EVERYDAY SCIENCE

Detailed explanation-1: -In cellular respiration, glucose and oxygen react to form ATP. Water and carbon dioxide are released as byproducts. The three stages of aerobic cellular respiration are glycolysis (an anaerobic process), the Krebs cycle, and oxidative phosphorylation.

Detailed explanation-2: -Thus, if oxygen is not present, the respiratory cycle cannot function, which shuts down the Krebs cycle. For this reason, the Krebs cycle is considered an aerobic pathway for energy production.

Detailed explanation-3: -Under anaerobic conditions, especially during fermentative growth, during which NADH cannot be reoxidized by the respiratory chain, Krebs cycle activity is reduced to the minimum level needed to supply biosynthetic pathways and is transformed from a cyclic pathway to two oppositely oriented half-cycles.

Detailed explanation-4: -The stages of cellular respiration include glycolysis, pyruvate oxidation, the citric acid or Krebs cycle, and oxidative phosphorylation.

Detailed explanation-5: -Thus the correct order of the stages in cellular respiration is: Glycolysis-Oxidative decarboxylation-Krebs cycle-Electron transport chain-Oxidative phosphorylation.