Download A mutant defective in enzyme

國立彰化師範大學九十四學年度碩士班招生考試試題
系所：生物技術研究所
科目： 生物化學
☆☆請在答案紙上作答☆☆
共 6 頁，第 1 頁
一、選擇題（each 2%）
1. The sugar that forms a major component of nucleic acids (DNA, RNA) is
(a)Fructose
(b)Galactose
(c)Ribose
(d)Sucrose
2. The enzyme that joins DNA fragments cut by restriction enzymes is called:
(a)Primase
(b)Polymerase
(c)Ligase
(d)DNA phosphorylase
3. The two features of the tRNA molecule involved in converting the triplet codon to an amino acid are:
(a)in the anticodon loop and the 3'CCA end
(b)in the anticodon loop and the D stem
(c)solely in the anticodon loop
(d)solely at the 3'CCA end
4. All the following are common properties of enzymes except:
(a) their active sites contain large hydrophobic pockets.
(b) they usually bind their substrates through multiple weak noncovalent interactions.
(c) they exhibit saturation kinetics at high substrate concentrations.
(e)they have a high degree of substrate and product specificity.
5. How do enzymes work to accelerate a chemical reaction?
(a)They raise the average energy of the reactants
(b)They provide a means of acceleration by being completely consumed in the reaction
(c)They lower the activation energy
(d)They raise the average energy of the products
(e)They raise the activation energy
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國立彰化師範大學九十四學年度碩士班招生考試試題
系所：生物技術研究所
科目： 生物化學
☆☆請在答案紙上作答☆☆
共 6 頁，第 2 頁
6. One of the primary reasons that DNA is a more chemically stable compound than RNA is:
(a)RNA has a 2' hydroxyl group
(b)DNA contains thymine instead of uracil
(c)Nucleotides can only be added to the 3' hydroxyl in a DNA chain
(d)RNA has a 5' phosphate group
(e)DNA is modified by the addition of bases at the 1' carbon
7. What would be the primary effect of a genetic disease that destroyed the cooperative binding of oxygen by
hemoglobin?
(a)Decrease in oxygen binding to hemoglobin
(b)Decrease in CO2 binding to hemoglobin
(c)Decrease in the oxygen pressure in the lungs
(d)Decrease in the efficiency of oxygen transport by hemoglobin
(e)Rickets
8. All of the following are mechanisms by which an enzyme may be regulated, except:
(a) allosteric interactions.
(b) proteolytic cleavage of an inactiver precursor.
(c) control of enzyme degradation.
(d) disulfide linkage to a regulatory protein.
9. Enzymes differ from chemical catalysts in that enzyme catalysis do NOT involve:
(a) high specificity.
(b) physiological pH.
(c) side reactions.
(d) regulation.
10. Enzymes increase the reaction rate by decreasing the:
(a) activation energy.
(b) G.
(c) kinetic stability.
(d) Keq.
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國立彰化師範大學九十四學年度碩士班招生考試試題
系所：生物技術研究所
科目： 生物化學
☆☆請在答案紙上作答☆☆
共 6 頁，第 3 頁
11. The generation of the membrane potential in most cells results in large part from which of the following?
(a) Relatively high [K+] inside the cell and high [Na+] outside the cell, with greater permeability of the
membrane to K+ than Na+.
(b) Relatively high [K+] inside the cell and high [Na+] outside the cell, with greater permeability of the
membrane to Na+ than K+.
+
+
(c) Relatively high [K ] outside the cell and high [Na ] inside the cell, with greater permeability of the
membrane to K+ than Na+.
(d) Relatively high [K+] outside the cell and high [Na+] inside the cell, with greater permeability of the
membrane to Na+ than K+.
(e) Rubbing the cells together so they build up static charge.
12. Within a layer of phospholipid molecules in a cell, which part of the lipid molecule faces the cytoplasm?
(a) the phosphorylated head group
(b) the hydrocarbon tails
(c) both head and tail because the molecules lie sideways
(d) neither; the phospholipids dissolve in water and disperse
(e) the fatty acids
13. Which of the following statements best describes how a pore may be formed that passes through the membrane
to form a pore or a channel?
(a) Several membrane-spanning helices associate to form a central pore
(b) A single helix passes the membrane with hydrophobic amino acid side chains residues at all positions
(c) Pores are usually formed by the tight packing of cholesterol into rigid structures
(d) Pores that form ion channels are most often comprised of beta sheet structures that form beta barrels
14. Which method cannot be used for detecting and analyzing protein-protein interaction ?
(a) Affinity chromatography.
(b) Immunoprecipitation.
(c) Biosensor analysis, use an instrument name BIACORE.
(d) Yeast two hybrid system.
(e) Western blot analysis.
15. Choose the pathway which the lipoic acid involve:
(a) Glycolysis.
(b) The Krebs cycle.
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國立彰化師範大學九十四學年度碩士班招生考試試題
系所：生物技術研究所
科目： 生物化學
☆☆請在答案紙上作答☆☆
共 6 頁，第 4 頁
(c) Electron transport chain
(d) Lactic acid fermentation.
(e) Alcoholic fermentation.
16. Which reaction does NOT locate within mitochondria?
(a) Citric acid cycle.
(b) Fatty acid oxidation.
(c) Amino acid catabolism.
(d) Pyruvate oxidation.
(e) Lipid synthesis.
17. Which product in glycolysis also involve in glycoprotein synthesis?
(a) G6P.
(b) F6P.
(c) FBP.
(d) G3P.
(e) Pyruvate.
18. The phosphofructokinase reaction is the primary step at which glycolysis is regulated. Which of the
following can inhibit its activity?
(a) Pyruvate.
(b) Phosphoenolpyruvate.
(c) Citrate.
(d) Succinate.
(e) ADP.
19. Which of the following protein with half-lives less than 2 hours of degradation in protein turnover?
(a) Histones.
(b) Pyruvate carboxylase.
(c) Acetyl-CoA carboxylase.
(d) Protein kinase C
(e) Hemoglobin
20. Which of the following is NOT true that the entry points into the citric acid cycle for the breakdown
products of the amino acids?
(a) Alanine to pyruvate.
(b) Tryptophan to acetyl-CoA.
(c) Glutamine to fumarate.
(d) Methionine to succinate.
(e) Arginine to α-ketoglutarate.
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國立彰化師範大學九十四學年度碩士班招生考試試題
系所：生物技術研究所
科目： 生物化學
☆☆請在答案紙上作答☆☆
共 6 頁，第 5 頁
21. Which of the following statement was NOT correct?
(a) Mammalian glycoproteins are classified as O-linked or N-linked.
(b) N-linked glycoproteins contains an N-acetylglucosamine.
(c) N-linked glycoproteins contains an asparagine residue in the protein.
(d) O-linked glycoproteins contains an N-acetylgalactosamine.
(e) O-linked glycoproteins contains a serine or tyrosine residue in the protein.
(f) The A, B, O blood group substances found on erythrocyte surface are belong to O-linked
glycoproteins.
22. Which of the following statement was NOT true?
(a) G6P inhibits glycolysis.
(b) Alanine inhibits glycolysis.
(c) AMP inhibits glycolysis.
(d) Acetyl-CoA inhibits glycolysis.
(e) Citrate inhibits glycolysis.
23. The location of following enzymes involved in urea cycle, which is NOT correct?
(a) Arginase in cytosol.
(b) Argininosuccinate syhthetase in cytosol.
(c) Argininosuccinase in mitochondria.
(d) Ornithine transcarbamoylase in mitochondria.
(e) Carbamoyl phosphate synthetase in mitochondria.
二、問答題(54 %)
1. Muscle protein responds to conditions such as starvation, trauma, burns and septicemia, by
undergoing massive degradation. Of the amino acids released, most important as a source of fuel are
branched-chain amino acids? What are they? (3 %)What enzyme involved in the first step in their
degradation? (2 %)
2. Tumor cells treated with hydroxyurea show a specific inhibition of DNA synethesis with little or no
inhibiton of RNA or protein synthesis. Why? (5 %)
3. The sense of smell, or olfaction, is done by olfactory neurons. Each olfactory neuron expresses only
one type of receptor. How do these receptors work? (5 %)
4. Heparin is an antithrombotic drug. How dose it work? (5%)
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國立彰化師範大學九十四學年度碩士班招生考試試題
系所：生物技術研究所
科目： 生物化學
☆☆請在答案紙上作答☆☆
共 6 頁，第 6 頁
5. The lumen of the stomach is highly acidic (pH=1). How do gastric parietal cells in the lumen
produce acid under stimuli such as histamine and gastrin? (10 %)
6. How do peripheral membrane proteins associate with the membrane ?(4 %)
7. Describe TWO features/characteristics/properties of signal sequences that target proteins to various
intracellular organelles. (8 %) (Any TWO)
8. What happened when muscle cell received the epinephrine signal? Please describe the signal
transduction pathway in detail.(8 %)
9.
A mutant defective
in enzyme
1
2
3
4
Accumulates
metabolite
Requires an
external source
of
A
B
C
D
D, or E
E
C, D, or E
B, C, D, or E
Allows the growth of
another mutant,
defective in enzyme
1 or 2
1, 2, or 3
1
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There are five products (A, B, C, D, E) and four enzymes (1, 2, 3, 4) involved in the arginine
biosynthetic pathway of the bread mold N. crassa, a student used mutations as biochemical probe to
study the pathway, please order the products and enzymes according to the table list above.(4 %)
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