3.5.2: Respiration

• -> Label all the stages of glycolysis, from A-G

  • A -> phosphorylation (of glucose)
  • B -> oxidation (of triose phosphaate)
  • C -> phosphorylation (of glucose) to glucose phosphate
  • D -> phosphorylation (of glucose phosphate) to hexose bisphosphate
  • E -> oxidation of 2 x triose phosphate to 2 x pyruvate
  • F -> 4 x ATP synthesis from 4ADP + 4Pi
  • G -> 2 x reduction of NAD to NADH/reduced NAD

  
• In stage 1 of glycolysis, phosphorylation of glucose occurs.

  • Glucose phosphorylated to glucose phosphate via ATP hydrolysis
  • Glucose phosphate phosphorylated to hexose bisphosphate via ATP hydrolysis
  • Hexose bisphosphate splits into 2 x triose phosphate
• In stage 2 of glycolysis, oxidation occurs.

  • 2 x triose phosphate oxidised to 2 x pyruvate
  • Reduction of 2NAD -> 2NADH / 2 x reduced NAD
  • Synthesis of 4ATP from 4ADP + Pi
  • Net gain of 2ATP
• Krebs' Cycle Diagram -> label all the stages

  • A - NAD
  • B - NADH / reduced NAD
  • C - FAD
  • D - FADH2 / reduced FAD
  • E - CO2
  • F - ADP + Pi
  • G - ATP

  
• Link Reaction diagram -> label all stages

  • A - pyruvate
  • B - NAD
  • C - NADH / reduced NAD
  • D - CO2
  • E - acetate
  • F - Coenzyme A

  
• Oxidative phosphorylation diagram -> Explain

  • NADH & FADH2 release H atoms (oxidised) into mitochondrial matrix -> NAD / FAD reformed -> return to glycolysis (NAD) /link reaction (NAD) /Krebs Cycle (NAD & FAD)
  • H atoms lose electrons (oxidised) -> electrons enter electron transport chain
  • Electrons transferred from electron carrier protein to electron carrier protein through series of redox
  • Releases energy -> enables ACTIVE TRANSPORT of H+ from matrix to INTERMEMBRANAL SPACE of mitochondrion

  
• Oxidative phosphorylation diagram -> Explain (pt.2)

  • H+/proton gradient established -> higher H+ conc. in intermembranal space compared to matrix
  • H+ move from intermembranal space to matrix via embedded ATP SYNTHASE -> CHEMIOSMOSIS
  • … which drives the SYNTHESIS of ATP from ADP + Pi
  • O2 acts as the final electron acceptor of electron transport chain -> combines with (2) H+ to form H2O