1. Cell Respiration
Department of Biology, WCU

2. Metabolism Biochemical reactions Types
Anabolism (small to large, e.g. amino acids into proteins)
Catabolism (large to small, e.g. digestion, cell respiration)

3. Cell respiration Energy - ATP (movement, respiration)
Adenosine triphosphate (ATP)
glucose + O CO2 + H2O + ATP
Reactions
Glycolysis
Acetyl CoA
Krebs cycle
Electron transport chain

4. Chemical reactions Redox Oxidation (O2 gained or H+ lost)
oxidation, reduction
Oxidation (O2 gained or H+ lost)
C6H12O6 + 6O CO2 + 6H2O + ATP
glucose is oxidized to CO2
decrease in energy

5. Chemical reactions
Oxidation reactions

6. Chemical reactions Reduction reactions O2 lose or H+ gain
C6H12O6 + 6O2 6CO2 + 6H2O + ATP
glucose is reduced to H2O
increase in energy

7. Chemical reactions
Reduction reactions

8. ATP synthesis Reactions require energy Phosphorylation - energy
(protein synthesis, vesicles in Golgi, active transport)
Phosphorylation - energy
Dephosphorylation

9. Overview

10. Overview

11. Glycolysis Coenzymes NAD - nicatinamide adenine dinucleotide
glucose pyruvic acid + 2NADH + 2H+
Coenzymes
NAD - nicatinamide adenine dinucleotide
FAD - flavin adenine dinucleotide
NAD+ - oxidized
NADH - reduced

12. Glycolysis Summary Generated 2 ATP Used glucose, 2NAD+
Produced 2 pyruvic acid
Occurs in cytoplasm

13. Fate of pyruvic acid 1. Anaerobic metabolism
Conversion to lactic acid (strenuous exercise)
No further ATP produced

14. Fate of pyruvic acid 2. Aerobic metabolism
Conversion to Acetyl CoA (light exercise)
Additional ATP produced

15. Formation of acetyl CoA
Summary
1. Decarboxylation
carbon removal combines with O2
2. Oxidation
removal of H+ combines with NAD+
3. CoA
acetyl group + CoA acetyl CoA

16. Krebs cycle Summary Use 3 NAD+ Use 1 FAD Produce 2 CO2
Produce 1 ATP per Acetyl CoA

17. Electron transport chain
Summary
Series of redox reactions
NADH + H+ oxidized to NAD+
One H+ to cristae, one H+ to next carrier protein (reduction)
2 H + + 1/2 O2 = H2O, releases ATP
Process is slow

18. Electron transport chain

19. ATP Synthesis

20. Mechanisms of ATP synthesis
1. Substrate level phosphorylation
Use of an enzyme

21. Mechanisms of ATP synthesis
2. Oxidative phosphorylation
Energy used to pump H+, energy derived from diffusion gradient