Question

What happens to glycolysis if the oxygen is present

Answer 1

Glycolysis proceeds to the aerobic respiration pathways when oxygen is present, leading to a higher ATP yield and complete oxidation of pyruvate in the mitochondria.

Step-by-step explanation:

When oxygen is present in the cell, glycolysis is followed by the aerobic respiration pathways namely the Krebs cycle and the electron transport chain. This total process generates a higher yield of ATP compared to glycolysis alone. The presence of oxygen ensures that the NADH produced during glycolysis can be oxidized back into NAD+, which is crucial for the continuation of the glycolysis process. In aerobic conditions, pyruvate produced at the end of glycolysis is sent to the mitochondria for complete oxidation, ultimately producing CO2, H2O, and a significant amount of ATP.

Glycolysis is the first step in cellular respiration and occurs in the cytoplasm of cells. Normally, glycolysis can proceed either aerobically or anaerobically. If oxygen is present, glycolysis is followed by the Krebs cycle and electron transport, which produce a much larger amount of ATP compared to glycolysis alone. On the other hand, in the absence of oxygen, an alternate pathway called fermentation occurs to keep glycolysis going and to regenerate the necessary NAD+ for glycolysis.

Answer 2

when no oxygen is present, there is no electron acceptor, thus pyruvate goes through a process known as fermentation which usually forms lactic acid or ethanol as a by-product. During lactic acid fermentation, pyruvate is reduced directly by NADH to form lactate as a waste product, with no release of CO2.