Photosynthesis hloov zuj zus los ntawm 3 billion xyoo dhau los thiab tso oxygen rau hauv qhov chaw. Cellular respiration hloov zuj zus tom qab ntawd kom siv cov pa oxygen.
Lub sijhawm ua pa ntawm tes tau hloov zuj zus lawm?
Lub hauv paus chiv keeb ntawm oxygenic photosynthesis nyob rau hauv Cyanobacteria coj mus rau qhov nce ntawm oxygen nyob rau hauv lub ntiaj teb ~ 2.3 billion xyoo dhau los, profoundly hloov txoj kev ntawm evolution los ntawm kev pab txhawb txoj kev loj hlob ntawm aerobic ua pa thiab complex multicellular life.
Ua pa hloov pauv li cas?
Ua pa, txheej txheem uas siv oxidant txhawm rau hloov lub zog ntawm cov metabolites mus rau lub pas dej phosphate, xav tias muaj ntau hom kev hloov pauv, los ntawm cov neeg siv cov oxidants uas tsis tshua muaj peev xwm, xws li sulfur., rau cov muaj zog ntau dua li TSIS MUAJ lossis nitric acid thiab cov pa oxygen.
Kev ua pa ntawm tes txhawb nqa kev hloov pauv li cas?
Kev ua pa ntawm tes yuav tau hloov zuj zus los ntawm kev hloov kho cov txheej txheem photosynthetic kom rho tawm lub zog los ntawm cov zaub movLwm cov prokaryotes muaj ntau haiv neeg hauv lawv cov metabolism; qee qhov xav tau oxygen, lwm tus tuaj yeem nyob tsis muaj nws. Cov kab mob uas tsis siv oxygen hauv lawv cov metabolism yog hu ua anaerobes.
Puas ua pa hloov pauv ua ntej photosynthesis?
Photosynthesis thiab ua pa, ob qho tib si siv electron ntws ua ke nrog phosphorylation, muaj ib qho hauv paus chiv keeb ('conversion hypothesis'), tab sis photosynthesis tuaj ua ntej Anaerobic (nitrate lossis sulphate) ua pa tsis tuaj yeem tau ua ntej photosynthesis li tsis muaj nitrate los yog sulfate muaj nyob rau hauv lub ntiaj teb thaum ntxov.
