こんにちは、SOLO IELTS TOEFLのルークです。
Q1. The standardized study and research of this art is a relatively new discipline in Australia. New discoveries have gradually been added to the body of knowledge over the past forty years. The most important information has come from a focus on three major questions. First, how old is Australian rock art? Second, what is its organization style and can we discern a pattern or sequence of development between styles? Third, is it possible to interpret the subject matter of ancient rock art precisely, considering all available archaeological techniques and the understanding of current Aboriginal informants?
The word “discern” in the passage is closest in meaning to
 Ranging from viruses to humans, genes from virtually all kinds of organisms can now be inserted into plants, creating what are known as transgenic plants. Now used in agriculture, there are approximately 109 million acres of transgenic crops grown worldwide, 68 percent of which are in the United States. The most common transgenic crops are soybeans, corn, cotton, and canola. More often than not, these plants will contain a gene that either makes them resistant to the herbicide glyphosate, or produces an insect-resistant protein called Bt toxin.
 Advocates of transgenic crops argue that the benefit of these crops is that they’re environmentally friendly, allowing farmers to use smaller amounts of less noxious chemicals for crop production. For example, there has been a 21 percent reduction in the use of insecticide reported on Bt cotton (a transgenic cotton that produces Bt toxin). In addition, when glyphosate is used to control weeds, other more persistent herbicides do not need to be applied.
 However, adversaries of transgenic crops suggest that there are still many unanswered questions which must be addressed before transgenic crops will be safe to grow on a larger scale. Some questions concern the effects that Bt plants have on non-target organisms, such as beneficial insects, worms, and birds that consume the genetically engineered crop. For example, monarch caterpillars feeding on milkweed plants near Bt cornfields feed on corn pollen that has fallen on the milkweed leaves. Laboratory studies indicate that caterpillars can die from eating Bt pollen. However, field tests indicate that Bt corn is not likely to harm monarchs. Furthermore, the application of pesticides (the alternative to growing Bt plants) has been demonstrated to cause widespread harm to non-target insects.
 Another question which remains unanswered is whether herbicide-resistant genes will move into the various populations of weeds. Crop plants are sometimes grown in areas where weedy relatives also live. If the crop plants crossbreed and reproduce with weedy relatives, then this herbicide-resistant gene will be perpetuated in the offspring. In this way, the resistant gene can make its way into the weed population. If this happens, a farmer can no longer use glyphosate, for example, to kill those weeds. This scenario is not likely to occur in many instances when there are no weedy relatives growing near the crop plant. However, in some cases, it may become a serious problem. For example, canola readily hybridizes with mustard weed species and could transfer its herbicide-resistant genes to those weeds. We know that evolution will occur when transgenic plants are grown on a large scale over a period of time. The development of insect populations resistant to the Bt toxin is of particular concern. This pesticide has already been applied to plants for decades without the development of insect-resistant populations. However, transgenic Bt plants express the toxin in all tissues throughout the growing season. Therefore, all insects carrying genes that make them susceptible to the toxin will die. Such an event would leave only the genetically resistant insects alive to perpetuate the population. When these resistant insects mate, they will produce a high proportion of offspring capable of surviving in the presence of the Bt toxin. Farmers are using different methods in an attempt to slow the development of insect resistance in Bt crops. For example, some farmers are planting nontransgenic border rows to provide a refuge for susceptible insects. These insects may allow Bt susceptibility to remain in the population.
 Perhaps the most serious concern about the transgenic crop plants currently in use is that they encourage farmers to move farther away from sustainable agricultural farming practices, meaning ones that allow natural resources to continually regenerate over the long run. Transgenic plants, at least superficially, simplify farming by reducing the choices made by the manager. Planting a glyphosate-resistant crop commits a farmer to use that herbicide for the season, probably to the exclusion of all other herbicides and other weed-control practices. Farmers who use Bt transgenic may not feel that they need to follow through with integrated pest-management practices that use beneficial insects and timely applications of pesticides to control insect pests. A more sustainable approach wo Coming soon! uld be to plant non-transgenic corn, monitor the fields throughout the growing season, and then apply a pesticide only if and when needed.
Questions 1 – 10
Q1. According to paragraph 2, supporters claim that producing transgenic plants enables farmers to
- Control weeds without the use of chemicals
- Take advantage of more effective pesticides
- Use fewer and less toxic chemicals
- Increase harvesting up to 21 percent
Q2. Which of the following can be inferred about monarch caterpillars from paragraph 3?
- They are considered beneficial insects.
- They are the species most resistant to herbicides.
- There is little to no existing research available concerning their behavior.
- They regularly cause harm to all kinds of crops.
Q3. What conclusion does the author make in passage 3 about the impact of Bt plants on nontarget living beings?
- Bt plants have been shown in field studies to cause great harm to micro-organisms.
- Bt plants do not cause as much harm to non-target species as the use of conventional pesticides.
- Bt toxins don’t influence non-target organisms who consume transgenic plants at all.
- Even if Bt poisons don’t influence insects that feed on the plants, they effectively affect birds and human beings.
Q4. Why does the author mention “mustard weed species” in the discussion of plants that hybridize?
- To give an example of a weed that may become resistant to glyphosate due to hybridizing with a transgenic plant
- To argue that creating transgenic plants in the laboratory is not always necessary, as some can be created through hybridizing in the fields
- To give evidence that related types of plants are unaffected by transgenic plants
- To support the claim that it is difficult to decide if a harvest plant has been planted far enough away from any weeds
Q5. Paragraph 4 makes all of the following claims about Bt resistance in insect populations EXCEPT
- Because Bt plants are toxic in all tissues, they allow no insects that are susceptible to survive and reproduce.
- The evolution of Bt-resistant insect populations will happen eventually if the use of transgenic plants becomes widespread.
- Planting no transgenic plants alongside Bt plants may help Bt-susceptible insects to remain part of the population.
- Regular use of Bt pesticides has not created resistant insect populations, so the use of Bt plants is probably safe as well.
Q6. Which of the following best expresses the essential information in the highlighted sentence? Incorrect answer choices change the meaning in important ways or leave out essential information.
Perhaps the most serious concern about the transgenic crop plants currently in use is that they encourage farmers to move farther away from sustainable agricultural farming practices, meaning ones that allow natural resources to continually regenerate over the long run.
- The transgenic crop plants currently in use are behind the transgenic plants of the future in terms of their sustainability.
- Transgenic plants grown as crops may be used in place of other, more sustainable agricultural practices, and this is perhaps their biggest disadvantage.
- Farmers who use transgenic crop plants are heading towards good growing habits which will result in a surplus amount of crops.
- The most serious concern about the transgenic crop plants currently in use is the possibility that they may not be sustainable over the long run.
Q7. According to paragraph 5, a sustainable approach to weed and pest control includes all of the following EXCEPT
- Planting non-transgenic crops
- Applying pesticides only when needed
- Keeping a close eye on the crops
- Using multiple types of herbicide throughout the growing season
Q8. The word ‘superficially’ in paragraph 5 is closest in meaning to:
- when done incorrectly
- right now
- on the surface
- with deeper analysis
Q9. Examine the four █ in the selection below and indicate at which block the following sentence could be inserted into the passage:
It is especially rare in the United States, where most transgenic plants are grown because most of the crops grown in the United States originated elsewhere.
Where would the sentence best fit?
If the crop plants crossbreed and reproduce with weedy relatives, then this herbicide-resistant gene will be perpetuated in the offspring. █ [A] In this way, the resistant gene can make its way into the weed population. █ [B] If this happens, a farmer can no longer use glyphosate, for example, to kill those weeds. █ [C] This scenario is not likely to occur in many instances because there are no weedy relatives growing near the crop plant. █ [D] However, in some cases, it may become a serious problem. For example, canola readily hybridizes with mustard weed species and could transfer its herbicide-resistant genes to those weeds..
Q.10 Directions: An introductory sentence for a brief summary of the passage is provided below.
Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points.
Transgenic plants include genes from other organisms that make them resistant to glyphosate or toxic to insects.
- Opponents of transgenic plants worry that resistance to glyphosate may spread to weeds and that resistance to Bt toxin may develop among insect pests.
- Use of transgenic plants may lead farmers to neglect more sustainable agricultural practices, and may also cause harm to non-target organisms.
- One argument against Bt plants is that some of the most harmful pests are not Bt-susceptible, making application of supplementary pesticides necessary.
- Over the long term, transgenic plants are likely to lose their glyphosate resistance through evolution and hybridization with non-resistant relatives.
- Although transgenic plants are useful in some areas, they are not particularly useful in place of pesticides.
- Proponents of transgenic plants argue that they reduce the use of harmful pesticides and allow the use of more environmentally friendly herbicides.
Q10. 1, 2, 5
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