Question

All of the following proceses involves the breakdown of carbon compounds, except

• A. Glycolysis.
• B. Calvin cycle.
• C. Respiration.
• D. Krebs cycle.
• E. Fermentation.

Answer 1

The correct option is B Calvin cycle.

Aerobic respiration is breakdown of sugar/other food substances in presence of oxygen to released energy. It includes glycolysis, Kreb cycle and electron transport chain. Glycolysis and Kreb cycle produce reducing compounds NADH, FADH2 which are then oxidized in presence of oxygen by the process of chemiosmosis and reduce oxygen to water. Fermentation is incomplete oxidation of food substances into alcohol and lactic acid with small amount of energy being released. Both lactic acid and ethanol fermentation do not produce oxygen. Calvin cycle is fixation of atmospheric carbon dioxide into organic compounds using the energy produced in light reactions of photosynthesis. This makes option B correct.