Which pathway takes place during aerobic/anaerobic to produce ATP?

Answer 1

Aerobic Respiration

Aerobic respiration occurs in the presence of oxygen and is the most efficient way of producing ATP. It includes the following stages:

1) Glycolysis: This process takes place in the cytoplasm and begins with glucose, which is broken down into two molecules of pyruvate. Glycolysis produces a net gain of 2 ATP molecules and 2 NADH molecules.

2) Pyruvate Oxidation: In the presence of oxygen, pyruvate is transported into the mitochondria where it is converted into acetyl-CoA, producing NADH in the process.

3) Citric Acid Cycle (Krebs Cycle): Acetyl-CoA enters the citric acid cycle (occurs in the mitochondrial matrix), which generates ATP, NADH, and FADH2 through a series of enzyme-catalyzed reactions.

4) Oxidative Phosphorylation (Electron Transport Chain and Chemiosmosis): This final stage occurs in the inner mitochondrial membrane. The NADH and FADH2 produced in earlier stages donate electrons to the electron transport chain, which pumps protons across the membrane, creating a proton gradient. The flow of protons back through ATP synthase drives the synthesis of a significant amount of ATP (approximately 26 to 28 ATP molecules per glucose molecule).

Anaerobic Respiration

Anaerobic respiration occurs in the absence of oxygen and is less efficient than aerobic respiration. It includes:

1) Glycolysis: As in aerobic respiration, glycolysis is the first step and occurs in the cytoplasm, yielding 2 ATP molecules and 2 NADH molecules from glucose.

2) Fermentation: To regenerate NAD+ needed for glycolysis (as oxygen is not available to accept the electrons and regenerate NAD+), cells undergo fermentation. In muscle cells, this results in the conversion of pyruvate into lactate (lactic acid fermentation). In yeast and some bacteria, pyruvate is converted into ethanol and carbon dioxide (alcoholic fermentation). Fermentation does not produce additional ATP beyond what is generated in glycolysis.

Answer 2

Greetings!

Different pathways occur in the aerobic and the anaerobic pathways.

With the aerobic pathway (which utilizes oxygen), glucose will be utilized going through glycolysis -> krebs cycle -> electron transport chain which would produce significantly more ATP compared to the anaerobic cycle.

In the anaerobic cycle (that does not utilize oxygen), similar to the aerobic cycle, will utilize glucose in the glycolysis pathway, then will undergo fermentation (either alcohol fermentation or lactate fermentation). However, very few ATP is made per glucose molecule in the anaerobic pathway.

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