1. Last Lecture….. Proteins Carbohydrates Enzymes

2. Study Guide Use study guide to determine what you need to know. 95% of test will be from study guide. Do I need to know that glucose + glucose =maltose? Study guide says recognize structures list functions of carbohydrates give characteristics and where found in cell Do selected study questions only. If it was mentioned in lab/lecture and is in the study questions then it has a higher probability of being on a test.

3. Carbohydrate - Monosaccharide 3. Is this a protein? lipid? nucleic acid? carbohydrate?

4. 13. Understand protein structure and how it relates to function. Explain how amylase structure relates to its function. Amylase is an enzyme that digests starch but not cellulose. Primary structure (amino acid sequence) determines the secondary and tertiary structure. Secondary structure - sections of peptide chain coil or fold into either a lpha helices or beta sheets. Tertiary structure is extremely important to the functioning of amylase. The tertiary structure is formed by the whole peptide chain (protein) folding and coiling around itself. This forms the active site (binding site) of the enzyme. The enzyme is held in a specific configuration (tertiary structure) by H-bonding, sulfide bridges, and non-polar/non-polar interactions. In order for amylase to break down starch it must bind the starch. It can only bind starch because its tertiary structure results in the formation of a binding site. Quaternary structure would be more than one peptide chain associated with each other to form a functioning protein, but amylase is just one peptide chain.

5. 14.Characteristics of Enzymes Biological catalysts Proteins (usually) Names end in –ase Can be classified according to job they do Interactions with substrates can be described using four terms Specificity – binding site designed for one type of ligand When two or more ligands compete for the same site one may have a higher affinity than the other. The ligand with the highest affinity will bind to the protein stronger. If the protein is 50% saturated then half of the binding sites are filled. When an enzyme is 100% saturated the rate of reaction is at maximum.

6. Saturation (FOX fig 4.6) This is at a fixed amount of enzyme

7. Functions of Carbohydrates Fuel Signaling Molecule Ribose is component of: DNA RNA ATP NAD/FADH Digestive Regulation Fibers normalize transit time Fibers decreases cholesterol, TAG and LDL

8. Chapters 4 and 5 Metabolism

9. All the chemical reactions in the body Specifically those that involve energy transformations First Law of Thermodynamics energy can not be created or destroyed Second Law of Thermodynamics without the input of energy, disorder increases

10. Metabolism catabolism reactions that break things down exergonic releases energy anabolism reactions build things up endergonic takes energy

11. Oxidized electron Carriers (NAD +, FAD) Electron Transport and Oxidative Phosphorylation LipidsPolysaccharidesNucleic Acids Monosaccharides Glucose Amino AcidsNucleotidesGlycerolFatty Acids Proteins Glyceraldehyde- 3-phosphate Pyruvate Acetyl-CoA Krebs Cycle Glycolysis Reduced Electron Carriers NADH, FADH 2 ATP ADP O2O2 H2OH2O CO 2 e-e- e-e- NH 3

12. Energy Transformations (FOX 4.13) ATP

13. ATP = adenosine triphosphate spending money (paper money) universal energy carrier This is a reversible reaction.

14. ATP

15. Cell respiration glycolysis krebs cycle (citric acid cycle) electron transport chain (ETC) oxidative phosphorylation

16. Glycolysis Substrates: glucose (C 6 H 12 O 6 ) + 2ADP + 2Pi + 2 NAD Products: 2 pyruvate + 2ATP + 2 NADH Glycolysis occurs in the cytoplasm First step of glycolysis: takes energy traps glucose in the cell example of substrate level phosphorylation

17. First steps take energy (FOX fig 5.1)

18. Substrate level phosphorylation Phosphate group transferred from ATP to another molecule. Catalyzed by kinase Kinases add phosphate group to a molecule. Reverse reaction catalyzed by phosphatase

19. Glycolysis

20. FOX fig 5.6

21. Krebs Cycle (FOX fig 5.8)

22. Krebs Cycle

23. Substrates: acetyl CoA (two carbon molecule attached to coenzyme) Products: CO 2 + NADH + FADH 2 + ATP Krebs cycle occurs in the mitochondrial matrix

24. FADHmade from riboflavin (FOX fig 4.17)

25. NAD made from Niacin (FOX fig 4.17)

26. Electron Transport and Oxidative Phosphorylation

27. ETC and Oxidative Phosphorylation Located in the inner mitochondrial membrane. Energy stored in NADH and FADH 2 used to create a concentration gradient. Proton concentration higher in intermembrane space. Protons flow through ATP synthase and ATP is made. ATP made this way is called oxidative phosporylation (vs substrate level phosphorylation) What if protein pores let H + through?

28. What if no oxygen? Oxygen not available to accept electrons. Electron carriers all fill up (saturated). ETC stops. So no way to oxidize (regenerate) FADH and NAD so Krebs stops. There is a reaction that will regenerate NAD (next slide) This is called anaerobic respiration

29. Credit card use. (FOX fig 5.3)

30. Anaerobic Respiration Good news glycolysis continues Bad news two ATP per glucose lactic acid build up (pain, fatigue – chpt 12) oxygen debt must be repaid – cori cycle

31. Cori Cycle (FOX fig 5.5)

32. Burning other fuel sources Carbohydrates Proteins Lipids

33. Oxidized electron Carriers (NAD +, FAD) Electron Transport and Oxidative Phosphorylation LipidsPolysaccharidesNucleic Acids Monosaccharides Glucose Amino AcidsNucleotidesGlycerolFatty Acids Proteins Glyceraldehyde- 3-phosphate Pyruvate Acetyl-CoA Krebs Cycle Glycolysis Reduced Electron Carriers NADH, FADH 2 ATP ADP O2O2 H2OH2O CO 2 e-e- e-e- NH 3

34. Burning other fuel sources Carbohydrates glucose C6 glycolysis – 2 pyruvates and 2 ATP and 2 NADH complete cell respiration – 30 ATP 5 ATP per carbon Lipids fatty acids – C16 beta oxidation – NADH and 8 Acetyl CoA complete cell respiration – 108 ATP 6.75 ATP per carbon

35. Fuels sources of select Organs Fox Table 5.3