Chemiosmosis and electron transport chain

The final stage of energy transformation in cellular respiration includes:

  • the electron transport chain
  • oxidative phosphorylation of adenosine diphosphate (ADP) by chemiosmosis.

Citric acid cycle

The Krebs cycle (citric acid cycle) is a cyclical metabolic pathway that oxidizes acetyl-CoA to carbon dioxide and water, forming a molecule of adenosine triphosphate (ATP).


The transition reaction, which occurs in the matrix of the mitochondrion, is the first step in the process of aerobic cellular respiration.

Glycolysis steps

Glycolysis summary

Glycolysis (Embden–Meyerhof pathway) is the sequence of reactions converting glucose (or glycogen) to pyruvate or lactate, with the production of ATP.

The first stage of cellular respiration, glycolysis, takes place in the cytoplasm of the cell. It is an anaerobic process and does not require oxygen.

Cellular Respiration

Metabolic pathways that contribute to the production of ATP molecules in cells are collectively referred to as cellular respiration.