Respiration

Cellular Respiration

• Cellular respiration is the process where cells break down glucose to release energy.
• It is a series of metabolic pathways that convert the energy in nutrients into ATP (adenosine triphosphate), the universal energy currency for cells.
• In eukaryotic cells, cellular respiration takes place in the mitochondria.

Stages of Respiration

• Glycolysis: This is the anaerobic phase of respiration, occurring in the cytoplasm, where glucose undergoes partial oxidation to form two molecules of pyruvate, releasing energy.
• Link Reaction and Krebs Cycle: These are aerobic stages taking place inside the mitochondria, where the pyruvate undergoes further oxidation to carbon dioxide, releasing more energy.
• Electron Transport Chain: Happens in the inner mitochondrial membrane, where the majority of ATP is generated. It is an aerobic process.

Aerobic vs Anaerobic Respiration

• Aerobic respiration requires oxygen to fully break down glucose and produces carbon dioxide and water as waste products. It generates a large amount of ATP.
• Anaerobic respiration does not require oxygen, and only partially breaks down glucose to produce lactic acid or ethanol and carbon dioxide, depending on the organism. It generates a lower amount of ATP compared to aerobic respiration.

Importance of Respiration

• Cellular respiration is crucial as it provides cells with the energy they need to function and carry out their specific roles.
• ATP produced in respiration powers all cellular processes including active transport, muscle contraction, nerve impulses, and synthesis of large molecules.
• Waste products of respiration, CO2 and H2O, are exhaled during breathing, helping maintain a balanced internal environment (homeostasis).