<4d6963726f736f667420576f7264202d203936bad3a468a44abec7a6d2c2e5a475a8745fa5cdaaaba4c6bec75f2e646f63>

中原大學 96 學年度碩士班入學考試 96 年 3 月 25 日 16:00~17:30 生物醫學工程系 誠實是我們珍視的美德， 我們喜愛「拒絕作弊，堅守正直」的你！ 科目： 生物化學 （共 3 頁第 1 頁） ■可使用計算機，惟僅限不具可程式及多重記憶者 □不可使用計算機 1. Describe the reactions of the citric acid cycle, including the substrate, enzyme and product for each 2. Describe the evolutionary hypothesis of photosynthetic eukaryotes. (4%) 3. A buffer contains 0.01 mol of lactic acid (pKa = 3.86) and 0.05 mol of sodium lactate per liter. (1) Calculate the pH of the buffer. (2%) (2) Calculate the change in pH when 5 mL of 0.5 M HCl is added to 1 L of the buffer. (4%) (3) Calculate the pH if you added the same quantity of HCl to a solution containing 0.12 mol/L of 4. A nonapeptide was determined to have the following amino acid composition: (Lys)2, (Gly)2, (Tyr)2, His, Leu, Met. The native peptide was incubated with 1-fluoro-2,4-dinitrobenzene (FDNB) and then hydrolyzed; 2,4-dinitrophenylhistidine was identified by HPLC. When the native peptide was exposed to cyanogen bromide (CNBr), and octapeptide and free glycine were recovered. Incubation of the native peptide with trypsin gave a pentapeptide, a tripeptide, and a free Lys. 2,4-Dinitrophenylhsitidine was recovered from the pentapeptide, and 2,4-dinitrophenyltyrosine was recovered fro the tripeptide. Digestion with pepsin produced a dipeptide, a tripeptide, and a tetrapeptide. The tetrapeptide was composed of (Lys)2, Tyr, and Gly. Cleavage points on either the carbonyl (C) or the amino (N) side of the indicated amino acid residues (1) Deduce the sequence of the complete polypeptide from the information above. (5%) (2) What are the products after digestion the complete polypeptide with chymotrypsin? (3%) (3) What is the estimated molecular weight of the complete polypeptide? (2%) (4) What is the length of ORF (open reading frame) for the complete polypeptide? (2%) 5. Describe the procedure of site-directed mutagenesis. (6%) 6. Answer the following questions: (2% for each) (1) The smallest amino acid? ___________ (2) The amino acid has atypical amino acid structure? __________ (3) The amino acid is able to form disulfide bond? _____________ (4) Secondary structure of silk fibroin? ___________ (5) The protein that interacts with partially folded or improperly folded polypeptides to facilitate correct folding pathway? ________________ (6) A misfolded protein that causes Mad Cow disease? ___________ (7) A procedure to determine the isoelectric point of a protein? _____________ (8) The molecular structure within the antigen where the antibody binds? ___________ (9) The immunoglobulin plays an important role in the allergic response? ___________ (10) The component of bacterial cell wall? ___________ (11) The structural component of plant cell wall? ___________ (12) The structural component of insect exoskeleton? ____________ (13) The protein receptor that binds carbohydrates with high affinity and specificity? __________ (14) An inactive precursor of an enzyme? ___________ (15) RNA molecules with enzyme activities? __________ 7. The enzyme, cyclooxygenase, uses oxygen to convert arachidonic acid to prostaglandins. The reaction is inhibited by ibuprofen. The kinetic data given below are for the reaction catalyzed by (1) Write down “Lineweaver-Burk equation”. (2%) (2) Calculate Vmax and Km for the enzyme without adding ibuprofen. (4%) (3) Calculate Vmax and Km for the enzyme after adding ibuprofen. (4%) (4) Determine the type of inhibition that ibuprofen exerts. (2%) 8. Match the following molecules with their biological roles. (1% for each) a. ________ serve as lubricants in the synovial fluid of joints b. ________ overproduction will cause asthmatic attacks c. ________ antioxidant that prevents oxidative damage to the f. ________ sphingolipids containing complex oligosaccharides as head groups; especially common in nervous tissue g. ________ derivative of archidonic acid that involves in platelet h. _________ regulate calcium uptake in the intestine and calcium i. _________ binding to antithrombin to inhibit blood coagulation j. _________ protein that targets an intracellular protein for degradation k. _________ the hormone signals the liver to produce and release more

Source: http://www3.lib.cycu.edu.tw/exams_new/master/mbe/96/mbe96203.pdf