山大生化历年大题

2006——2007学年第1学期1、影响酶促反应速度的因素有哪些，简述它们的作用（7分）2、简述乳酸在肝脏生成葡萄糖和糖原的基本过程。

（7分）3、说明脂肪酸彻底氧化为CO2和H2O及生成ATP的过程（12分）4、简述血氨的来源和去路。

（7分）。

5、简述胆色素的生成及正常代谢过程。

（7分）1、影响酶促反应速度的因素有哪些，简述它们的作用（7分）底物浓度、酶浓度、pH、温度、抑制剂、激活剂（抑制剂2分，其他各1分）2．乳酸在乳酸脱氢酶催化下转变为丙酮酸（1分），在线粒体丙酮酸羧化酶作用下转变为草酰乙酸（1分），再转变成苹果酸（1分）。

以苹果酸形式或天冬氨酸形式透出线粒体转至胞液再氧化或转氨生成草酰乙酸（2分）,草酰乙酸在PEP羧激酶作用下转变为PEP（1分），果糖-1,6-双磷酸在果糖双磷酸酶-1的作用下转变为F-6-P（1分）再转变成G-6-P（1分），在葡萄糖-6-磷酸酶作用下分解成葡萄糖（2分）。

F-6-P或转变成G-6-P，转变为G-1-P、UDPG后，再合成糖原（2分）。

3、说明脂肪酸彻底氧化为CO2和H2O及生成ATP的基本过程（12分）乙酰化（1分），进入线粒体（1分），β氧化（4分），三羧酸循环（3分），，呼吸链及ATP 的生成（3分）4、简述血氨的来源和去路。

（7分）。

来源（3分），去路（4分，其中尿素生成2分）5．胆红素的生成：胆红素是血红素的代谢产物。

血红素在血红素加氧酶的催化下，释放出CO，形成胆绿素。

胆绿素胆绿素还原酶的催化下，还原生成胆红素（3分）。

胆红素在血液中主要与清蛋白的结合而运输（1分）。

血中胆红素可被肝细胞表面特异受体摄入肝细胞，与胞浆中的两种载体蛋白形成复合物，进入内质网。

在葡萄糖醛酸基转移酶的催化下，生成葡萄糖醛酸胆红素(又称结合胆红素)。

结合胆红素水溶性强，毒性低，可随胆汁排入小肠（3分）。

入肠道在肠菌的作用下，脱去葡萄糖醛酸基，还原成胆素原。

胆素原在肠道下段接触空气氧化成相应的尿胆素、粪胆素，通过粪便排出体外（3分）。

肠道中约10%-20%的胆素原可被肠道吸收经门静脉入肝，大部分再随胆汁排入肠道（2分），少量经血液入肾随尿排出，再被氧化成胆素（1分），胆素呈黄褐色，是粪便和尿的主要颜色（1分）。

2006——2007学年第2学期1.The glucose can be completely degradated to CO2 and H2O in aerobic oxidation, explainthat main processes and reactions involved. (Please write the main processes and key enzymes. )in cytosol, glycolysis pathway 3 key steps, 2 pyruvate;(4)enter mito and oxidative decarboxylation 2 acetyl CoA; (2) enter TAC, 3 key steps 2CO2 and 3NADH, 1 FADH2, enter respiratory chain form H2O and ATP(4)2．To illustrate the physiological meanings of zymogen and zymogen activation, and describe mechanism by which the zymogen could be activated. Please give one example. zymogen, protect secrete tissue and as enzyme storage form, zymogen activation, (2)give physiological effect in suitable site and condition(2), trypsin and coagulation factor (2)3. To describe the major physiological function and metabolic processes of the very low density lipoprotein (VLDL). 8 markstransport for endogenetic triglyceride and cholesterol from liver(2), in liver TG ,CH andapoB100,E to form VLDL(1), get apo C,E from HDL, apo C II (1) activate LPL in blood capillary and breakdown the TG to FFA to use,(2) remove apoC and PL, CH, to IDL, liver takeIDL(B100,E)by LRP, IDL breakdown and to LDL(B100) (2)4．To describe the oxidative processes by which fatty acids are completely degradated to CO2 and H2O, and release of energy as ATP.FA activation form acyl-CoA reaction(2); enter into mito, carnitine acyl transferase;(2)βoxidation 4 steps, form acetyl CoA(2); enter TAC ; NADH and FADH2 enter 2 res.(2) chain produce 3 or 2 ATP.(2)5．Briefly illustrate four kinds of metabolic fate of pyruvate.Gluconeogenesis: glucose (2)Oxidation: H2O + CO2 (1)FA synthesis (2)Transamination: Ala (1)Ch synthesisLactate2006——2007学年第2学期B卷1.What’s the significance s of Km value and Vmax?2. 1 mol palmitic acid （18：0）is oxidized to CO2 and H2O completely, how many mols ofATP are formed？Describe the main reactions and enzymes involved in this processes. 3.How is aspartate converted to glucose and glycogen? Pleasewrite the main processes and key enzymes.4. Describe the structural features of α-helix and β-pleated sheet in proteins.5. Describe the major physiological function and metabolic processes of very low density lipoprotein (VLDL).1. 6 marksV o = 1/2 Vmax , Km = [S] , the units of Km are the concentration of S, usually Molarity (1); Km can be a measure of the affinity of E for S, The lower the value of Km, the tighter the substrate binding (2); Km is the specificity constant of a enzyme in particular condition (1); Vmax is maximal catalytic rate, The velocity of saturated all enzyme with substrate (2)2. 10 markspalmitic acid activation form acyl-CoA reaction(1); enter into mito, carnitine acyl transferase;(1)βoxidation 4 steps, form acetyl CoA(2); enter TAC(4) ; NADH and FADH2 enter 2 res. chain produce 3 or 2 ATP.(2) ,total ATP production: 146 (2)3. 10 marksTransamination: aspartate →oxaloacetate (2)Gluconeogenesis: oxaloacetate →G-6-P (4)G-6-P →G (2)G-6-P →Gn (2)4. 6 marksright handed helix. (1); 3.6 amino acid residues per turn,0.54 nm picth (1); amide hydrogen(NH) bonded 4th carbonyl oxygen(CO) to form a hydrogen bond which run parallel to the backbone and fix the structure to a rigid rod shape. (1) The R-groups outward from the helixa single pass of the polypeptide, side-by-side strands form "sheet", almost fully extended. (1);H-bonds between neighboring polypeptide chains (1); R groups are perpendicular to the backbone. parallel (strands in same direction) or anti-parallel (strands in opposite direction) (1)5. 8 markstransport for endogenetic triglyceride and cholesterol from liver(2), in liver TG ,CH andapoB100,E to form VLDL(1), get apo C,E from HDL, apo C II (1) activate LPL in blood capillary and breakdown the TG to FFA to use,(2) remove apoC and PL, CH, to IDL, liver takeIDL(B100,E)by LRP, IDL breakdown and to LDL(B100) (2)2007——2008学年第1 学期1．Please describe briefly the mechanisms of zymogen activation and physiological significances of zymogen activation.2．Please describe briefly the pathway of gluconeogenesis from lactate to glucose.3．What kinds of lipoproteins are classified according to their densities? Please describe their functions briefly.4．Please describe briefly the pathway from Ala to CO2, H2O, ATP and urea.5．Please describe the normal metabolism of bile pigments. What are the metabolic changes of bile pigments in hepatocellular jaundice?2007——2008学年第1学期B卷1.简述丙氨酸转变成葡萄糖的过程。