Pyruvate oxidation !

• What happens to the pyruvate

  -moves into the mitochondria for Kreb cycle

  -either cellular aerobic respiration (O2 present) or fermentation (no O2 present).
• How do the 2 pyruvate molecules produced during glycolysis enter the mitochondria

  they must pass through the outer membrane through large pores as it's less specific and through a pyruvate-specific membrane carrier in the inner membrane
• what does decarboxylation do to the pyruvate molecule
• How much energy from glucose does a molecule of pyruvate synthesised in glycolysis contain

  The two molecules of pyruvate that are synthesized by glycolysis still contain 75 % of the energy found in one molecule of glucose.
• how is carbon released in cellular respiration

  it's released in the form of waste CO2
• what is the condition for pyruvate to get transported inside the mitochondria

  there must be oxygen present
• what does the NADH do with the hydride ions electrons it carried from glycolysis

  it has to drop the hydrides onto the electron transport chain
• which enzyme takes cares of pyruvate when it enters the matrix

  Co enzyme A
• what does the pyruvate get converted to in the mitochondrial matrix

  it gets decarboxylated; the 3-carbon pyruvate gets converted to a 2-carbon acetyl CoA group as it loses a carboxyl (-COO-) group

  the lost Carbon is waste CO2
• what is the Coenzyme A

  a coenzyme that contains a sulfur atom on the end
• what happens to the acetyl CoA group after decarboxylation

  Decarboxylation is followed by oxidation of the remaining 2 carbon molecules, producing an acetyl group. Then a dehydrogenation reaction happens to NADH
• what happens in the dehydrogenation reaction of NADH


  2 electrons and a proton get transferred to NAD+, forming NADH and an H+ ion gets released into solution
• Steps of pyruvate oxidation

  1. pyruvate enters the matrix

  2. decarboxylation happens when it loses a carboxyl group and becomes 2 carbon molecule. this is catalysed by enzyme pyruvate dehydrogenase complex

  3. A. oxidation happens involving the loss of dihydrogen (dehydrogenation reaction) and this produces an acetyl group

  3. B. NAD+ gets reduced to NADH

  4. another enzyme attaches acetyl group to CoA generating acetyl CoA (fuel for krebs cycle). CoA carries the acetyl group to citric cycle
• what is the intermembrane space in the mitochondria

  it's a space fluid-filled between the two membranes
• what is the matrix of mitoc

  protein-rich fluid that fills the innermost space