr njer\u00ebzit q\u00eb mendonin n\u00eb k\u00ebt\u00eb drejtim, t\u00eb gjith\u00eb ishin t\u00eb majt\u00eb, komunist\u00eb e k\u00ebshtu me radh\u00eb<\/em>“.<\/p>\n

Ideja q\u00eb jeta \u00ebsht\u00eb formuar n\u00eb nj\u00eb sup\u00eb primordiale t\u00eb kimikateve organike u b\u00eb e njohur si hipoteza Oparin-Haldane<\/strong>. Ishte e past\u00ebr dhe bind\u00ebse, por kishte nj\u00eb problem. Nuk kishte d\u00ebshmi eksperimentale p\u00ebr ta mb\u00ebshtetur at\u00eb<\/strong>. Kjo nuk do t\u00eb arrij\u00eb pothuajse nj\u00eb \u00e7erek shekulli.<\/p>\n

\n

\"\"Harold Urey<\/em>
\n(Credit: Emilio Segre Visual Archives\/American Institute of Physics\/Science Photo Library)<\/p>\n<\/blockquote>\n

N\u00eb koh\u00ebn kur Harold Urey<\/strong><\/a> u interesua p\u00ebr origjin\u00ebn e jet\u00ebs, ai tashm\u00eb kishte fituar \u00e7mimin Nobel t\u00eb Kimis\u00eb<\/a> n\u00eb vitin 1934 dhe ndihmoi n\u00eb nd\u00ebrtimin e bomb\u00ebs atomike. Gjat\u00eb Luft\u00ebs s\u00eb Dyt\u00eb Bot\u00ebrore, Urey punoi n\u00eb Projektin Manhattan, duke mbledhur uraniumin e paq\u00ebndruesh\u00ebm 235 t\u00eb nevojsh\u00ebm p\u00ebr thelbin e bomb\u00ebs. Pas luft\u00ebs ai luftoi p\u00ebr t\u00eb mbajtur teknologjin\u00eb b\u00ebrthamore n\u00ebn kontroll civil.<\/p>\n

N\u00eb vitin 1952, Milleri filloi eksperimentin m\u00eb t\u00eb famsh\u00ebm mbi origjin\u00ebn e jet\u00ebs, q\u00eb u p\u00ebrpoq ndonj\u00ebher\u00eb<\/em><\/p><\/blockquote>\n

Ai gjithashtu u interesua p\u00ebr kimin\u00eb e hap\u00ebsir\u00ebs s\u00eb jashtme, ve\u00e7an\u00ebrisht at\u00eb q\u00eb vazhdoi kur sistemi diellor po formohej. Nj\u00eb dit\u00eb ai dha nj\u00eb leksion dhe vuri n\u00eb dukje se ndoshta nuk kishte oksigjen n\u00eb atmosfer\u00ebn e Tok\u00ebs kur u formua s\u00eb pari. Kjo do t\u00eb kishte ofruar kushte ideale p\u00ebr t\u00eb formuar sup\u00eb primare t\u00eb Oparin dhe Haldane: kimikatet e brishta do t\u00eb ishin shkat\u00ebrruar nga kontakti me oksigjenin.<\/p>\n

Nj\u00eb student i doktoratur\u00ebs me emrin Stanley Miller<\/strong> ishte n\u00eb audienc\u00eb dhe m\u00eb von\u00eb iu afrua Urey me nj\u00eb propozim: a mund ta provonin ata k\u00ebt\u00eb ide? Urey ishte skeptik, por Milleri e bindi at\u00eb t\u00eb merrej me k\u00ebt\u00eb.<\/p>\n

Pra, n\u00eb vitin 1952, Milleri filloi eksperimentin m\u00eb t\u00eb famsh\u00ebm mbi origjin\u00ebn e jet\u00ebs q\u00eb u p\u00ebrpoq ndonj\u00ebher\u00eb.<\/p>\n

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\"\"Eksperimenti Miller-Urey<\/em> (Credit: Francis Leroy, Biocosmos\/Science Photo Library)<\/p>\n<\/blockquote>\n

Vendosja ishte e thjesht\u00eb. Milleri lidhi nj\u00eb seri flakash qelqi dhe qarkullonte kat\u00ebr kimikate, q\u00eb ai dyshonte se ishin t\u00eb pranish\u00ebm n\u00eb Tok\u00ebn e hershme: uj\u00eb t\u00eb val\u00eb, gaz hidrogjeni, amoniak dhe metan. Ai i n\u00ebnshtroi gazrat ndaj goditjeve t\u00eb p\u00ebrs\u00ebritura elektrike, p\u00ebr t\u00eb simuluar sulmet e rrufes\u00eb, q\u00eb do t\u00eb kishin qen\u00eb nj\u00eb dukuri e zakonshme n\u00eb Tok\u00eb shum\u00eb koh\u00eb m\u00eb par\u00eb.<\/p>\n

Ju mund t\u00eb shkoni n\u00eb nj\u00eb atmosfer\u00eb t\u00eb thjesht\u00eb dhe t\u00eb prodhoni shum\u00eb molekula biologjike<\/em><\/p><\/blockquote>\n

Miller gjeti se “uji n\u00eb balon\u00eb u b\u00eb duksh\u00ebm tr\u00ebndafili pas dit\u00ebs s\u00eb par\u00eb dhe deri n\u00eb fund t\u00eb jav\u00ebs zgjidhja ishte e kuqe e thell\u00eb dhe e turbullt<\/em>“. \u00cbsht\u00eb e qart\u00eb q\u00eb \u00ebsht\u00eb formuar nj\u00eb p\u00ebrzierje e kimikateve.<\/p>\n

Kur Miller analizoi p\u00ebrzierjen ai gjeti se p\u00ebrmbante dy aminoacide: glycine<\/strong> dhe alanine<\/strong>. Aminoacidet shpesh p\u00ebrshkruhen si blloqet e nd\u00ebrtimit t\u00eb jet\u00ebs. Ato p\u00ebrdoren p\u00ebr t\u00eb formuar proteinat, q\u00eb kontrollojn\u00eb shumic\u00ebn e proceseve biokimike n\u00eb trupin ton\u00eb. Milleri kishte b\u00ebr\u00eb dy nga komponent\u00ebt m\u00eb t\u00eb r\u00ebnd\u00ebsish\u00ebm t\u00eb jet\u00ebs, nga e para.<\/p>\n

Rezultatet u publikuan n\u00eb revist\u00ebn prestigjioze Science n\u00eb vitin 1953<\/a>. Urey, n\u00eb nj\u00eb veprim vet\u00ebmohues t\u00eb pazakont\u00eb midis shkenc\u00ebtar\u00ebve t\u00eb vjet\u00ebr, e mori emrin e tij nga letra, duke i dh\u00ebn\u00eb kredi vet\u00ebm Miller p\u00ebr eksperimentin e arritjet. P\u00ebrkund\u00ebr k\u00ebsaj, studimi njihet shpesh si “Eksperimenti Miller-Urey<\/a>“.<\/p>\n

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\"\"Stanley Miller n\u00eb laboratorin e tij<\/em> (Credit: Science Photo Library)<\/p>\n<\/blockquote>\n

“Forca e Miller-Urey \u00ebsht\u00eb t\u00eb tregoj\u00eb se mund t\u00eb shkosh nga nj\u00eb atmosfer\u00eb e thjesht\u00eb dhe t\u00eb prodhosh shum\u00eb molekula biologjike<\/em>“, thot\u00eb John Sutherland<\/a> i Laboratorit t\u00eb Biologjis\u00eb Molekulare n\u00eb Kembrixh t\u00eb Britanis\u00eb s\u00eb Madhe.<\/p>\n

Jeta qenka m\u00eb e nd\u00ebrlikuar, se \u00e7’ishte menduar<\/em><\/strong><\/p>\n

Detajet treguan se ishin t\u00eb gabuara, pasi studimet e m\u00ebvonshme treguan se atmosfera e hershme e Tok\u00ebs kishte nj\u00eb p\u00ebrzierje t\u00eb ndryshme t\u00eb gazrave. Por kjo \u00ebsht\u00eb pothuajse pran\u00eb pik\u00ebs n\u00eb fjal\u00eb.<\/p>\n

“Ishte nj\u00eb masivizim ikonik, stimuloi imagjinat\u00ebn e publikut dhe vazhdon t\u00eb p\u00ebrmendet gjer\u00ebsisht<\/em>“, thot\u00eb Sutherland.<\/p>\n

Pas eksperimentit t\u00eb Millerit, shkenc\u00ebtar\u00eb t\u00eb tjer\u00eb filluan t\u00eb gjejn\u00eb m\u00ebnyra p\u00ebr t\u00eb b\u00ebr\u00eb molekula t\u00eb thjeshta biologjike nga e para. Nj\u00eb zgjidhje p\u00ebr misterin e origjin\u00ebs s\u00eb jet\u00ebs dukej e af\u00ebrt.<\/p>\n

Por m\u00eb pas u b\u00eb e qart\u00eb se jeta ishte m\u00eb e komplikuar sesa mendonte dikush. Qelizat e gjalla, doli, nuk ishin vet\u00ebm \u00e7anta me kimikate: ata ishin makina t\u00eb nd\u00ebrlikuara. Papritmas, duke e b\u00ebr\u00eb nj\u00eb nga e para, filluan t\u00eb duken si nj\u00eb sfid\u00eb shum\u00eb m\u00eb e madhe, sesa shkenc\u00ebtar\u00ebt e kishin parashikuar.<\/p>\n

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\"\"Makineria brenda qelizave \u00ebsht\u00eb e pabesueshme dhe intriguese<\/em>
\n(Credit: Equinox Graphics Ltd)<\/p>\n<\/blockquote>\n

Kapitulli 2. Polarizimi i madh<\/strong><\/p>\n

Nga fillim t\u00eb viteve 1950, shkenc\u00ebtar\u00ebt ishin larguar nga supozimi i gjat\u00eb, q\u00eb jeta ishte nj\u00eb dhurat\u00eb nga per\u00ebndit\u00eb. Ata kishin filluar t\u00eb shqyrtonin mund\u00ebsin\u00eb q\u00eb jeta t\u00eb formohej spontanisht dhe natyrsh\u00ebm n\u00eb Tok\u00ebn e hershme – dhe fal\u00eb eksperimentit ikonik t\u00eb Stanley Miller, ata madje kishin nj\u00eb mb\u00ebshtetje praktike p\u00ebr k\u00ebt\u00eb ide.<\/p>\n

Nd\u00ebrsa Miller po p\u00ebrpiqej t\u00eb b\u00ebnte gj\u00ebrat e jet\u00ebs nga e para, shkenc\u00ebtar\u00eb t\u00eb tjer\u00eb po kuptonin se nga cilat gjene ishim b\u00ebr\u00eb.<\/p>\n

Deri n\u00eb k\u00ebt\u00eb koh\u00eb, shum\u00eb molekula biologjike ishin t\u00eb njohura. K\u00ebto p\u00ebrfshinin sheqer, yndyrna, proteina – dhe acide nukleike t\u00eb tilla si “acid deoxyribonucleic<\/em>“, ose ADN<\/strong> p\u00ebr ta shkurt\u00ebr.<\/p>\n

Ata b\u00ebn\u00eb nj\u00eb nga zbulimet m\u00eb t\u00eb m\u00ebdha shkencore t\u00eb shekullit t\u00eb 20-t\u00eb<\/em><\/p><\/blockquote>\n

Sot ne e marrim si t\u00eb mir\u00ebqen\u00eb se ADN-ja mbart gjenet tona, por kjo n\u00eb fakt erdhi si nj\u00eb tronditje p\u00ebr biolog\u00ebt e viteve 1950. Proteinat jan\u00eb m\u00eb komplekse, k\u00ebshtu q\u00eb shkenc\u00ebtar\u00ebt mendonin se ishin gjenet.<\/p>\n

Kjo ide u hodh posht\u00eb n\u00eb vitin 1952 nga Alfred Hershey<\/strong> dhe Martha Chase<\/strong> nga Institucioni Carnegie i Uashingtonit. Ata studiuan viruse t\u00eb thjeshta q\u00eb p\u00ebrmbajn\u00eb vet\u00ebm ADN dhe proteina dhe t\u00eb cilat duhet t\u00eb infektojn\u00eb bakteret n\u00eb m\u00ebnyr\u00eb q\u00eb t\u00eb riprodhohen. Ata gjet\u00ebn se ishte ADN virale, q\u00eb hyri n\u00eb baktere: proteinat q\u00ebndruan jasht\u00eb<\/a>. \u00cbsht\u00eb e qart\u00eb se ADN-ja ishte materiali gjenetik<\/strong>.<\/p>\n

Rezultatet e Hershey dhe Chase shkaktuan nj\u00eb gar\u00eb t\u00eb furish\u00ebm p\u00ebr t\u00eb zbuluar struktur\u00ebn e ADN-s\u00eb, dhe k\u00ebshtu shkoi kjo pun\u00eb. Nj\u00eb vit m\u00eb pas, problemi u plasua nga Francis Crick<\/strong><\/a> dhe James Watson<\/strong><\/a> nga Universiteti i Kembrixhit, n\u00eb Mbret\u00ebrin\u00eb e Bashkuar – me shum\u00eb ndihm\u00eb t\u00eb n\u00ebnvler\u00ebsuar nga kolegu i tyre Rosalind Franklin<\/strong><\/a>.<\/p>\n

Kjo ishte nj\u00eb nga zbulimet m\u00eb t\u00eb m\u00ebdha shkencore t\u00eb shekullit t\u00eb 20-t\u00eb. Ai gjithashtu e ridrejtoi k\u00ebrkimin p\u00ebr origjin\u00ebn e jet\u00ebs, duke zbuluar ngat\u00ebrres\u00ebn e pabesueshme q\u00eb \u00ebsht\u00eb e fshehur brenda qelizave t\u00eb gjalla.<\/p>\n

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\"\"James Watson dhe Francis Crick me modelin e tyre t\u00eb ADN-s\u00eb<\/em>
\n(Credit: A. Barrington-Brown\/Gonville and Caius College\/Science Photo Library)<\/p>\n<\/blockquote>\n

Crick dhe Watson kuptuan se ADN \u00ebsht\u00eb nj\u00eb spirale e dyfisht\u00eb, si nj\u00eb shkall\u00eb q\u00eb \u00ebsht\u00eb shtremb\u00ebruar n\u00eb spirale. T\u00eb dy “shtyllat” e shkall\u00ebs jan\u00eb nd\u00ebrtuar secila prej molekulave t\u00eb quajtura nukleotide.<\/p>\n

Gjenet tuaja vijn\u00eb n\u00eb fund t\u00eb fundit nga nj\u00eb bakter st\u00ebrgjyshor<\/em><\/p><\/blockquote>\n

Kjo struktur\u00eb shpjegoi se si qelizat kopjojn\u00eb ADN-n\u00eb e tyre. Me fjal\u00eb t\u00eb tjera, zbuloi se si prind\u00ebrit b\u00ebjn\u00eb kopje t\u00eb gjeneve t\u00eb tyre dhe i kalojn\u00eb ato tek f\u00ebmij\u00ebt e tyre.<\/p>\n

\u00c7\u00ebshtja ky\u00e7e \u00ebsht\u00eb se spiralja e dyfisht\u00eb mund t\u00eb “hiqet”. Kjo ekspozon kodin gjenetik – i p\u00ebrb\u00ebr\u00eb nga sekuenca t\u00eb bazave gjenetike A (adenin\u00eb), T (timin\u00eb), C (citozin\u00eb) dhe G (guanin\u00eb) – q\u00eb normalisht mbyllen brenda “rungs” (k\u00ebmb\u00eb shkalle) t\u00eb shkall\u00ebve t\u00eb ADN-s\u00eb. \u00c7do varg p\u00ebrdoret pastaj si nj\u00eb shabllon p\u00ebr t\u00eb rikrijuar nj\u00eb kopje t\u00eb tjetr\u00ebs.<\/p>\n

Duke p\u00ebrdorur k\u00ebt\u00eb mekaniz\u00ebm, gjenet jan\u00eb kaluar nga prind\u00ebrit te f\u00ebmij\u00ebt, q\u00eb nga fillimi i jet\u00ebs. Gjenet tuaja vijn\u00eb n\u00eb fund t\u00eb fundit nga nj\u00eb bakter st\u00ebrgjyshor – dhe n\u00eb \u00e7do hap ata u kopjuan duke p\u00ebrdorur mekanizmin, q\u00eb Crick dhe Watson zbuluan.<\/p>\n

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