Which of the following steps does not take place during cellular respiration? a: glucose is broken down. b: energy is transferred to cells. c: oxygen combines with carbon dioxide. d: energy and other products are released.

C: Oxygen combines with carbon dioxide.

Explanation:

Cellular respiration is a biological process, by which complex molecules, such as glucose is breakdown to produce energy in the form of ATP molecules.

During cellular respiration, glucose molecules are completely oxidized in the presence of oxygen to form ATP molecules, while water and carbon dioxide are formed as byproduct of the reaction.

Hence, oxygen is a reactant and carbon dioxide is a product of cellular respiration that do not combine during this process.

Thus, the correct answer is option (C).

cell regulation is conducted by special proteins.