21. What is the best explanation of ATP utilization and production? A. ATP is being recycled from the process glycolysis, undergo oxidation process and later it is being remade during

Krebs cycle

B. ATP is used to reduced carbon molecule to produce oxaloacetate and used for the bulk reproduction of ATP

during electron transport chain

C. ATP is used during energy investment phase to harvest the energy stored in the molecule 2,3 – carbon molecule

during the energy harvesting phase

D. ATP is adenosine triphosphate that has 3 phosphate groups attached and it is being reduced into Adenosine

diphosphate after losing one phosphate group in its molecule

22. The best description on the role of oxygen during respiration is .

A. Oxygen is used to phosphorylate ADP to ATP

B. Oxygen is used to oxidize carbon dioxide to form glucose

C. Oxygen is utilized to add carbon in carbon dioxide as a by-product of cellular respiration

D. Oxygen is used to oxidize glucose molecule to form ATP—the energy needed by the body

23. Where are the 36 ATP come from during cellular respiration?

A. 2 from glycolysis, 2 from oxidation of pyruvate and 32 from Krebs cycle

B. 2 from glycolysis, 2 from Krebs cycle and 32 from electron transport chain

C. 2 from glycolysis, 2 from oxidation of pyruvate and 32 from electron transport chain

D. 2 from oxidation of pyruvate, 2 from Krebs cycle and 32 from electron transport chain​