Question

) the system's entropy D) the cell's energy equilibrium E) the heat content of a chemical system In the presence of oxygen, the three-carbon however, the pyruvate (1) loses a carbon, which is given off as a m compound called acetate, and (3) is bonded to coenzyme A. compound pyruvate can be catabolized in the citric acid cycle. First, olecule of CO2, (2) is oxidized to form a two-carbon 10) These three steps result in the formation of 10) A) acetyl CoA, O2, and ATP. B) acetyl CoA, FADH2, and CO2 C) acetyl CoA, FAD, H2, and CO2. D) acetyl CoA, NADH, H+, and CO2. E) acetyl CoA, NAD+, ATP, and CO2 11) The primary role of oxygen in cellular respiration is to A) combine with lactate, forming pyruvate. B) yield energy in the form of ATP as it is passed down the respiratory chain. C) act as an acceptor for electrons and hydrogen, forming water. D) catalyze the reactions of glycolysis. E) combine with carbon, forming CO2.

Answer 1

10.- The 3 steps given to you actually describe the whole process and the compunds produced, except one: NADH+H⁺. We can see that in the step 2, when is says "it is oxydized", to oxydize into acetate we need a NADH⁺ molecule. So the answer is option D) Acetyl CoA, NADH+H⁺ and CO₂

11.- The role of oxygen comes until the electron chain (after krebs cycle) as the final electron acceptor. So the answer is option C) Act as an acceptor for electrons and hydrogen, forming water