CH 112 STUDY GUIDE: EXAM 2

For the first examination, you should be able to:

1. Define a lipid

2. Draw and name common fatty acids

3. Draw/explain the structure of glycerol, triacylglycerides, and glycerophospholipids

4. Differentiate between single chain and double chain amphiphiles

5. Describe the properties of micelles and bilayers

6. Explain  the structure of an amino acid and a polypeptide.

7. Explain the origin of secondary structure (alpha helices, beta sheets) and tertiary structure in a protein.

8. Explain the Central Dogma of Biology.

9. Explain the differences between DNA replication, DNA transcription, and RNA translation.

10. Given a dsDNA structure, and which strand is the template strand, determine the amino acid sequence of the protein derived from transcription of the DNA.

11. Define a gene

12. Predict the probable effect of a mutation in the DNA on the resulting protein's structure AND function.

13. Draw the structures of glucose and fructose, glycerol and its derivatives, pyruvate, lactate, ATP, ADP, AMP (abbreviated adenosine as A).

14. Explain the overall functions of glycolysis, gluconeogenesis, glycogenolysis, glycogen synthesis, pyruvate dehydrogenase, the Cori cycle, the Kreb's cycle, and electron transport.

15. For selected steps in glycolysis, gluconeogenesis, glycogenolysis, glycogen synthesis, pyruvate dehydrogenase, and the Kreb's cycle, explain the type(s) of reaction(s), the expected DG^o, whether the reaction is a likely step for regulation, and a rationale for the existence of the step.

16. Identify in the above pathways all high energy compounds and vitamin derivatives.

17. Show, using chemical structures and explain verbally, how anaerobic metabolism of glucose will be slowed in the muscle unless NAD⁺ can be regenerated by lactate dehydrogenase.

18. Explain how in respiring muscle, pyruvate goes to lactate, but in the liver, lactate goes to pyruvate.

19. Describe how dietary starch, glycogen, sucrose, lactose, and fructose enters the glycolytic pathways of cells.

20. Explain the differences in dietary glycogen metabolism by salivary and pancreatic amylase and stored glycogen by glycogen phosphorylase, and rationalize the difference.

21. Identify and explain which reactions in opposing pathways must be catalyzed by different enzyme(s).

22. Explain how two opposing pathways, such as glycolysis and gluconeogenesis, and glycogenolysis and glycogen synthesis, can both be favored in the cell (from a DG perspective), but only one of the competing pathways actually predominates under a given set of conditions.

23. Explain how enzyme activity can be regulated by competitive inhibitors, allosteric inhibitors and activators, and covalent modification (phosphorylation and dephosphorylation).

24. Explain the differential allosteric regulation of phosphofructokinase and fructose 1,6-bisphosphatase by ATP, and AMP.

25. Explain possible methods of signal transduction utilized by cells.

26. Explain the cascade of events leading to the activation or inhibition of glycogen phosphorylase and glycogen synthase in liver and muscle, and how they are mediated by the hormones epinephrine and glucagon.

27. Explain the effect of insulin/glucagon on glucose and glycogen metabolism.

28. Explain the different metabolic roles of the liver and muscle in carbohydrate metabolism.

29. Explain the general role of vitamin-derivatives from vitamins such as niacin and riboflavin.

30. Explain why under anaerobic condition that pyruvate is converted to lactate in the muscle.

31. Explain the fate of NADH under anerobic and aerobic conditions.

32. Explain where the energy comes from in glycolysis, the Krebs cycle, and ox-phos. to drive the synthesis of ATP from ADP and Pi, which has a DG^o = + 7.5 kcal/mol

33. Draw the straight chain and cyclic forms of D-ribose, D-glucose, D-mannose, D-galactose.

34. Differentiate between alpha and beta forms of dissacharides and polysaccharides.