Lub zog metabolism, uas tshwm sim hauv txhua lub hlwb ntawm lub cev muaj sia, hu ua dissimilation. Nws yog ib txheej ntawm decomposition tshwm sim ntawm cov organic tebchaw, nyob rau hauv uas ib tug npaum li cas ntawm lub zog tso tawm.
Dissimilation tshwm sim nyob rau hauv ob lossis peb theem, nyob ntawm seb hom kab mob nyob. Yog li, nyob rau hauv aerobes, lub zog metabolism muaj xws li kev npaj, tsis muaj oxygen thiab qib oxygen. Hauv anaerobes (cov kab mob uas muaj peev xwm ua haujlwm hauv ib puag ncig anoxic), dissimilation tsis tas yuav tsum tau kauj ruam kawg.
theem kawg ntawm lub zog metabolism hauv aerobes xaus nrog oxidation tiav. Hauv qhov no, kev tawg ntawm cov piam thaj molecules tshwm sim nrog kev tsim lub zog, uas ib feem mus rau kev tsim ntawm ATP.
Nws tsim nyog sau cia tias ATP synthesis tshwm sim hauv cov txheej txheem ntawm phosphorylation, thaum inorganic phosphate ntxiv rau ADP. Nyob rau tib lub sijhawm, adenosine triphosphoric acid yog synthesized hauv mitochondria nrog kev koom tes ntawm ATP synthase.
Cov tshuaj tiv thaiv dab tsi tshwm sim thaum lub zog sib xyaw no tsim?
Adenosine diphosphate thiab phosphate ua ke los ua ATP thiab daim ntawv cog lus macroergic, qhov tsim ntawm yuav siv li 30.6 kJ /mol. Adenosine triphosphate muab cov hlwb nrog lub zog, txij li qhov tseem ceeb ntawm nws tau tso tawm thaum lub sij hawm hydrolysis ntawm cov macroergic bonds ntawm ATP.
Lub tshuab molecular lub luag haujlwm rau kev sib txuas ntawm ATP yog ib qho tshwj xeeb synthase. Nws muaj ob ntu. Ib tug ntawm lawv yog nyob rau hauv daim nyias nyias thiab yog ib tug channel uas protons nkag mus rau hauv lub mitochondria. Qhov no tso tawm lub zog, uas yog ntes los ntawm lwm yam qauv ntawm ATP hu ua F1. Nws muaj ib tug stator thiab rotor. Lub stator nyob rau hauv daim nyias nyias yog tsau thiab muaj ib cheeb tsam delta, nrog rau alpha thiab beta subunits, uas yog lub luag hauj lwm rau cov tshuaj synthesis ntawm ATP. Lub rotor muaj gamma thiab epsilon subunits. Qhov no siv lub zog ntawm protons. Qhov no synthase ua kom cov synthesis ntawm ATP yog hais tias cov protons los ntawm lub txheej membrane raug coj mus rau nruab nrab ntawm lub mitochondria.
Nws yuav tsum tau muab sau tseg tias tshuaj lom neeg cov tshuaj tiv thaiv nyob rau hauv lub cell yog characterized los ntawm spatial kev txiav txim. Cov khoom lag luam ntawm cov tshuaj sib cuam tshuam ntawm cov khoom raug faib tawm asymmetrically (zoo ions ions mus rau hauv ib qho kev coj, thiab cov khoom tsis zoo mus rau lwm qhov), tsim kom muaj peev xwm ntawm electrochemical ntawm daim nyias nyias. Nws muaj cov tshuaj lom neeg thiab cov khoom siv hluav taws xob. Nws yuav tsum tau hais tias nws yog qhov muaj peev xwm ntawm qhov chaw ntawm mitochondria uas dhau los ua lub ntiaj teb daim ntawv ntawm lub zog cia.
Tus qauv no tau tshawb pom los ntawm tus kws tshawb fawb Askiv P. Mitchell. Nws qhiaCov tshuaj tom qab oxidation tsis zoo li cov molecules, tab sis qhov zoo thiab tsis zoo them ions, uas nyob rau sab nraud ntawm mitochondrial membrane. Qhov kev xav no ua rau nws muaj peev xwm hais txog qhov tsim ntawm macroergic bonds ntawm phosphates thaum lub sij hawm kev sib txuas ntawm adenosine triphosphate, nrog rau tsim cov chemiosmotic hypothesis ntawm cov tshuaj tiv thaiv no.
