respiration

• Reasons why Actual number of Net ATP synthesised is less than the theoretical number
• Reasons why Actual number of Net ATP synthesised is less than the theoretical number

  1. ATP/energy used to transport pyruvate/reduced NAD/products of glycolysis into (named part of) mitochondria

  2. Some protons leak from intermembrane space

  3. Some energy lost as heat

  4. Glucose may not be completely broken down / some intermediates are used in different metabolic processes

  5. Reduced NAD may be used for other (metabolic) reactions
• Oxidative phosphorylation
• Oxidative phosphorylation


  1. Reduced NAD/FAD releases hydrogen/hydrogen splits into proton and electron

  2. Electrons pass through electron transport chain/ETC

  3. Protons transferred through inner membrane / into intermembrane space

  4. Proton gradient established/high proton concentration in intermembrane space

  5. Protons diffuse through ATP synthase

  6. ATP produced from ADP and Pi

  7. Oxygen acts as final electron acceptor (to form water)/described
• Difference Between Anaerobic respiration in mammals and in yeasts
• Similarities between anaerobic respiration in mammals and yeasts


  • Occur in cytoplasm
  • Involve glycolysis
  • Make 2 (net)/small amount of ATP
  • Regenerate NAD (from NADH)
• Differences between anaerobic respiration in mammals and yeasts

  • Mammalian tissue: H acceptor/reduction of pyruvate/pyruvic acid to lactate lactic acid

  Yeast cells: H acceptor/reduction of pyruvate/pyruvic acid to ethanol

  Mammalian tissue: No CO2/decarboxylation

  Yeast cells: CO2

  Mammalian tissue: Enzyme is lactate dehydrogenase

  Yeast cells: Enzyme is ethanol dehydrogenase

  Mammalian tissue: One/1 step/stage

  Yeast cells: Two/2 steps/stages

  Mammalian tissue: Reversible process

  Yeast cells: Irreversible process
• How bio sensor works
• How bio sensor works

  1. Blood on pad/strip inserted into biosensor/glucometer

  2. Glucose oxidase

  3. Glucose -> gluconic acid and hydrogen peroxide

  4. Electric current / flow of electrons / voltage

  5. Current proportional to glucose, quantity / concentration

  6. Digital/numerical, reading (on screen)
• Reasons why ATP is the universal energy currency
• Reasons why ATP is the universal energy currency

  • Water soluble
  • Easily transported around the cell
  • ATP loses P1/phosphate group
  • Hydrolysed by ATPase/(ATP is) stable molecule
  • To release energy, immediately / in small packets
• Difference between chemiosmosis in mitochondria and in chloroplast
• Chemiosmosis in mitochondria


  • Oxidative phosphorylation
  • Inner mitochondrial membrane / crista(e)
  • Reduced NAD/reduced FAD, give e-/H+
  • Intermembrane space
  • Oxygen, final, e-/H+, acceptor
  • Makes water/H2O
• Chemiosmosis in chloroplasts


  • Photophosphorylation
  • Thylakoid membrane
  • Photolysis/water/PS1/chlorophyll, give e-/H+
  • Thylakoid, space / lumen
  • NADP final, e/H+, acceptor
  • Makes reduced NADP
• Roles of NAD and FAD
• Roles of NAD and FAD

  • Coenzymes
  • Help/for, dehydrogenases/dehydrogenation (reactions)
  • Carry/transfer/transport/bring, hydrogens/H
  • To, ETC/inner mitochondrial membrane/crista(e)
• Structure of mitochondria and its functions
• Structure of mitochondria


  • Double membrane / outer and inner membrane / envelope

  Inner membrane folded cristae, to increase / for large, surface area

  Has ATP synthase / stalked particles

  Has ETC/carrier (proteins) / cytochromes

  Impermeable to protons

  Intermembrane space has low pH/high concentration of protons

  Protons pumped into intermembrane space

  Proton gradient between intermembrane space and matrix

  Matrix contains (co)enzymes for link reaction / the Krebs cycle

  Outer membrane permeable to pyruvate / reduced NAD / oxygen
• Functions of mitochondria
• How glucose Is converted to acetyl CoA
• How glucose Is converted to acetyl CoA

  1. Glycolysis

  2. Glucose phosphorylated by ATP to fructose (1,6-)bisphosphate

  3. Lysis/splits, to form 2 x triose phosphate

  4. Triose phosphate has hydrogen removed/is dehydrogenated/ is oxidised

  5. Reduced NAD formed

  6. 4x ATP/net 2ATP, produced

  7. Substrate-linked phosphorylation

  8. Pyruvate produced enters mitochondrial matrix

  9. Link reaction

  10. Pyruvate decarboxylated/carbon dioxide removed

  11. Pyruvate has hydrogen removed/is dehydrogenated/is oxidised

  12. Combines with coenzyme A