Cellular respiration is the reason we as humans require oxyg

Cellular respiration is the reason we (as humans) require oxygen. Which stage(s) of respiration require(s) oxygen? (choose all that apply) Note: you must get this question entirely right for it to be counted correct.

Glycolysis

Pyruvate processing

Citric acid cycle

Electron transport & Oxidative phosphorylation

Solution

Glycolysis is the metabolic pathway in which the 6 – carbon glucose molecule is converted in to 2 molecules of 3 – carbon pyruvate molecule. The chemical energy in the form of ATP and reduced coenzymes like NADH are produced.

The pyruvate produced from glucose through glycolysis can be converted into acetyl CoA, lactate and ethanol. In humans under aerobic conditions pyruvate is converted to acetyl CoA by oxidation. The pyruvate formed in the cytosol during glycolysis is transported to mitochondrial matrix across 2 mitochondrial membranes. The oxidation of pyruvate to acetyl CoA takes place in the mitochondrial matrix.

Citric acid cycle involves a series of biochemical reactions that oxidize the acetyl part of acetyl CoA to the carbon dioxide. The formation of reduced coenzymes FADH₂ and NADH also take place during citric acid cycle.

Electron transport chain is series of biochemical reactions during which the electrons and hydrogen ions are passed from NADH and FADH₂ to intermediate carriers that react with molecular oxygen to form water. Therefore NADH and FADH₂ provide the electrons during electron transport chain.

The final electron acceptor in electron transport chain is molecular oxygen and results in the formation of water.

Therefore, oxygen is required in electron transport and oxidative phosphorylation process to act as final electron acceptor producing water.