2.2 Cellular Respiration

• Describe the term 'phosphorylation'

  Phosphorylation is an enzyme controlled reaction which describes the addition of an inorganic phosphate (Pi) to another molecule. The molecule is then said to be phosphorylated.
• State the 3 stages of cellular respiration and the locations where they occur.
• State the 3 stages of cellular respiration and the locations where they occur.

  1. Glycolysis- Cytoplasm.
  2. Citric acid cycle- Matrix of Mitochondria.
  3. Electron transport chain- Inner mitochondrial membrane.
• State what substance is formed when Acetyl Co A and oxaloacetate combine.

  Citrate.
• Fill in the blanks.

  During a series of enzyme controlled steps, citrate is gradually converted back to oxaloacetate which results in the generation of ATP and the release of Carbon dioxide.
• Explain why less energy is produced during fermentation than Aerobic respiration in animal cells.

  The electron transport chain does not operate and this major source of ATP is unavailable to the cell.
• Explain the purpose of the co-enzyme NAD with cellular respiration.

  Picks up hydrogen ions and electrons during the pay off phase and citric acid cycle then delivers them to the electron transport chain.
• State the purpose of Dehydrogenase enzymes during the stages of glycolysis and the citric acid cycle.

  Release hydrogen ions and electrons during the pay off phase of glycolysis and during the citric acid cycle.
• State the difference between the process of fermentation in yeast cells and in muscle cells.

  -In animal cells, pyruvate is converted to lactate in a reversible reaction.

  -In plants and yeast cells, ethanol and CO2 are produced in an irreversible reaction.
• State the final hydrogen acceptor in the electron transport chain.

  Oxygen.
• What is the membrane protein responsible for synthesis of ATP in the electron transport chain?

  ATP synthase.
• where does fermentation take place in both animals and plants?

  Cytoplasm.