aerobic respiration

• what are the stages of aerobic respiration?

  1. glycolysis

  2. link reaction

  3. krebs cycle

  4. oxidative phosphorylation
• whats the gross production of glycolysis? and whats the net yeild of atp?

  4 ATP, 2 pyruvates , 2 NADH the net production of ATP is 2
• describe/draw out the steps of glycolysis?

  1. glucose enters the cytoplasm via facilitated diffusion
  2. upon entrance, phosphorylation occurs as an enzyme adds 2 phosphates from the hydrolysis of 2 ATP molecules producing glucose phosphate
  3. the glucose phosphate splits into two molecules of triose phosphate
  4. the triose phosphates then get oxidised to pyruvate and lose H+ to NAD becoming oxidised to NADH
  5. 2 ATPs are produced from this redox reaction
• why are phosphates added to glucose?


  to prevent it leaving the cell and to make it more reactive
• where does glycolysis take place?


  cytoplasm
• where does the link reaction take place?

  mitochondrial matrix
• describe the process of the link reaction?

  1.pyruvate moves into the mitochondrial matrix via cotransport facilitated by active transport

  2. one carbon is removed from pyruvate as carbondioxide producing acetate, pyruvate is also oxidised losing a H+ to NAD which gets reduced to NADH

  3. coenzyme A joins acetate to produce acetylcoenzymeA
• where does the krebs cycle take place?

  mitochondrial matrix
• describe the krebs cycle?

  1. acetylecoA reacts with a molecule containing 4 carbons to produce a 6 carbon molecule
  2. the 6 carbon molecule then loses 2 carbons as carbondioxide
  3. it also oxidised and loses H+ ions
  4. 2ATP molecules are produces
  5. 3NaADHs produced
  6. FADH2 is produces
  7. the 6 carbon molecule converts back to the 4 carbon molecule
• why was coenzyme a added to acetate just to be removed?

  becuase an enzyme is required to catalyse the reaction between acetylcoenzyme a and the 4 carbon compound and for that enzyme to function, a coenzyme is required
• what is substrate level phosphorylation?

  when a molecule donates a phosphate uses an enzyme
• how are tryglycerides used in respiration?

  glycerol can be converted to triose phosphate so it can be used in glycolysis

  1 fatty acid can be converted to acetylcoenzymeA used in the krebs cycle
• how are amino acids used in respiration?

  1. first remove the amine group

  amino acids with three carbons can be converted to pyruvate which can then be used in the link reaction

  amino acids with 4 or 5 carbons can be converted to intermediates which can be used in the krebs cycle
• where does oxidative phosphorylation take place?

  inner mitochondrial membrane
• describe the process of oxidative phosphorylation ?

  1. H+ ions move through ATP synthase via chemiosmosis for the phosphorylation of ATP
  2. to maintain the proton gradient NADH and FADH2 donate electrons to protein in the electron transfer chain so become oxidised NADH and FADH2 also release protons
  3. the electrons travel through the electron transfer chain via redox reactions releasing energy for the active transport for H+ ions from the matrix to the intermembrane space
  4. at the end of the electron transfer chain, oxygen reacts with electron and protons in the matrix to produce water
• what is oxygen known as?

  the final electron acceptor
• why do H+ move through ATP synthase?

  to change the shape of the enzyme to allow for phosphorylation
• describe the adaptations of mitochondria?

  1. the inner membrane of the mitochondria folds to form cristae to provide a large surface area for oxidative phosphorylation so alot of ATP can be produced
  2. the number of cristae depends on the amount of ATP required for the cell