1. Metabolism Catabolism-Glycolysis (Kreb Cycle) Anabolism-Photosynthesis

2. Metabolism Sum of all chemical reactions Catabolism –Exergonic reaction –Most of energy in ATP –last phosphate bond

3. Metabolism Anabolism –Consume more energy than produce –Use ATP for energy

4. Enzymes Biological catalysts Energy of activation Specificity Primary structure Secondary structure Tertiary structure Quaternary structure

5. Components of Enzymes Apoenzyme-protein only Cofactor-nonprotein –Trace elements Coenzyme-organic cofactor –Carriers of electrons etc –NAD+

6. Enzyme-substrate Complex Active site on enzyme Transformation in substrate Products released Enzyme orients substrate Lowers energy of activation

7. Denaturation Structure of enzyme is disrupted No longer active Temperature pH Substrate concentration –Enzyme becomes saturated

8. Inhibitors Competitive inhibitors Noncompetitive inhibitors –Allosteric site

9. Feedback Inhibition End product inhibition Series of enzymes –end product

10. Energy Production Oxidation-reduction reactions Generation of ATP –Phosphorylation –Used for metabolism, binary fission, endospore formation movement

11. Types of Phosphorylation Substrate level Oxidative phosphorylation Photophosphorylation

12. Carbohydrate Metabolism Glucose as an example Two energy processes –Cellular respiration –Fermentation –Glycolysis Respiration-Krebs cycle & electron transport chain

13. Glucose Metabolism C 6 H 12 O 6 + 6O 2 + 38 ADP +38 P 6CO 2 + 6H 2 O + 38 ATP

14. Glycolysis Summary of glycolysis 2 molecules of pyruvate (3 C) Production of 2 NADH & 2H+ Net of 2 ATP Substrate phosphorylation Takes place in cytosol of bacteria & eukaryotes No oxygen is required Alternate pathways

15. Cellular Respiration Cellular respiration –Final electron acceptor is inorganic molecule Two types based on final electron acceptor

16. Aerobic Respiration Krebs cycle Mitochondria of eukaryotes-matrix Cytosol in prokaryotes Intermediary step- production of acetyl CoA –2 CO 2 & 2 NADH

17. Aerobic Respiration Acetyl Co enters Krebs cycle 4 carbons of glucose released as CO 2 6 NADH & 2 FADH2 produced 2 ATP by substrate phosphorylation

18. Electron Transport Chain Series of redox reactions Stepwise release of energy Oxygen final acceptor of electrons Inner membrane of mitochondria in eukaryotes Foldings of plasma membrane or thylakoid infoldings( photosynthesis) Occurs only in intact membranes

19. Carrier Molecules Some carry both electrons & protons (H+) Cytochromes transfer electrons only Oxygen is last link of chain

20. Chemiosmosis ATP generation Proton pumps Proton motive force Protein channels with ATP synthases

21. ATP Production Protons release energy as rush through pore ATP produced via oxidative phosphorylation Damage to membrane ceases proton movement

22. Anaerobic Respiration Final electron acceptor is an inorganic molecule other than oxygen Some use NO 3 -,SO 4 2- Important in nitrogen and sulfur cycles ATP varies, less than 38 Only part of Krebs cycle & ETC used

23. Fermentation Pyruvate converted to organic product NAD+ regenerated Doesn’t require oxygen Does not use Krebs cycle or ETC –Shut down Organic molecule is final electron acceptor Produces 2 ATP max

24. Photosynthesis Conversion of light energy into chemical energy Anabolism (carbon fixation)-produce sugars from CO2 Two stages

25. Overall Reaction 6CO 2 + 6H 2 O + ATP C 6 H 12 O 6 + 6O 2 + ADP + P

26. Light Reactions Photophosphorylation-production of ATP –Only in photosynthetic cells Light energy (electromagnetic radiation) absorbed by chlorophylls –Chlorophyll a –Located in membranous thylakoids of chloroplasts- plants & algae –Infoldings of plasma membrane of cyanobacteria

27. Light Reactions Electrons flow through ETC Electron carrier is NADP+ ATP produced by chemiosmosis

28. Noncyclic Photophosphorylation Plants, algae, cyanobacteria 2 photosystems Produce both ATP via chemiosmosis Produce NADPH –Used to reduce CO 2 in dark reactions –Able to produce sugars

29. Summary ATP produced by chemiosmosis –Uses energy released in ETC Oxygen produced from splitting of water –H2O→ 2H + +2 e + O –Replace electrons lost from chlorophyll NADPH produced in second photosystem

30. Dark Reactions Calvin-Benson Cycle Requires no light Uses energy from ATP (light reactions) to reduce CO 2 to sugars Carbon fixation

31. Summary Light H 2 0 CO 2 Photosystems & ETC Chlorophyll a Chemiosmosis Calvin Cycle NADP + ADP+ P ATP NADPH O2 sugars Cellular respiration Organic cpds