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【已刪除】108年 - 學士後西醫生物-108#81852

科目：學士後西醫-生物學 | 年份：108年 | 選擇題數：90 | 申論題數：0

試卷資訊

所屬科目：學士後西醫-生物學

選擇題 (90)

【已刪除】1. If a long-day plant has a critical night length of 10 hours, which of the 24-hour cycles would prevent flowering? (A) 16 hours light/8 hours dark (B) 13 hours light/11 hours dark (C) 15 hours light/9 hours dark (D) 4 hours light/8 hours dark/4 hours light/8 hours dark (E) 8 hours light/8 hours dark/light flash/8 hours dark
【已刪除】2. Which of the following species is most likely to be a candidate for geographical isolation? (A) bat (B) land snail (C) squirrel (D) salt-water fish (E) sparrow
【已刪除】3. Which of the following characteristics adds most to vertebrate success in terrestrial environments? (A) the amniotic egg (B) the ability to maintain a constant body temperature (C) two pairs of appendages (D) claws (E) a four-chambered heart
【已刪除】4. Which of the following statements is not true for the prophase I of meiosis? (A) Homologous chromosomes are pairing. (B) Each homologous chromosome consists of two sister chromatids. (C) Each chromosome consists of single strand of DNA. (D) The pairing homologs are joined by the synaptonemal complex. (E) Chiasmata occur between non-sister chromatids.
【已刪除】5. Which cells in a plant root form a protective barrier to the vascular system where all materials must move through the symplast? (A) Cortex (B) Pericycle (C) Epidermis (D) Endodermis (E) Exodermis
【已刪除】6. What are the wavelengths of light that chlorophyll absorbs most strongly? (A) Blue and red (B) Blue and green (C) Green and yellow (D) UV and infrared (E) UV and blue
【已刪除】7. Which statement about human reproduction is correct? (A) Fertilization occurs in the uterus. (B) In humans, spermatogenesis and oogenesis function best at normal, core body temperatures. (C) A human oocyte completes meiosis after a sperm penetrates it. (D) The earliest stages of spermatogenesis are found closest to the lumen of the seminiferous tubule. (E) Sertoli cells produce testosterone under FSH stimulation.
【已刪除】8. Which of the following hormones is the most useful for promoting the growth of the root after plant cuttings? (A) Abscisic acid (B) Auxins (C) Cytokinins (D) Gibberellins (E) Oligosaccharins
【已刪除】9. Given the parents TTEECc × TteeCc, assume simple dominance for each trait and independent assortment. What proportion of the progeny will be expected to phenotypically resemble the first parent (TTEECc)? (A) 1/4 (B) 1/8 (C) 3/4 (D) 3/8 (E) 1
【已刪除】10. A genetic change that caused a certain Hox gene to be expressed along the tip of a vertebrate limb bud instead of further back made possible the evolution of the tetrapod limb. This type of change is an illustration of ________. (A) heterochrony, a change in the timing of developmental events (B) allopolyploidy, an increase in chromosome number (C) paedomorphosis, or retention of ancestral juvenile structures in an adult organism (D) a change in a homeotic developmental gene that altered the spatial organization of body parts (E) allopatric speciation
【已刪除】11. The conversion of fibrinogen to fibrin ________. (A) occurs when fibrinogen is released from broken platelets (B) occurs within red blood cells (C) is linked with hypertension and may damage artery walls (D) is likely to occur too often in an individual with hemophilia (E) is the final step of a clotting process that involves multiple clotting factors
【已刪除】12. Which of the following type of leukocyte would play a role as “antigen presenting cells” and trigger the MHC class II mediated immune response? (A) Basophils (B) Eosinophils (C) T lymphocytes (D) Macrophages (E) Neutrophils
【已刪除】13. The components of the endomembrane system of cells don’t include ________. (A) nuclear envelope (B) endoplasmic reticulum (C) vacuoles (D) plasma membrane (E) mitochondrion
【已刪除】14. Which area of the human brain contains the rhythmic breathing control center? (A) Neocortex (B) Hippocampus (C) Thalamus (D) Medulla (E) Cerebellum
【已刪除】15. ________ absorb products of photosynthesis from living host plants. (A) Epiphytes (B) Carnivorous plants (C) Xerophytes (D) Halophytes (E) Parasitic plants
【已刪除】16. An enzyme with a high turnover number has_______. (A) a low Km (B) a high kcat (C) a high Vmax (D) a high kcat/Km (E) a high Km
【已刪除】17. Which of the following descriptions for myoglobin is correct? (A) Myoglobin contains four subunits. (B) The binding of O2 with myoglobin shows cooperative kinetic. (C) O2 binds with Fe3+ of heme group in myoglobin. (D) 2,3-BPG does not affect the binding of O2 with myoglobin. (E) Myoglobin and hemoglobin are not evolutionarily related.
【已刪除】18. Which of the following parts of the IgG molecule are not involved in binding to an antigen? (A) Heavy chain (B) Light chain (C) Fab (D) Fc (E) Variable domain
【已刪除】19. Aspirin is well-known as an inhibitor of_______. (A) lipoxygenase (B) hormone sensitive lipase (C) cyclooxygenase (D) fatty acid synthase (E) acetyl-CoA carboxylase
【已刪除】20. Which is not derived from arachidonic acid? (A) lipoxin (B) prostaglandin (C) thromboxane (D) leukotriene (E) prednisone
【已刪除】21. In fatty acid synthesis, acetyl group is shuttled out of mitochondria as: (A) pyruvate (B) oxaloacetate (C) α-ketoglutarate (D) glutamine (E) citrate
【已刪除】22. Which of the metabolites in the urea cycle is linked to the citric acid cycle? (A) Citrulline (B) Argininosuccinate (C) Arginine (D) Ornithine (E) Urea
【已刪除】23. Which of the following amino acids is the crucial precursor for the biosynthesis of melatonin? (A) Phenylalanine (B) Methionine (C) Lysine (D) Tryptophan (E) Tyrosine
【已刪除】24. Which is not an electron acceptor in the mitochondrial respiratory chain? (A) FMN (B) FAD (C) Fe3+ (D) Cu2+ (E) Coenzyme A
【已刪除】25. Which is the active sugar in glycogen synthesis in animal? (A) CDP-glucose (B) GDP-glucose (C) UDP-glucose (D) Glucose 6-phosphate (E) Glucose 1-phosphate
【已刪除】26. Which of the following compounds is not a product of the enzymatic steps in the citric acid cycle? (A) Acetyl-CoA (B) α-ketoglutarate (C) Succinate (D) Fumarate (E) Malate
【已刪除】27. Gout is caused by aberrant degradation of purine, leading to accumulation of uric acid. Allopurinol inhibits_______, leading to reduce the production of uric acid. (A) purine nucleoside phosphorylase (B) xanthine oxidase (C) nucleotidase (D) urease (E) hypoxanthine-guanine phosphoribosyltransferasse
【已刪除】28. Which of the following enzymes cannot catalyze the formation of a phosphodiester bond? (A) RNA polymerase (B) DNA polymerase (C) Ligase (D) Endonuclease (E) Reverse transcriptase
【已刪除】29. Histones are found in eukaryotic cell nuclei that package and order the DNA into structural units called nucleosomes. They are usually rich in _______, and they interact with DNA via _______. (A) lysine and arginine; ionic bonds (B) glutamic acid and aspartic acid; hydrogen bonds (C) alanine and glycine; ionic bonds (D) lysine and arginine; hydrogen bonds (E) glutamic acid and aspartic acid; ionic bonds
【已刪除】30. The binding of _______ with lac repressor can activate the transcription of lac operon. (A) arabinose (B) isopropyl β-thiogalactoside (C) tryptophan (D) β-galactosidase (E) mannose
【已刪除】 31. Phenylketonuria is an autosomal recessive inheritable disease. If the incidence of the disease is about 1/10000, what is the frequency of the phenylketonuria recessive disease allele (a) and the (Aa) genotype frequency of the person carrying the recessive gene in the population? (A) 0.1% and 0.99% (B) 0.1% and 1.98% (C) 1% and 3.96% (D) 1% and 1.98% (E) 0.1% and 3.198%
【已刪除】32. Which of the following features belong to the coral? 1. a gastrovascular cavity 2. a polyp stage 3. a medusa stage 4. cnidocytes 5. a pseudocoelom (A) 1 and 4 (B) 2 and 3 (C) 2, 3, and 4 (D) 1, 2, 3, and 4 (E) all five of these
【已刪除】33. What is the correct sequence of the following steps during the human excretory system? (A) excretion → filtration → secretion → reabsorption (B) filtration → reabsorption → secretion → excretion (C) excretion → filtration → reabsorption → secretion (D) excretion → filtration → secretion (E) filtration → excretion → reabsorption → secretion
【已刪除】34. In which of the following conditions, asexual reproduction results in greater reproductive success than does sexual reproduction? (A) When pathogens are rapidly diversifying. (B) When a species has accumulated numerous deleterious mutations. (C) When there is some potential for rapid overpopulation. (D) When a species is expanding into diverse geographic settings. (E) When a species is in stable and favorable environments.
【已刪除】35. Which of the following does not tend to promote speciation? (A) The founder effect (B) Gene flow (C) Natural selection (D) Polyploidy (E) Disruptive selection
【已刪除】36. What is the response a plant would react to an attack from herbivores? (A) Leaf abscission to prevent further loss of tissue. (B) Early flowering to reproduce before being eaten. (C) Production of chemical compounds for defense or to attract predators of the herbivores. (D) Production of physical defenses, such as thorns. (E) Production of thicker bark and cuticle to make it more difficult to eat.
【已刪除】37. A healthy young man ingests a large volume of distilled water and 50 min later a study is undertaken. In which of the following parts in his kidneys would the liquid with the greatest osmolarity be found? (A) Proximal tubule (B) The bottom of the loop of Henle of the cortical nephron (C) The bottom of the loop of Henle of the juxtamedullary nephron (D) Distal tubule of the juxtamedullary nephron (E) The innermost medullary collecting duct
【已刪除】38. Which of following statements about human digestive function is incorrect? (A) When food bolus enters the stomach, gastrin is secreted into the gastric lumen. (B) Secretin released from duodenum inhibits the secretion of gastric juice. (C) CCK released from duodenum stimulates the secretion of pancreatic enzymes. (D) The vagus nerve activates the parietal cells of stomach when a bite of food enters the mouth. (E) Increased sympathetic activity would slow down the motility of digestive tract.
【已刪除】39. Which of the following statements about human respiration is true? (A) Most of the carbon dioxide in the blood is bound to hemoglobin. (B) Increased pH level decreases affinity of hemoglobin for O2 and improves the unloading reaction. (C) At normal systemic venous PO2, about 25% of the hemoglobin is in the form of oxyhemoglobin. (D) Surfactants can increase the surface tension of the lungs. (E) During an unforced exhalation, alveolar pressure is greater than atmospheric pressure.
【已刪除】40. Which event occurs after the first heart sound and before the second heart sound in human cardiac cycle? (A) Ventricular relaxation (B) Aortic systolic pressure (C) AV valves open (D) P wave of the ECG (E) Blood volume in ventricle increases
【已刪除】41. In a neuroscience lab, a student increased the concentration of K+ outside a neuron from 5 mM to 10 mM, while maintaining other ion concentrations as they were. What would happen to the neuron’s membrane potential? (A) The membrane potential would become more negative. (B) The membrane potential would become less negative. (C) The membrane potential would remain the same. (D) The membrane potential would be closer to the K+ equilibrium potential. (E) There would be no potential difference across the membrane.
【已刪除】42. Which of the following is not true about helper T cells? (A) They function in both cell-mediated and humoral immune responses. (B) They bear surface CD4 molecules. (C) They recognize polysaccharide fragments presented by infected cells. (D) They are subject to infection by HIV. (E) When activated, they secrete cytokines that stimulate other lymphocytes.
【已刪除】43. Which of the following statements about vision is not true? (A) Rods are more light-sensitive than cones and are responsible for night vision. (B) Color vision results from the presence of three subclasses of cones in the retina. (C) Perception of visual information takes place in the cerebral cortex. (D) All information from the left eye goes to the right visual cortex and all information from the right eye goes to the left visual brain. (E) The ciliary muscles relax if you look away from this page and focus your eyes on a distant object and the lens is flattened.
【已刪除】44. Which of the following sensory receptors is incorrectly paired with its category? (A) Photoreceptor — rod cell in retina (B) Nociceptor — muscle spindle (C) Chemoreceptor — taste receptor in tongue (D) Mechanoreceptor — hair cell in cochlea (E) Electroreceptor — hair cell in ampulla of Lorenzini
【已刪除】45. Within a few weeks of treatment with the drug 3TC, a patient’s HIV population consists entirely of 3TC-resistant viruses. What is the best explanation? (A) HIV has the ability to change its surface proteins and resist vaccines. (B) The patient must have become reinfected with 3TC-resistant viruses. (C) HIV began making drug-resistant versions of reverse transcriptase in response to the drug. (D) A few drug-resistant viruses were present at the start of treatment, and natural selection increased their frequency. (E) Some viruses developed drug resistance and then passed their function.
【已刪除】46. A founder event favors microevolution in the founding population mainly because ________. (A) mutations are more common in a new environment (B) a small founding population is subject to extensive sampling error in the composition of its gene pool (C) the new environment is likely to be patchy, favoring diversifying selection (D) gene flow increases (E) members of a small population tend to migrate
【已刪除】47. Which of the following descriptions are correct? 1. Green algae — closest relative of green plants 2. Brown algae — includes the largest seaweeds 3. Diatoms — examples of stramenopiles 4. Dinoflagellates — glass, two-part shells 5. Red algae — has no flagellated stages in life cycle (A) 1234 (B) 2345 (C) 1245 (D) 1235 (E) 2345
【已刪除】48. Which of the following is an example of an opportunistic pathogen that can cause a mycosis? (A) Claviceps pururea, which produces ergots on rye that can cause serious symptoms in humans if milled into flour (B) Ophiostoma ulmi, which causes Dutch elin disease (C) the ascomycetes that causes ringworm (D) Candida albicans, which causes vaginal yeast infections (E) the mold Penicillium, an ascomycete that is now grown in liquid culture to produce antibiotics
【已刪除】49. Which of the following hormones is produced by adipose cells that helps to control appetite? (A) Insulin (B) Neuropeptide Y (C) Glucagon (D) Leptin (E) Ghrelin
【已刪除】50. The high osmolarity of the renal medulla is maintained by all of the following except ________. (A) diffusion of salt from the ascending limb of the loop of Henle (B) active transport of salt from the upper region of the ascending limb (C) the spatial arrangement of juxtamedullary nephrons (D) diffusion of urea from the collecting duct (E) diffusion of salt from the descending limb of the loop of Henle
【已刪除】51. When light strikes the pigment rhodopsin in a rod cell, retinal dissociates from opsin, initiating a signal-transduction pathway that ________. (A) depolarizes the neighboring bipolar cells and initiates an action potential in a ganglion cell (B) depolarizes the rod cell, causing it to release the neurotransmitter glutamate, which excites bipolar cells (C) hyperpolarizes the rod cell, reducing its release of glutamate, which excites some bipolarcells and inhibits others (D) hyperpolarizes the rod cell, reducing its release of glutamate, which excites amacrine cells but inhibits horizontal cells (E) converts cGMP to GMP, opening sodium channels and hyperpolarizing the membrane, causing the rhodopsin to become bleached
【已刪除】52. The transduction of sound waves to action potentials takes place ________. (A) within the tectorial membrane as it is stimulated by the hair cells (B) when hair cells are bent against the tectorial membrane, causing them to depolarized and release neurotransmitter molecules that stimulate sensory neurons (C) as the basilar membrane becomes more and depolarizes, initiating an action potential in a sensory neuron (D) as the basilar membrane vibrates at different frequencies in response to the varying volume of sounds (E) within the middle ear as the vibrations are amplified by the malleus, incus, and stapes
【已刪除】53. Which one of the following hormones could raise the level of basal metabolic rate (BMR)? (A) Calcitonin (B) Thyrocalcitonin (C) Triiodothyronine (D) Dexamethasone (E) Parathyroid hormone
【已刪除】54. Which of the following amino acid and the derivative is not proved to be a neurotransmitter? (A) Glycine (B) Glutamic acid (C) Aspartic acid (D) Gamma-aminobutyric acid (E) Histamine
【已刪除】55. Which of the following chemicals from plants has been using as an indicator to measure the glomerular filtration rate (GFR) in clinical, because it cannot be re-absorbed and secreted in nephron tubules. (A) Creatinin (B) Inulin (C) Digitalis (D) Colchicine (E) Alkaloids
【已刪除】56. Which of the following statements is true? (A) In Crassulacean acid metabolism (CAM) plants, carbon fixation and the Calvin cycle occur in the same cells at different times. The Calvin cycle of CAM plants occurs during the night, so that the Calvin cycle is also named the dark reaction. (B) Pineapples are CAM plants. (C) For C4 plants, the Calvin cycle is mainly carried out in the mesophyll cells. (D) C3 plants are more resistant to drought than C4 plants. (E) Photorespiration occurs when stomata of C3 plants are fully open during the day.
【已刪除】57. Which of the following traits is shared by charophytes and land plants? (A) Alternation of generations (B) Walled spores produced in sporangia (C) Multicellular gametangia (D) Formation of phragmoplast (E) Apical meristems
【已刪除】58. Which of the following statements for characteristics of monocots and eudicots is not true? (A) Veins of monocots are usually parallel; veins of eudicots are usually netlike. (B) Stem vascular tissues of monocots are usually scattered; stem vascular tissues of eudicots are usually arranged in ring. (C) The root system of monocots are usually fibrous (no main root); taproots are usually present in the root system of eudicots. (D) There are three openings on every pollen grain of monocots; there is one opening on every pollen grain of eudicots. (E) Floral organs of monocots are usually in multiples of three; floral organs of eudicots are usually in multiples of four or five.
【已刪除】59. In the process of double fertilization, one sperm nucleus undergoes fusion with the egg nucleus and the other with the _______nuclei. (A) integument (B) polar (C) endosperm (D) funiculus (E) nucellus
【已刪除】60. Which of the following statements for cellular respiration and photorespiration is false? (A) Both of these two reactions consume O2. (B) CO2 is among the final products of these two reactions. (C) Adenosine triphosphates (ATPs) are consumed in the processes of these two reactions. (D) ATP is among the final products of these two reactions. (E) All vascular plants are able to conduct cellular respiration, while photorespiration mainly happen to C3 plants.
【已刪除】61. A mixture of four amino acids is separated by using a cation exchanger with an elution gradient of increasing NaCl solution. What is the correct elution sequence? (A) Asp, Lys, Arg, Ser (B) Asp, Ser, Lys, Arg (C) Asp, Arg, Ser, Lys (D) Ser, Asp, Arg, Lys (E) Lys, Arg, Ser, Asp
【已刪除】62. For an α-helix has the sequence : +H3N-Asp-Trp-Gln-Leu-His-Val-Phe-Ala-Lys-Val-Glu-COO- , the carbonyl oxygen (in the peptide bond) of the histidine residue is hydrogen bonded to the amide nitrogen of _______. (A) Trp (B) Lys (C) Val (D) Gln (E) Leu
【已刪除】63. The carbohydrate moiety is always attached to glycoproteins through _______. (A) aspartate, glutamate or tyrosine (B) tryptophan, glutamine or alanine (C) cysteine, phenylalanine or histidine (D) asparagine, serine or threonine (E) valine, leucine or isoleucine
【已刪除】64. Which of the backbone repeated units of polysaccharides is not correct? (A) Amylose: (α1-4) Glc (B) Dextran: (α1-6) Glc (C) Glycogen: (α1-4) Glc (D) Cellulose: (β1-4) Glc (E) Chitin: (β1-4) Glc
【已刪除】65. Taking one mole of glucose through glycolysis and the citric acid cycle generates: (A) 6 CO2, 8 NADH/H+, 1 FADH2 and 1 ATP (B) 6 CO2, 8 NADH/H+, 1 FADH2 and 2 ATP (C) 6 CO2, 8 NADH/H+, 2 FADH2 and 4 ATP (D) 6 CO2, 10 NADH/H+, 2 FADH2 and 2 ATP (E) 6 CO2, 10 NADH/H+, 2 FADH2 and 4 ATP
【已刪除】66. Which of the following is a hetero-polysaccharide? (A) Cellulose (B) Chitin (C) Glycogen (D) Hyaluronate (E) Starch
【已刪除】67. Glycoaminoglycans consist of a linear chain of repeating disaccharides. Which of the following polysaccharide is not glycoaminoglycans? (A) Chondroitin sulfate (B) Keratan sulfate (C) Dermatan sulfate (D) Heparin (E) Sialic acid
【已刪除】68. Gluconeogenesis synthesizes glucose, while glycolysis catabolizes glucose. It is evident that gluconeogenesis and glycolysis must be controlled in reciprocal fashion. Which of the following enzymes for glycolysis are not used in the gluconeogenic pathway? ① Hexokinase ② Phosphofructokinase ③ Phosphoglycerate kinase ④ Triosephosphate isomerase ⑤ Pyruvate kinase (A) ①②③ (B) ①②④ (C) ①②⑤ (D) ②③⑤ (E) ③④⑤ 
【已刪除】69. The potent allosteric activator for phosphofructokinase-1 in glycolysis is _______. (A) fructose 1,6-bisphosphate (B) citrate (C) ATP (D) fructose 2,6-bisphosphate (E) acetyl-CoA
【已刪除】70. Which of the following compounds can prevent electron transfer from the Fe-S center to ubiquinone in oxidative phosphorylation process? (A) Rotenone (B) Cyanide (C) 2,4-Dintrophenol (D) Oligomycin (E) Valinomycin
【已刪除】71. Which of the following fatty acids cannot be synthesized by human? (A) Linoleate [18:2(Δ9,12)] (B) Stearate (18:0) (C) Oleate [18:1(Δ9 )] (D) Palmitoleate [16:1(Δ9 )] (E) Arachidonate [20:4(Δ5,8,11,14)]
【已刪除】72. Ketone bodies are overproduced in diabetes and during starvation. Which of the following metabolites is not an intermediate from two molecules of acetyl-CoA to acetone? (A) Acetoacetyl-CoA (B) β-hydroxy-β-methylglutaryl-CoA (C) Acetoacetate (D) β-hydroxybutyrate (E) CoA-SH
【已刪除】73. Which is not involved in fatty acid oxidation? (A) Starts from carboxylate end (B) Acyl-CoA dehydrogenase (C) Acyl-CoA hydratase (D) β-hydroxyacyl-CoA dehydrogenase (E) Acyl-CoA acetyltransferase
【已刪除】74. Which is the potent inhibitor of carnitine acyltransferase I? (A) Carnitine (B) Acetyl-CoA (C) Malonyl-CoA (D) Succinyl-CoA (E) Fumarate
【已刪除】75. Flippases are enzymes that flip _______. (A) phospholipids across to the other side of a membrane (B) cholesterol from one organelle to another (C) protons across to the other side of a membrane (D) D-glucose to L-glucose (E) L-form amino acids to D-form amino acids
【已刪除】76. Degradation of amino acids can produce the precursors that are used to synthesize glucose or convert to ketone bodies. Which of the following amino acids can convert into precursors for the synthesis of glucose? ① Leucine ② Lysine ③ Cysteine ④ Asparagine ⑤ Methionine (A) ①②③ (B) ①②④ (C) ②③④ (D) ②④⑤ (E) ③④⑤
【已刪除】77. A deficiency of branched chain α-keto acid dehydrogenease complex causes the defect in metabolism of amino acids. The accumulation of α-keto acid in urine leads to maple syrup urine disease. Which of the following amino acids are metabolized by α-keto acid dehydrogenease complex? ① Methionine ② Leucine ③ Isoleucine ④ Valine ⑤ Alanine (A) ①②⑤ (B) ①③⑤ (C) ②③④ (D) ②④⑤ (E) ③④⑤
【已刪除】78. Defect in metabolism of phenylalanine causes phenylketounia and alkaptonuria. Which of the following statements are correct? ① A person with phenylketonuria will convert phenylalanine to phenylpyruvate. ② A person suffering from phenylketonuria on consumption food containing high phenylalanine may lead to the accumulation of tyrosine. ③ A person with phenylketonuria is advised not to consume aspartame. ④ Alkaptonuria is due to defect in phenylalanine hydroxylase. ⑤ A person suffering from phenylketonuria on consumption food containing high phenylalanine may lead to the accumulation of acetoacetyl-CoA. (A) ①② (B) ①③ (C) ①④ (D) ②③ (E) ②⑤
【已刪除】79. The de novo purine nucleotide synthesis relies upon the conversion of _______ to _______as a primary source of one carbon unit. (A) alanine; pyruvate (B) phenylalanine; tyrosine (C) serine; glycine (D) glutamate; α-ketoglutarate (E) aspartate; oxaloacetate
【已刪除】80. Which of the following statements for thermal denatuation of DNA are false? ① The absorption of ultraviolet at 260 nm increases. ② The DNA helical structure unwinds. ③ The covalent N-glycosidic bond between the base and the deoxyribose breaks. ④ The melting temperature of DNA with 60% A+T content is lower than that with 20% G+C content. ⑤ The double-helical DNA becomes single-stranded DNA at melting temperature. (A) ①③⑤ (B) ①③④ (C) ①④⑤ (D) ②③④ (E) ③④⑤
【已刪除】81. Which of the following enzymes does not require a template? (A) RNA polymerase II (B) DNA polymerase (C) Polyadenylate polymerase (D) Telomerase (E) Reverse transcriptase 
【已刪除】82. Which is not a true statement about reverse transcriptase? (A) The direction of polynucleotide synthesis is 5'  3'. (B) It has 3'  5' exonuclease activity. (C) It synthesizes DNA complementary to an RNA template. (D) It synthesizes DNA complementary to a DNA template. (E) It degrades the RNA strand of the RNA-DNA hybrid.
【已刪除】83. Many proteins are involved in DNA replication of E. coli. Which of the following pairs of protein and function are correct? ① DNA gyrase, unwinding DNA ② DnaA, helicase ③ DNA polymerase I, excises RNA primer and fills in with DNA ④ DNA polymerase II holoenzyme, 5'  3' exonuclease ⑤ DNA polymerase III holoenzyme, elongation (DNA synthesis) (A) ②③⑤ (B) ②③④ (C) ①③④ (D) ①③⑤ (E) ①②⑤
【已刪除】84. Which DNA repair system is likely to be used in repairing DNA with an uracil residue? (A) Base-excision repair (B) Mismatch repair (C) Direct repair (D) Nucleotide-excision repair (E) Recombinational DNA repair
【已刪除】85. Aptamers are _______. (A) double-stranded RNA products of nuclease action on hairpin RNAs (B) repeat sequence elements at the ends of transposons (C) small RNA molecules selected for tight binding to specific molecular targets (D) the RNA primers required for retroviral replication (E) the short tandem repeat units found in telomeres
【已刪除】86. Which of the following modification elucidates the inhibitory effect of diphtheria toxin on the function of eukaryotic translation factor eEF2? (A) Phosphorylation (B) Dephosphorylation (C) ADP-ribosylation (D) Prenylation (E) S-Nitrosylation
【已刪除】87. Elongation factor Tu (EF-Tu): (A) binds GTP promoting translocation of ribosomes along mRNA (B) displaces GDP from the elongation complex (C) binds aminoacyl-tRNA in the presence of GTP (D) binds initiator tRNA and GTP (E) binds to 30S subunit and drives mRNA binding
【已刪除】88. Selenocysteine (Sec) and pyrrolysine (Pyl) are recognized as 21st and 22nd amino acids, respectively. tRNASec and tRNAPyl have anticodon pairing with _______ and _______, respectively. (A) UAA, CUG (B) UGA, UAG (C) UAA, UAG (D) UAG, UGA (E) UAG, UAA
【已刪除】89. Which step about regulation of gene expression by insulin is not correct? (A) Insulin receptor binds insulin and undergoes autophosphorylation. (B) Insulin receptor binds IRS-1 on its Tyr residues. SH3 domain of Grb2 binds to phosphorylated Tyr of IRS-1. (C) Sos binds to Grb2, then to Ras, causing GDP release and GTP binding to Ras. (D) Activated Ras binds and activates Raf-1. (E) Raf-1 phosphorylates MEK. MEK phosphorylates MAPK, activating it.
【已刪除】90. Which description about β-adrenergic pathway (a G-protein coupling receptor; GPCR) is not correct? (A) The receptor is a 7-transmembrane protein. (B) Epinephrine binds to a GPCR. (C) The occupied receptor could cause the replacement of the GDP bound to GS (stimulatory G protein) by GTP, activating GS. (D) GSβ moves to adenylyl cyclase and activates it to synthesize cAMP. (E) cAMP activates PKA to trigger cellular response.

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