Cellular respiration

• What is cellular respiration?

  -        Cellular respiration the process by which cells create usable energy in the form of ATP from a series of biochemical reactions, involving the breakdown of glucose.

   

  -        The process of converting chemical energy stored in nutrients (glucose) into a usable form of energy as ATP. Occurs in all living organisms. Is a catabolic reaction. Anaerobic or aerobic pathways.
• What is Aerobic cellular respiration:

  -        Requires oxygen and mitochondria.

  -        More efficient (producing 30 OR 32 ATP per glucose molecule)

  Occurs in three stages:

  -        Glycolysis (in the cytosol)

  -        Krebs cycle (in the matrix of the mitochondria)

  -        Electron transport chain (in the cristae of the mitochondria)
• What is Anaerobic cellular fermentation?

  -        Does not require oxygen or a mitochondrion.

  -        Less efficient (producing only 2 ATP per glucose molecule)

  
  

  Occurs in two stages (both in the cytosol):

  -        Glycolysis – breaks down glucose into pyruvate, producing 2 ATP.

  -        Fermentation – converts pyruvate (product depends on cell type).

  
  

  Animal cells:

  Glucose --> Lactic acid

  Yeast and plant cells:

  Glucose --> Ethanol + CO2
• Cellular respiration chemical equation:

  C6H12O6  +  6O2  --> 6CO2 + 6H2O
• Aerobic cellular respiration stages:

  1. Glycolysis (Cytosol):

  • Glucose
  • 2NAD+
  • 2 ADP, 2Pi

  2 Pyruvate, 2NADH

  2 ATP
• Aerobic cellular respiration stages:

  
• Anaerobic cellular fermentation: