Question

Choose the correct answers from the alternatives given :
Which of the following is a true distinction between fermentation and cellular respiration?

• A. NAD functions as an oxidising agent only in respiration
• B. Substrate-level phosphorylation is unique to fermentation
• C. Fermentation, but not respiration, is an example of a catabolic pathway
• D. $NA{D}^{+}$ is reduced by the electron transport chain only in respiration

Answer 1

The correct option is D $NA{D}^{+}$ is reduced by the electron transport chain only in respiration

• Fermentation is the process that takes place in the cells which perform anaerobic respiration.
• Where as cellular respiration is a form of aerobic respiration.
• In aerobic respiration, kerb cycle takes place in the mitochondria where with the transport of H ions and electrons formation of ATP takes place.
• For this transport of electron and H ions electron transport chain is required which is present in mitochondria and mitochondria is used only during aerobic respiration and not in anaerobic respiration.
• There NAD will not be reduced by the electron transport system in Fermentation (anaerobic respiration). Only the formation of lactic acid and one molecule of NADH takes place at the end of fermentation.
• Therefore the answer option 'NAD+ is reduced by the electron transport chain only in respiration' is correct.