Mehlala ea Lipotso tsa Puisano tsa Metabolism
Metabolism ke letoto la diketso tsa dikhemikhale tse etsahalang ka hara disele tsa dintho tse phelang ho boloka bophelo. Tshebetso ena e kenyeletsa mekhahlelo e mmedi e meholo: anabolism le catabolism. Anabolism ke ts'ebetso ya ho haha dimolekhule tse rarahaneng ho tloha ho tse bonolo, tseo hangata di hlokang matla. Catabolism ke ts'ebetso ya ho qhaqha dimolekhule tse rarahaneng ho ba tse bonolo, ka hona ho lokolla matla.
Thutong ea baeloji, metabolism ke sehlooho sa bohlokoa le se atisang ho ba phephetso bakeng sa baithuti. Ho u thusa ho utloisisa sehlooho sena hamolemo, re tla fana ka mehlala e 'maloa ea mathata le litlhaloso tsa ona.
Mohlala oa Potso ea 1: Tsela ea Glycolysis
Potso: Hlalosa mokhoa oa glycolysis 'me u ngole lihlahisoa tsa ho qetela tsa tsela ena.
Puisano:
Glycolysis ke tsela ea metabolism e hlahang ka har'a cytoplasm ea sele, moo molek'hule e le 'ngoe ea glucose (C6H12O6) e aroloang ho ba limolek'hule tse peli tsa pyruvic acid (C3H4O3). Ts'ebetso ena ha e hloke oksijene (anaerobic) 'me e etsahala ka mehato e leshome e susumetsoang ke lienzyme tse itseng.
1. Mehato ea ho Lokisetsa:
– Glucose e fetoloa Glucose-6-phosphate ke enzyme hexokinase.
– Glucose-6-phosphate ebe e fetoloa fructose-6-phosphate ke enzyme phosphoglucose isomerase.
– Fructose-6-phosphate e phosphorylated ho ba fructose-1,6-bisphosphate ke phosphofructokinase.
2. Mehato ea Karohano:
– Fructose-1,6-bisphosphate e arotsoe ka limolek'hule tse peli tsa khabone tse tharo: dihydroxyacetone phosphate le glyceraldehyde-3-phosphate.
3. Mehato ea ho Hlohlelletsa le Sebopeho sa ATP:
– Glyceraldehyde-3-phosphate e fetoloa ho ba 1,3-bisphosphoglycerate ke dehydrogenase.
– Phosphate e fetisetsoa ho tloha ho 1,3-bisphosphoglycerate ho ea ho ADP ho etsa ATP le 3-phosphoglycerate.
– 3-phosphoglycerate ebe e fetoloa phosphoenolpyruvate.
– Qetellong, phosphate e tswang ho phosphoenolpyruvate e fetisetswa ho ADP ho etsa ATP le pyruvate.
Lihlahisoa tsa ho qetela tsa glycolysis ke limolek'hule tse peli tsa pyruvic acid, limolek'hule tse peli tsa ATP tse hloekileng (ho hlahisoa ATP tse 'ne empa tse peli li sebelisoa hape), le NADH tse peli.
Mohlala oa Potso ea 2: Sekepe sa Krebs
Potso: Hlalosa karolo ea potoloho ea Krebs metabolism ea matla a sele 'me u thathamise lihlahisoa tse kholo tsa potoloho e le' ngoe.
Puisano:
Potoloho ea Krebs, e tsejoang hape e le potoloho ea citric acid kapa potoloho ea TCA, ke tsela ea metabolism e etsahalang mitochondria. Ts'ebetso ena e hloka oksijene (aerobic) 'me e bapala karolo ea ho hlahisa limolek'hule tse nang le matla a mangata tse kang NADH le FADH2, tse sebelisoang ketane ea lipalangoang tsa lielektrone ho hlahisa ATP.
Qalong ea potoloho ea Krebs, molek'hule ea acetyl-CoA e kopana le oxaloacetic acid (4C) ho theha citric acid (6C). Asiti ea citric ebe e feta letotong la liketso tse nchafatsang oxaloacetic acid, ha ka nako e ts'oanang e lokolla limolek'hule tse peli tsa CO2, 'me e hlahisa NADH, FADH2, le ATP (kapa GTP).
Liphetho tse ka sehloohong tsa phetoho e le 'ngoe ea potoloho ea Krebs (ho qala ka acetyl-CoA e le 'ngoe) ke:
– Limolek'hule tse 3 tsa NADH
– molek'hule e le 'ngoe ea FADH2
– molek'hule e le 'ngoe ea ATP (kapa GTP)
– limolek'hule tse 2 tsa CO2
NADH le FADH2 di tla fetolelwa ho ATP ka ketane ya dipalangwang tsa dielektrone.
Mohlala oa Potso ea 3: Ketane ea Lipalangoang tsa Elektrone
Potso: Hlalosa kamoo ketane ea lipalangoang tsa lielektrone e bapalang karolo tlhahisong ea ATP 'me u bolele sebaka sa ts'ebetso ena ka seleng.
Puisano:
Ketane ea ho tsamaisa lielektrone (ETC) ke karolo ea ho qetela ea ho hema ha sele 'me e hlaha ka har'a lera le ka hare la mitochondria. Karolo ea eona ea mantlha ke ho hlahisa ATP ka phosphorylation ea oxidative.
NADH le FADH2, tse hlahisoang ke glycolysis le potoloho ea Krebs, li kenya letsoho lielektrone ho ketane ena. Lielektrone li phalla ka har'a letoto la likarolo tse rarahaneng tsa protheine tse kenelletsoeng ka har'a lera la mitochondrial. Matla a lokolloang ha lielektrone li phalla a sebelisoa ho pompa liprothone (H+) ho tloha matrix ea mitochondrial ho ea sebakeng sa intermembrane, e leng se etsang hore proton e be gradient.
Gradient ena ea proton e hlahisa matla a ka bang teng a tsejoang e le matla a proton-motive. Liproton li khutlela matrix ka ATP synthase, e leng enzyme e sebelisang phallo ena ea proton ho hlahisa ATP ho tsoa ho ADP le phosphate e sa tloaelehang.
Ka kakaretso, ts'ebetso ea ETC e ka hlahisa hoo e ka bang 34 ATP ka molek'hule ea tsoekere e kopantsoeng.
Lipotso le Lipuisano tse Eketsehileng
Hape ho bohlokoa ho leka lipotso tse ling tse lekang kutloisiso ea hau ea li-enzyme tse amehang, liphapang lipakeng tsa ho hema le ho bela ha sele, le litlamorao tsa maemo a tikoloho (joalo ka ho fumaneha ha oksijene) ho metabolism.
Lipotso tse ling:
1. Ke hobane'ng ha NAD+ e le ea bohlokoa ho glycolysis?
2. Bapisa ho hema ka aerobic le ho belisoa ha metsoako mabapi le katleho ea tlhahiso ea ATP.
3. Hlalosa kamoo metabolism ea mafura a mafura e amanang le potoloho ea Krebs.
Ho ithuta metabolism ho hloka kutloisiso e tebileng ea biochemistry le fisioloji ea lisele. Keletso e molemohali ke ho tsoela pele ho ikoetlisa ka mathata, lipuisano tsa lihlopha tsa thuto, le liteko tsa laboratori ho matlafatsa likhopolo tsena. Re tšepa hore sengoloa sena se tla u thusa ho tebisa kutloisiso ea hau ea metabolism le ho itokisetsa lipotso tse amanang le eona tlhahlobong ea hau.
