Name: cellular respiration: atp production pathways
Uploaded: 2025-06-12T09:34:08.000Z
Duration: 1 min 18 s
Channel: JoVE

Cellular respiration is a biochemical process that generates ATP through the oxidation of molecules, using an external electron acceptor.It begins with glycolysis, converting glucose into pyruvate while producing ATP and NADH.Pyruvate enters the Krebs cycle, occurring in the cytoplasm of prokaryotes or the mitochondrial matrix of eukaryotes, generating NADH and FADH2.Electrons from these carriers pass through the electron transport chain, located in the plasma membrane of prokaryotes and the inner mitochondrial membrane of eukaryotes, producing ATP via oxidative phosphorylation.Aerobic respiration uses oxygen as the electron acceptor and can produce up to 38 ATP per glucose molecule in prokaryotes.In eukaryotes, the net yield is about 30 to 32 ATP, as some energy is consumed during NADH shuttling.Some prokaryotes and eukaryotes undergo anaerobic respiration that utilizes alternate electron acceptors such as nitrate or sulfate as the electron acceptor with less ATP yields.

ademhaling

Cellular Respiration

Cellulaire respiratie is een cruciaal metabolisch proces waarbij cellen energie verkrijgen uit organische stoffen, voornamelijk glucose, om adenosinetrifosfaat (ATP) te produceren. Dit proces omvat de oxidatie van substraten en de overdracht van elektronen naar een afzonderlijke elektronacceptor, waarmee ATP-synthese mogelijk wordt gemaakt via een reeks biochemische reacties.
Glycolyse: De initi&#235;le stap
Glycolyse is de eerste fase van cellulaire respiratie en vindt plaats in het cytoplasma van zowel prokaryote als eukaryote cellen. Het omvat de afbraak van &#233;&#233;n glucosemolecuul (C_6 H_12 O_6) tot twee moleculen pyruvaat (C_3 H_4 O_3), met een netto-opbrengst van 2 ATP en 2 NADH. Dit proces vereist geen zuurstof en fungeert als voorbereidende stap voor zowel aerobe als anaerobe respiratie.
De citroenzuurcyclus: Generatie van elektronenoverdrachtsmoleculen
Pyruvaat ondergaat een cruciaal proces, decarboxylering genaamd, waarbij het wordt omgezet in acetyl-CoA. Dit nieuwgevormde acetyl-CoA treedt vervolgens de citroenzuurcyclus binnen, ook bekend als de Krebs-cyclus of tricarbonzuurcyclus. Deze complexe reeks biochemische reacties vindt plaats in het cytoplasma van prokaryoten en in de matrix van mitochondri&#235;n bij eukaryoten.
Wanneer acetyl-CoA door de citroenzuuryclus beweegt, speelt het een essenti&#235;le rol in de energieproductie. Voor elk verwerkt molecuul acetyl-CoA produceert de cyclus drie moleculen NADH, &#233;&#233;n molecuul FADH_2 en &#233;&#233;n GTP. Deze elektronenoverdrachtsmoleculen, NADH en FADH_2, zijn essentieel voor het aandrijven van ATP-synthese in daaropvolgende reacties. Bovendien wordt koolstofdioxide (CO_2) als bijproduct vrijgegeven tijdens dit proces, hetgeen bijdraagt aan de algemene metabolische activiteiten van de cel.
Elektronentransportketen en oxidatieve fosforylering
De elektronentransportketen (ETC) bevindt zich in het plasmamembraan van prokaryoten, terwijl deze bij eukaryoten is gelokaliseerd in het binnenste mitochondriale membraan. Elektronen afkomstig van NADH en FADH_2 worden doorgegeven via een reeks eiwitcomplexen, waarbij een protonengradi&#235;nt over het membraan wordt gecre&#235;erd. De terugstroom van protonen via ATP-synthase drijft de fosforylering van ADP tot ATP aan. In aerobe respiratie fungeert zuurstof als de uiteindelijke elektronacceptor, waarbij water (H_2O) wordt gevormd.
ATP-opbrengst en alternatieve elektronacceptoren
Aerobe respiratie kan tot 38 ATP-moleculen per glucose opleveren bij prokaryoten, terwijl de netto ATP-productie bij eukaryoten ongeveer 30&#8211;32 bedraagt vanwege het energieverlies bij het transport van NADH naar de mitochondri&#235;n. Bij anaerobe respiratie gebruiken prokaryoten en sommige eukaryoten alternatieve elektronacceptoren zoals nitraat (NO_3^-), sulfaat (SO_4^2-) of koolstofdioxide (CO_2), wat leidt tot een aanzienlijk lagere ATP-opbrengst&#8212;typisch rond de 2 ATP per glucose&#8212;vanwege de lagere effici&#235;ntie van deze acceptoren in het genereren van een protonengradi&#235;nt.
Cellulaire respiratie is essentieel voor het energiemetabolisme, doordat organismen daarmee hun cellulaire functies kunnen behouden. De effici&#235;ntie en keuze van de elektronacceptor bepalen de energieopbrengst en de metabole aanpassingen van verschillende organismen in uiteenlopende omgevingen.

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Cellulaire respiratie is een cruciaal metabolisch proces waarbij cellen energie verkrijgen uit organische stoffen, voornamelijk glucose, om ...

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cellular respiration: atp production pathways

Cellular respiration is the process cells use to turn glucose into ATP, the main energy molecule in the cell. It depends on oxidation and the transfer of electrons to a separate electron acceptor. This sequence of reactions supports energy production in both aerobic and anaerobic settings.

Glycolysis is the first step. It takes place in the cytoplasm of both prokaryotic and eukaryotic cells. One glucose molecule is broken into two pyruvate molecules, and the cell gains a net 2 ATP and 2 NADH. Glycolysis does not require oxygen, so it can support both aerobic and anaerobic respiration.

Pyruvate then undergoes decarboxylation and becomes acetyl-CoA. Acetyl-CoA enters the Krebs cycle, also called the citric acid cycle or tricarboxylic acid cycle. In prokaryotes, this cycle occurs in the cytoplasm. In eukaryotes, it occurs in the mitochondrial matrix. Each acetyl-CoA produces 3 NADH, 1 FADH2, and 1 GTP. The cycle also releases carbon dioxide as a byproduct.

The electron transport chain, or ETC, uses the NADH and FADH2 made earlier. In prokaryotes, the ETC is in the plasma membrane. In eukaryotes, it is in the inner mitochondrial membrane. Electrons move through protein complexes and create a proton gradient across the membrane. ATP synthase uses the return flow of protons to convert ADP into ATP. In aerobic respiration, oxygen is the final electron acceptor, and water forms.

Aerobic respiration can yield up to 38 ATP per glucose in prokaryotes. In eukaryotes, the net yield is about 30 to 32 ATP because energy is used to move NADH into mitochondria. Some organisms also use anaerobic respiration. In that pathway, alternative electron acceptors such as nitrate, sulfate, or carbon dioxide are used. This form makes much less ATP, usually around 2 ATP per glucose, because these acceptors build a weaker proton gradient. Cellular respiration is therefore essential for ATP production and for the energy metabolism that keeps cells functioning.

Cellular Respiration: ATP Production Pathways

cellular-respiration-atp-production-pathways

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cellular respiration

Cellular respiration is the process cells use to turn glucose into ATP, the main energy molecule in the cell. It depends on oxidation and the transfer of electrons to a separate electron acceptor. This sequence of reactions supports energy production in both aerobic and anaerobic settings. Glycolysis is the first step. It takes place in the cytoplasm of both prokaryotic and eukaryotic cells. One glucose molecule is broken into two pyruvate molecules, and the cell gains a net 2 ATP and 2 NADH.

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key terms and concepts

Learn how cells make ATP through glycolysis, the Krebs cycle, and the electron transport chain, plus how aerobic and anaerobic respiration differ.

Cellular Respiration: ATP Production Pathways | JoVE K12

JoVE Core Microbiology provides an engaging introduction to the microbial world and its influence on health, industry, and the environment. This comprehensive collection covers key concepts such as microbial structure, metabolism, genetics, and ecology. It introduces essential laboratory techniques and microscopy methods through visually engaging animations. Corresponding scientist-in-action videos bridge classroom concepts with real-world research and applications.

microbiology

Cellular Respiration: ATP Production Pathways

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