Masana juyin halitta: matakai da ainihin

A yayin gyaran kimiyyar kimiyya, abin da ake kira sinadaran juyin halitta ya faru, kuma juyin juyawar wannan juyin juya hali ya kasance bayan halittar a 1777 na masanin kimiyya na Faransa Lavoisier ka'idar combustion tare da bayanin irin aikin oxygen. A lokaci guda, sake duba dukkanin manufofi na ainihi da kuma ka'idodin ilmin sunadarai sun fara, kalmomi da nomenclature na abubuwa sun canza.

Aikin farko

A shekara ta 1789 ya sami lakabin littafin Lavoisier, nan da nan ya zama babban kayan aiki ga masu ilimin likitanci da masu aiki na kimiyyar haifa. A cikin "Matakan ilimin sunadarai" ya riga ya zama na farko a jerin duniya - tebur na jiki mai sauƙi, wanda ya lissafa abubuwan da aka sani sunadarai. A cikin wannan rukuni na Lavoisier sa ka'idodin hadisin oxygen, ta hanyar da aka tsara juyin halittar sinadaran ta hanyar sabuwar hanya. A mafi muhimmanci kashi a cikin definition of - kwarewa, wanda shi ne abin da masanin kimiyya da zabe da babban rarrabẽwa, da kuma duk abin da aka ba tabbatar da kwarewa, kamar wani atomic ko kwayoyin tsarin, Lavoisier ba a gani.

Masana juyin halitta ya tafi da dokokin da aka tsara ta - game da adana masallacin, yanayin dabi'un mahalli, da bambance-bambance a cikin maɓallin haɓaka. A halin yanzu ilimin kimiyya ya ɗauki nau'i na kimiyya a matsayin mai zaman kansa, yana nazari akan jigilar jikin ta hanyar gwaji. Masana juyin halitta ba zai iya yin ba tare da yin tunanin abin ba, don haka, 'yan adam sun watsar da abubuwan da suka gabata, saboda ra'ayoyin game da yanayin kwayoyin halitta da dukiyoyi sun canza saurin da sauri. Kuma damuwa ga wannan tsari shine bincike na Lavoisier. Yanzu, ko da makaranta san cewa matakai na juyin halittar sunadarai (ko prebiotic juyin halitta) kamata a yi la'akari tun daga lokacin da ba wadda ta gabãta na rayuwa aban kasa. A karni na goma sha takwas, babu wanda yake da irin waɗannan ra'ayoyi game da duniya duk da haka.

Rayuwa

Masanan sunadarai na duniya ya fara ne a duniya wanda ba shi da rai, lokacin da kwayoyin kwayoyin sun fara fitowa daga kwayoyin halitta, wanda aka rinjayi ta hanyar musamman ta hanyar makamashi da zaɓuɓɓuka. Ayyukan kungiyoyi masu zaman kansu wadanda ke da halayyar ko da ma tsarin da ke tattare da rikice-rikice sun bayyana. Saboda haka, a duniya akwai carbon. Maimakon haka, sunadarai masu dauke da kwayar halitta sun fara bayyana, wadanda basu da mahimmancin muhimmancin ba kawai don fitowarwa ba, amma har ma don ci gaba da bunkasa kowane abu mai rai.

Har yanzu ba mu san abinda ainihin juyin halitta yake ba a farkon farkon rayuwa. Sanin ilimin sunadarai na kowane abu ya rage ka'idar juyin halitta zuwa iyakoki na isikun ruwa-carbon. Zai yiwu, a cikin sararin samaniya akwai zabin sauran yanayin na zama na rai al'amari , kuma asalin mu gina jiki - ba kawai "hanyar fita". A nan, haɗakarwa ta musamman na halayyar carbon polymerization tare da haɓakar ƙaƙƙarfan haɓakaccen magungunan ruwa a cikin yanayin ruwa ya cika. Wadannan ka'idodi sun isa don fara juyin halittar sinadaran rai, kuma ya zama dole don ci gaba da dukkan nau'ukan rayuwa da aka sani a gare mu.

Fara tsari

Mutane sun san ko da komai game da ɗakin jariri. Musamman game da inda kuma lokacin da matakan sinadarin sunadarai a duniya suka fara. Za mu iya ɗauka kawai. A nan, a farkon, cikakken lokaci yana yiwuwa.

Idan ka gama na biyu sake zagayowar na star samuwar lokacin da takaice kayayyakin da fashewa daga supernovas, wanda ya ba da interstellar sarari abubuwa kira nauyi, wanda nauyi ya wuce ashirin da shida. Lokacin da taurarin da suka riga sun kasance a cikin ƙarni na biyu sun sami tsarin kansu na duniya, inda manyan abubuwa masu nauyi sun riga sun isa. Tashin gaskiyar juyin halitta zai iya faruwa a kowane lokaci bayan Big Bang a cikin tazara daga rabin biliyan zuwa shekaru biliyan daya da rabi.

Inda aka haifa rayuwa

Inda za ta iya samo asali ne kuma tambaya ce. Lokacin da aka samar da yanayi mai yawa, yiwuwar kaddamar da ilimin sinadarai zai iya faruwa a kusan kowane yanayi. Wannan shine zurfin sararin samaniya, da zurfin teku, da farfajiyar, har ma da hanyoyin da ake amfani da su.

Bugu da ƙari, gizagizai na iskar gas zai iya kasancewa a matsayin maɓuɓɓugar ruwa don tayar da kwayoyin halittu akan rashin rayuwa, kuma abubuwan da aka gano a ciki sun tabbatar da su - maye gurbi da sugars, aldehydes, amino acid na glycine da sauransu, wanda zai iya zama abin farawa don bayyanar rayuwa ta hanyar juyin halittar sinadaran da ya fara.

Ka'idar

Tsohuwar Duniya tana riƙe asirinta, kuma mutum bai riga ya sami bayani mai dadi akan yanayin yanayin geochemical da kasancewarsa ba kafin bayyanuwar rayuwa. Nazarin binciken ilimin lissafi ba zai iya cika dukkan batutuwa masu tasowa ba, sabili da haka astronomy ana amfani dashi don binciken. Saboda haka an gina ka'idar juyin halittar sinadaran. Yanayin Venus ko zamanin Martian yau ana daukar su ne daidai da duniya a wasu matakai na juyin halitta.

An gabatar da gwaje-gwajen a kan samfurori, kuma haka dukkanin bayanan da aka sani da mu an samu. Alal misali, ta hanyar kirkiro wasu nau'o'in sunadarai masu yawa da yanayin yanayi a cikin yanayi, an samar da ruwa, lithosphere, kwayoyin kwayoyin halitta. Samun sababbin bayanai ta hanyar gwaji yana nufin wadatar da ka'idar a yau da kullum. Saboda haka, akwai abubuwa da yawa game da wasu hanyoyi da kuma wasu motsin kai tsaye na juyin halittar sinadaran da ya faru.

Bincike a Rasha

Rayuwa a duniya ta samo asali ne saboda abiogenesis, wato, haihuwar mahadiyar halittu waɗanda wanzuwar su ke kasancewa cikin yanayin rayuwa a waje da wani kwayoyin halitta kuma ba tare da sanya hannu ba. Wannan shine mataki na farko lokacin da mai rai ya bayyana daga marasa rai.

Bisa ga zaton Masanin Academician Oparin a cikin ashirin na karni na ashirin, mafita na magungunan kwayoyin halitta sun iya samar da wasu yankuna inda ake karuwarsu a hankali, kuma rabuwa daga yanayin waje baya hana su yin musayar tare da shi. Wadannan yankuna suna kira coacervates ko coacervate saukad da.

Ƙasar

An fara kira na farko abiogenic, wanda aka gudanar a ƙarƙashin yanayin duniya ta farko, a shekara ta 1953 da Stanley Miller yayi, tare da hada kwayoyin amino acid tare da sauran kwayoyin halitta. Daga bisani, ka'idar tsararraki ta bayyana, wanda ke bayyana bayyanar rayuwa ta hanyar juyin halitta ta sinadaran ta wurin kasancewar kamfanoni na halayen halayyar haɓaka wanda suka biyo bayan juna, inda samfurin wanda ya gabata ya zama mai haɓakawa na gaba.

Sai kawai a shekarar 2008, masana ilimin halitta na Amurka sun halicci "ladabi" na farko, wanda ta hanyar membrane na fatty acid da lipids ya sami damar samun mahallin halittu daga yanayin. Wadannan "tubalin" da ake aiki da su a cikin jiki suna da muhimmanci sosai ga DNA kira. Kuma a shekarar 2011 a Japan, an halicci kwayoyin halitta tare da abubuwa na DNA a ƙarƙashin harsashin cationic, waɗanda suka iya rarraba, tun da akwai wani nau'i mai nau'in poly-dimensional wanda yayi maimaita DNA.

Muhimman abubuwa

Halittar sinadaran rayuwa a duniya a cikin kwakwalwa ya bayyana abubuwan da ke biyo baya.

1. Bukatar bayyanar a duniya ko a cikin Cosmos na yanayin da ake amfani da kwayoyin halitta na kwayoyin halittu, da kuma kira da yawa da yawa da yawa don isa ga tsarin juyin halitta.
2. Ana fitowa daga tsarin kwayoyin halitta wanda ya fito daga kwayoyin da aka bayyana a sama. Wadannan sanannun barga sun ƙauracewa daga yanayi, ƙarfin hali da kuma wadata a cikin su sun wuce. Don haka akwai tsarin tsarin salon salula.
3. A sakamakon haka, akwai damar samun cigaba mai zaman kanta - sabunta kai da sauyawar dukkan tsarin tsarin sinadaran bayanai. Don haka akwai rassa na farko na lambar sirri.
4. Mataki na gaba shine bayyanar tsinkayar tsakanin ayyukan enzyme da kuma dukiyar sunadarai tare da RNA da DNA a matsayin mai ba da bayanai. Saboda haka, lambar sirri da kanta, wadda take da muhimmanci ga juyin halittar halitta, taso.

Bincike

Kamar yadda aka fada a sama, Oparin ya bude koyawa a cikin shekaru ashirin na karni na karshe. Karin Stanley Miller da Harold Urey a shekara ta 1953 sun bayyana abin da ya faru a cikin jigilar yanayi mai sauƙi na kwayoyin halitta da kuma yadda suke faruwa. Daga baya, Sydney Fox ya gaya wa duniya game da microspheres na maganin. A 1981, T. Cecu da S. Altman sun yi nasara wajen lura da ragowar RNA, wanda yake iya hada bayanai da catalysis a cikin kwayoyin, "yanke" kansu daga sarkar kuma suna haɗa sauran "iyakar".

A shekara ta 1986, W. Gilbert na Cambridge ya ci gaba da ra'ayin "Duniya na RNA", yayin da Günter von Kidrowski daga Jamus ya gabatar da tsarin tsarin DNA na farko, wanda shine babbar gudummawar fahimtar tsarin tsarin kai da kuma ayyukan ci gaban su. Kimiyya ta cigaba da sauri a cikin wannan hanya: Manfred Eigen ya gano maɓalli, juyin halitta na haɗin kwayoyin RNA, kuma Julius Rebecque ya kirkiro na farko da kwayar halitta wanda ke yin amfani da shi a cikin chloroform.

Space da Duniya

A NASA's Space Flight Center, John Corlis ya yi nazari game da samar da makamashi da sunadarai daga maɓuɓɓugar ruwan zafi na teku, wanda ke haifar da juyin halittar sinadaran daga yanayin yanayi, kuma a yau suna kasancewa ga archeobacteria na ainihi mazaunin dindindin. A cikin duniya na baƙin ƙarfe sulfides, yawancin jigon gungun Gunther Wachtershauser ya bayyana.

Ya bayyana fasali na farko da aka sake yin amfani da shi tare da musayar abubuwa da suka fito a kan pyrite (iron sulphide), wanda ya ba da makamashi da ake bukata don maganin metabolism. A ƙarƙashin yanayi na zaɓi, girma da ɓaɓɓuka na lu'ulu'u na pyrite na iya girma da ninka, haifar da mutane daban-daban. An kirkiro ma'adanai da aka yi amfani da shi don nuna bayyanar kwayoyin halitta. Duk da haka, ba a wanzuwar samfurin tsarin juyin halitta ba tukuna, tun da tushen ka'idoji na wannan tsari ba a bude ba tukuna.