【正文】 ly described antibiotics. After further research they eventually reduced their substance to a fine, yellow powder, which they first named fungiciden, then renamed nystatin (to honor the New York State laboratory) when they learned the previous name was already in use. Of their major discovery, Brown said lightly that it simply illustrated how unpredictable consequences can e from rather modest beginnings.45. What is the main topic of the passage?(A) The lives of Hazen and Brown. (B) The development of a safe fungicide. (C) The New York State Department of Health.(D) The development of penicillin. 46. What can be inferred from the passage about penicillin? (A) It effectively treats fungus infections. (B) It was developed before nystatin.(C) It was developed the Second World War. (D) One of the byproducts is nystatin. 47. Why does the author mention Columbia University in lines 10 and 11? (A) Hazen and Brown developed nystatin there.(B) Brown was educated there. (C) Hazen did research there. (D) It awarded a prize to Hazen and Brown. 48. The word both in line 11 refers to (A) Hazen and Brown (B) Penicillin and streptomycin (C) the Department of Health laboratories at Albany and New York (D) double effect 49. What substance did Brown and Hazen analyze? (A) Dirt (B) Streptomycin(C) Penicillin (D) Bacteria 50. Who was W. B. Bourse? (A) A microbiologist (B) A teacher of Hazen39。s(C) A collector of fungi(D) A farmer Example three: (沒講)Fungi, of which there are over 100,000 species, including yeasts and other singlecelled organisms as well as the mon molds and mushrooms, were formerly classified as members of the plant kingdom. However, in reality they are Line very different from plants and today they are placed in a separate group altogether. (5) The principal reason for this is that none of them possesses chlorophyll, and since they cannot synthesize their own carbohydrates, they obtain their supplies either from the breakdown of dead organic matter or from other living organisms. Furthermore the walls of fungal cells are not made of cellulose, as those of plants are, but of another plex sugarlike polymer called chitin, the material from which (10) the hard outer skeletons of shrimps, spiders, and insects are made. The difference between the chemical position of the cell walls of fungi and those of plants is of enormous importance because it enables the tips of the growing hyphae, the threadlike cells of the fungus, to secrete enzymes that break down the walls of plant cells without having any effect on those of the fungus itself. It is these cellulose (15) destroying enzymes that enable fungi to attack anything made from wood, wood pulp, cotton, flax, or other plant material. The destructive power of fungi is impressive. They are a major cause of structuraldamage to building timbers, a cause of disease in animals and humans, and one of the greatest causes of agricultural losses. Entire crops can be wiped out by fungal (20) attacks both before and after harvesting. Some fungi can grow at +50176。C, while others can grow at 5176。C, so even food in cold storage may not be pletely safe from them. On the other hand, fungi bring about the deposition of dead organic matter, thus enriching the soil and returning carbon dioxide to the atmosphere. They also enter into a number of mutually beneficial relationships with plants and other (25) organisms. In addition, fungi are the source of many of the most potent antibiotics used in clinical medicine, including penicillin. 11. What does paragraph 1 mainly discuss?(A) Differences between simply and plex fungi(B) Functions of chlorophyll in plants(C) Functions of sugar in the walls of fungal cells(D) Differences between fungi and plants12. Which of the following is mentioned as a major change in how scientists approach the study of fungi?(A) Fungi are no longer classified as plants.(B) Some singlecell organisms are no longer classified as fungi.(C) New methods of species identification have been introduced.(D) Theories about the chemical position of fungi have been revised.13. The word principal in line 5 is closest in meaning to (A) true(B) main(C) logical(D) obvious14. According to the passage, how do fungi obtain carbohydrates?(A) They absorb carbohydrates from their own cell walls.(B) They synthesize chlorophyll to produce carbohydrates.(C) They produce carbohydrates by breaking down chitin.(D) They acquire carbohydrates from other organic matter, both living and dead.15. The passage mentions shrimps, spiders, and insects in line 10 because their skeletons(A) can be destroyed by fungi (B) have unusual chemical positions(C) contain a material found in the walls of fungal cells(D) secrete the same enzymes as the walls of fungal cells do16. Which of the following terms is defined in the passage?(A) chlorophyll (line5)(B) polymer (line9)(C) hyphae (line12)(D) enzymes (line13)17. The word those in line 14 refers to(A) tips(B) hyphae(C) enzymes (D) walls18. Fungi have all of the following characteristics EXCEPT:(A) They grow hyphae.(B) They secrete enzymes.(C) They synthesize cellulose.(D) They destroy crops.19. The word Entire in line 19 is closest in meaning to (A) certain(B) whole(C) mature(D) diseased20. The passage describes the negative effects of fungi on all of the following EXCEPT(A) buildings(B) animals(C) food(D) soil21. The phrase bring about in line 22 is closest in meaning to (A) cause(B) join(C) take(D) include22. The passage mentions penicillin in line 26 as an example of (A) a medicine derived from plants(B) a beneficial use of fungi(C) a product of the relationship between plants and fungi (D) a type of fungi that grows at extreme temperatures.Passage 1:When Jules Verne wrote Journey to the Center of the Earth in 1864, there were many conflict