Cellular Respiration

• What is glycolysis?


  The breakdown of glucose to pyruvate. This process occurs in the cytoplasm
• Describe the 'investment' stage of glycolysis:

  ATP (energy) is required for the phosphorylation of glucose and intermediate compounds. 2 ATP are required. ATP is broken down into ADP + Pi and it's the Pi (phosphate) which phosphorylases the glucose
• Describe the 'pay-off' stage of glycolysis:

  Dehydrogenase passes hydrogen ions to NAD forming NADH, and this yields 4 ATP, resulting in a net gain of 2 ATP
• What happens to the acetyl group from acetyl coenzyme A in the citric acid cycle?

  Combines with oxaloacetate to form citrate
• What is pyruvate converted into? (Aerobic conditions)

  Broken down into an acetyl group that combines with coenzyme A, forming acetyl coenzyme A
• Where does the citric acid cycle occur?

  Matrix of the mitochondria
• Where does the electron transport chain occur?

  Inner mitochondrial membrane
• What is the role of dehydrogenase enzymes?


  Remove hydrogen ions and electrons and pass them to coenzyme NAD, forming NADH.
• Where are the hydrogen ions and electrons from NADH passed?

  The electron transport chain on the inner mitochondrial membrane
• What is the electron transport chain?

  A series of carrier proteins attached to the inner mitochondrial membrane
• How is hydrogen able to be pumped across the inner mitochondrial membrane?

  Because of the energy released when electrons are passed from NADH along the electron transport chain
• How is ATP produced?


  Because of the flow of these ions back through the the membrane protein ATP synthase
• What product is formed at the end and how?

  Water; hydrogen ions and electrons combine with oxygen
• What is citrate converted back into and how?

  Oxaloacetate, by a series of enzyme controlled reactions