2.2 - cellular respiration

Cards (26)

  • define cellular respiration?
    a catabolic pathway which provides ATP for other anabolic reactions
  • cellular respiration is a series of enzyme controlled reaction
  • structure of adenosine triphosphate (ATP)?
    one adenosine molecule and three inorganic phosphate groups (Pi)
  • what are the three stages of cellular respiration?
    1. glycolysis
    2. citric acid cycle
    3. electron transport chain
  • glycolysis takes place in the cytoplasm
  • citric acid cycle takes place in the matrix of mitochondria
  • the electron transport chain takes place in the cristae of the mitochondria
  • define glycolysis?
    the breakdown of glucose to pyruvate in the cytoplasm
  • Pyruvate is converted to acetyl coenzyme A with the loss of carbon dioxide
  • the acetyl from acetyl CoA combines with oxaloacetate to form citrate
  • dehydrogenases remove hydrogen ions and electrons
  • NAD forms NADH
  • citrate is converted back into oxaloacetate, resulting in the generation of ATP and the release of carbon dioxide
  • the citric acid cycle can only occur in the presence of oxygen (aerobic conditions)
  • during glycolysis, there is a net gain of 2ATP
  • the energy investment stage is when glucose is converted into intermediates, requiring 2ATP
  • the energy pay off stage is where intermediates are converted into pyruvate, releasing 4ATP
  • NAD transports hydrogen ions and electrons to electron transport chain
  • What molecule produces ATP from ADP + Pi in the electron transport chain?
    ATP synthase
  • during the electron transport chain, hydrogen ions combine with electrons and oxygen to form water
  • describe the movement of ATP synthase in the electron transport chain?
    rotates
  • where does fermentation occur within the cell?
    cytoplasm
  • lactate can be converted back into pyruvate if oxygen becomes present
  • in animal cells during fermentation, pyruvate is converted to lactate in a reversible reaction
  • in plants and yeast during fermentation, pyruvate is converted to ethanol and carbon dioxide
  • less ATP are produced during fermentation than in aerobic respiration