yellowsaffire Posted February 3, 2006 Share Posted February 3, 2006 Mycorrhizal fungi infect more plants than do any other fungi and are necessary for many plants to thrive, but they have escaped widespread investigation until recently for two reasons. First, the symbiotic association is so well-balanced that the roots of host plants show no damage even when densely infected. Second, the fungi cannot as yet be cultivated in the absence of a living root. Despite these difficulties, there has been important new work that suggests that this symbiotic association can be harnessed to achieve more economical use of costly superphosphate fertilizer and to permit better exploitation of cheaper, less soluble rock phosphate. Mycorrhizal benefits are not limited to improved phosphate uptake in host plants. In legumes, mycorrhizal inoculation has increased nitrogen fixation beyond levels achieved by adding phosphate fertilizer alone. Certain symbiotic associations also increase the host plant’s resistance to harmful root fungi. Whether this resistance results from exclusion of harmful fungi through competition for sites, from metabolic change involving antibiotic production, or from increased vigor is undetermined. 17. Which of the following most accurately describes the passage? (A) A description of a replicable experiment (B) A summary report of new findings © A recommendation for abandoning a difficult area of research (D) A refutation of an earlier hypothesis (E) A confirmation of earlier research 18. The level of information in the passage above is suited to the needs of all of the following people EXCEPT: (A) a researcher whose job is to identify potentially profitable areas for research and product development (B) a state official whose position requires her to alert farmers about possible innovations in farming © an official of a research foundation who identifies research projects for potential funding (D) a biologist attempting to keep up with scientific developments in an area outside of his immediate area of specialization (E) a botanist conducting experiments to determine the relationship between degree of mycorrhizal infection and expected uptake of phosphate 19. It can be inferred from the passage that which of the following has been a factor influencing the extent to which research on mycorrhizal fungi has progressed? (A) Lack of funding for such research (B) Lack of immediate application of such research © Lack of a method for identifying mycorrhizal fungi (D) Difficulties surrounding laboratory production of specimens for study（D） (E) Difficulties ensuing from the high cost and scarcity of superphosphate fertilizers 20. The passage suggests which of the following about the increased resistance to harmful root fungi that some plants infected with mycorrhizal fungi seem to exhibit? (A) There are at least three hypotheses that might account for the increase. (B) An explanation lies in the fact that mycorrhizal fungi increase more rapidly in number than harmful root fungi do. © The plants that show increased resistance also exhibit improved nitrogen fixation. (D) Such increases may be independent of mycorrhizal infection.（A） (E) It is unlikely that a satisfactory explanation can be found to account for the increase. Can i share ur answers? i doubt my answer key Quote Link to comment Share on other sites More sharing options...
seagull Posted February 3, 2006 Share Posted February 3, 2006 17. Which of the following most accurately describes the passage? (A) A description of a replicable experiment (B) A summary report of new findings © A recommendation for abandoning a difficult area of research (D) A refutation of an earlier hypothesis (E) A confirmation of earlier research 18. The level of information in the passage above is suited to the needs of all of the following people EXCEPT: (A) a researcher whose job is to identify potentially profitable areas for research and product development (B) a state official whose position requires her to alert farmers about possible innovations in farming © an official of a research foundation who identifies research projects for potential funding (D) a biologist attempting to keep up with scientific developments in an area outside of his immediate area of specialization (E) a botanist conducting experiments to determine the relationship between degree of mycorrhizal infection and expected uptake of phosphate 19. It can be inferred from the passage that which of the following has been a factor influencing the extent to which research on mycorrhizal fungi has progressed? (A) Lack of funding for such research (B) Lack of immediate application of such research © Lack of a method for identifying mycorrhizal fungi (D) Difficulties surrounding laboratory production of specimens for study (E) Difficulties ensuing from the high cost and scarcity of superphosphate fertilizers 20. The passage suggests which of the following about the increased resistance to harmful root fungi that some plants infected with mycorrhizal fungi seem to exhibit? (A) There are at least three hypotheses that might account for the increase. (B) An explanation lies in the fact that mycorrhizal fungi increase more rapidly in number than harmful root fungi do. © The plants that show increased resistance also exhibit improved nitrogen fixation. (D) Such increases may be independent of mycorrhizal infection.（A） (E) It is unlikely that a satisfactory explanation can be found to account for the increase. Quote Link to comment Share on other sites More sharing options...
yellowsaffire Posted February 4, 2006 Author Share Posted February 4, 2006 Sea ..... thanx for the reply. cud i also have ur explanations? Quote Link to comment Share on other sites More sharing options...
seagull Posted February 4, 2006 Share Posted February 4, 2006 17. Which of the following most accurately describes the passage? (A) A description of a replicable experiment (B) A summary report of new findings © A recommendation for abandoning a difficult area of research (D) A refutation of an earlier hypothesis (E) A confirmation of earlier research line 6 - Despite these difficulties, there has been important new work that suggests that this symbiotic association can be ....... 18. The level of information in the passage above is suited to the needs of all of the following people EXCEPT: (A) a researcher whose job is to identify potentially profitable areas for research and product development (B) a state official whose position requires her to alert farmers about possible innovations in farming © an official of a research foundation who identifies research projects for potential funding (D) a biologist attempting to keep up with scientific developments in an area outside of his immediate area of specialization (E) a botanist conducting experiments to determine the relationship between degree of mycorrhizal infection and expected uptake of phosphate the level of information metioned in the passage suits to all the people in A,B,C and E. but in D, a biologist is working outside his immediate area of specialization , whereas the passage contains information relevant to biology. 19. It can be inferred from the passage that which of the following has been a factor influencing the extent to which research on mycorrhizal fungi has progressed? (A) Lack of funding for such research (B) Lack of immediate application of such research © Lack of a method for identifying mycorrhizal fungi (D) Difficulties surrounding laboratory production of specimens for study (E) Difficulties ensuing from the high cost and scarcity of superphosphate fertilizers got it thru elimination. there is no information in the passage regarding the information in A,B,D, and E. only C suits best. furthermore in line 2 but they have escaped widespread investigation until recently for two reasons. First, the symbiotic association is so well-balanced that the roots of host plants show no damage even when densely infected. Second, the fungi cannot as yet be cultivated in the absence of a living root. Despite these difficulties,...... properly justifies C 20. The passage suggests which of the following about the increased resistance to harmful root fungi that some plants infected with mycorrhizal fungi seem to exhibit? (A) There are at least three hypotheses that might account for the increase. (B) An explanation lies in the fact that mycorrhizal fungi increase more rapidly in number than harmful root fungi do. © The plants that show increased resistance also exhibit improved nitrogen fixation. (D) Such increases may be independent of mycorrhizal infection.（A） (E) It is unlikely that a satisfactory explanation can be found to account for the increase. it was mentioned in the last two lines. look at the three hypothesis colored below... Certain symbiotic associations also increase the host plant’s resistance to harmful root fungi. Whether this resistance results from exclusion of harmful fungi through competition for sites, from metabolic change involving antibiotic production, or from increased vigor is undetermined. hope it looks clear :) Quote Link to comment Share on other sites More sharing options...
yellowsaffire Posted February 4, 2006 Author Share Posted February 4, 2006 i way agree...but the key has different ans for the qs 18th n 19th. anyways u r brilliant. much thanx for the effort by the way how much time shud it take to solve a set ( 2 passages 11 questions) Quote Link to comment Share on other sites More sharing options...
Frederick Almad Posted September 21, 2013 Share Posted September 21, 2013 17. Which of the following most accurately describes the passage? (A) A description of a replicable experiment (B) A summary report of new findings © A recommendation for abandoning a difficult area of research (D) A refutation of an earlier hypothesis (E) A confirmation of earlier research 18. The level of information in the passage above is suited to the needs of all of the following people EXCEPT: (A) a researcher whose job is to identify potentially profitable areas for research and product development (B) a state official whose position requires her to alert farmers about possible innovations in farming © an official of a research foundation who identifies research projects for potential funding (D) a biologist attempting to keep up with scientific developments in an area outside of his immediate area of specialization (E) a botanist conducting experiments to determine the relationship between degree of mycorrhizal infection and expected uptake of phosphate 19. It can be inferred from the passage that which of the following has been a factor influencing the extent to which research on mycorrhizal fungi has progressed? (A) Lack of funding for such research (B) Lack of immediate application of such research © Lack of a method for identifying mycorrhizal fungi (D) Difficulties surrounding laboratory production of specimens for study (E) Difficulties ensuing from the high cost and scarcity of superphosphate fertilizers 20. The passage suggests which of the following about the increased resistance to harmful root fungi that some plants infected with mycorrhizal fungi seem to exhibit? (A) There are at least three hypotheses that might account for the increase. (B) An explanation lies in the fact that mycorrhizal fungi increase more rapidly in number than harmful root fungi do. © The plants that show increased resistance also exhibit improved nitrogen fixation. (D) Such increases may be independent of mycorrhizal infection.（A） (E) It is unlikely that a satisfactory explanation can be found to account for the increase. hi there, may i get an explannatio for these answers?? cause im quite nervous about the answers... Quote Link to comment Share on other sites More sharing options...
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