Why do you think glutathione occurs in a concentration as high as glucose? 2.Explain why glutathione must be transported from cytosol to mitochondria. 3.Explain why glutathione can confer therapeutic benefit when taken orally.

2. In contrast to the toxicity of 2-fluoro-citrate, L-(2-fluoro-)succinate is not an inhibitor of succinate dehydrogenase and the product 2-fluoro-fumarate is converted by fumarate hydratase to L-(2-fluoro-2- hydroxy)malate that breaks down to oxaloacetate. (a) the FAD coenzyme of succinate dehydrogenase as the normal substrate? Write the reaction with structural formulas to illustrate your answer. Does the oxidation of 2-fluoro-succinate yield the same number of reducing equivalents to (b) droxy)malate, which breaks down spontaneously to oxaloacetate. Write the equation with structural formulas. 2-fluoro-fumarate is a substrate of fumarate hydratase forming only L-(2-fluoro-2-hy- Oxaloacetate has been shown to be a very po- (c) tent inhibitor of succinate dehydrogenase. For the enzyme 3 isolated from cardiac muscle the Kj value is ~4 x 10-6M, as shown in the L-B plot on the right. Yet, this inhibition is never discussed in biochemistry textbooks. From your reading in the textbook,…

1.A blood test returns elevated aspartate aminotransferase levels. You suspect that the patient has suffered a heart attack. What other serum enzyme level of the ones listed should be tested to confirm the diagnosis? A.acid phosphatase B.lysozyme C.amylase D.alkaline phosphatase E.creatine kinase     2.A blood test returns elevated acid phosphatase levels. What disease(s) is indicated by this test result?   select all that apply A.mumps B.bone disease C.prostate cancer D.heart attack E.hepatitis

13. What is the consequence of complete inhibition of all mutases in liver cells? A. Liver cannot provide free glucose to maintain blood glucose levels B. Glycogen synthesis is disrupted C. Glycerol cannot be converted to glucose D. The only fate of glucose-6-phosphate is to be converted to fructose-6-phosphate

29. Labels. Suppose that you had an in vitro fatty acid- synthesizing system that had all of the enzymes and cofactors required for fatty acid synthesis except for acetyl CoA. To this system, you added acetyl CoA that contained radioactive hydrogen (³H, tritium) and carbon 14 (¹4C) as shown here. 3H O 14 3H-C-C SCOA 3H The ratio of ³H/¹4C is 3. What would the ³H/14C ratio be after the synthesis of palmitic acid (C₁6) with the use of the radioactive acetyl CoA?

3. Acetylcholinesterase is a serine hydrolase enzyme im- portant in nerve signal transmission, hydrolyzing acetylcho- line, an ester molecule with a positively charged quaternary nitrogen group. The structure of the physiologically relevant substrate of this enzyme is shown on the right. The quater- H₂C nary nitrogen group serves to anchor the molecule in the active site Gly121 Oxy- anion hole Gly122 Ala204 Substrate ACh His447 Catalytic triad Ser203 Glu202 Glu334 Ser229 CH3 N+ CH3 CH3 The a Scale document down rine protease family, consisting of a catalytic triad Ser203- His447-Glu334 with Ser203 supplying the nucleophilic hydroxyl group and an oxyanion hole com- prised of peptide NH groups of Gly121, Gly122, and Ala204, illustrated in the diagram above, for which carbon (green), nitrogen (blue), and oxygen (red) atoms are shown while hydrogen atoms are white. The enzyme catalyzed reaction can be represented by the following scheme: (a)( k1 K2 E + S = ES K-1 K3 EYE + P where ES…

1. What are the steps that Aconitase facilitates in changing Citrate to Isocitrate? 2. What does the residue Histidene 101 do as Aconitase catalyzes the change of Citrate to Cis-aconitate ? 3. What does the residue Serine 642 do as Aconitase catalyzes the change of Citrate to Cis-aconitate

1.a. Given what you know about glycolysis and gluconeogenesis, does it make sense that insulin activates PDH phosphatase? Why? b.How do vitamins increase to the breadth of chemical reactions available within a biological system?

2. What is the chemical reaction that lactase catalyzes? Write it below in word form as well as in its chemical equation.

III. Match the item to each step in the Krebs Cycle. a. isocitrate f. oxaloacetate g. sulfur h. a-ketoglutarate i. fumarate j. ATP b. succinate C NAD d. malate e. succinyl-CoA 85. What molecule is formed when GTP is oxidized to form GDP? 86. What molecule is formed when FAD is reduced? 87. Which molecule must be reduced so that oxaloacetate is formed? IV. Match each compound to a step that of the Light-Dependent Reaction. a. P700 b. P680 . P680 d. ATP synthase e. PhotosystemI f. electron acceptor g. electron carrier h. chlorophyll II. i. NADPH reductase j. b. - f complex 88. Light photons excite electrons from this part of the Reaction Centre. 89. The enzyme that helps remove electrons from the thylakoid. 90. The enzyme that acts to form ATP with chemiosmosis. V. Match the enzyme or protein to the replication process. a. DNA polymerase l b. DNA polymerase I| . DNA polymerase III d. primase e. DNA ligase f. helicase g. single-strand-binding proteins h. topoisomerase Il 91. Unwinds helix…