One of the most noxious wind-borne allergens is ragweed (Ambrosia), as

Question

One of the most noxious wind-borne allergens is ragweed (Ambrosia), as evidenced by an estimated 30 million sufferers in the U.S. alone and a societal cost of over $3 billion. Each plant is able to produce more than a billion grains of pollen over the course of a season, and the plant is the prime cause of most cases of hay fever in North America. Although the plant produces more pollen in wet years, humidity rates above seventy percent tend to depress the spread of pollen by causing the grains to clump.

Ragweed spreads rapidly by colonizing recently disturbed soil, such as that engendered by roads, subdivisions, and cultivation and has adapted to a multitude of climatic conditions, including desert and high mountain areas. Complete elimination is virtually impossible. Physical removal is undone by even one seed or one bit of root left behind. Ragweed regenerates in about two weeks from only a half-inch of stem, usually with additional branching and flowering, so mowing can actually be counterproductive. Ragweed is susceptible to only the most aggressive herbicides, and because ragweed tends to cover large areas, control would mean widespread use of highly toxic chemicals. Control by natural predators? No known mammal browses on ragweed. Some species of Lepidoptera (butterflies, skippers, and moths) larvae feed on ragweed, but this arena of control is not well funded, and consequently not well-researched. Given the health issues and costs occasioned by ragweed, government funding for natural control research is warranted.    1  
 1. Which of the following can be inferred about the spread of ragweed pollen?

A. Allergies caused by the spread of ragweed pollen cost the U.S. more to treat than any other type of allergy.
B. Some ragweed plants produce fewer grains of pollen when exposed to certain highly toxic herbicides.
C. Ragweed plants adapted to desert and mountain climes tend to spread fewer grains of pollen than do plants in other locations.
D. The clumping of pollen grains caused by high humidity levels affects the ability of the wind to carry the grains.
E. The spread of ragweed pollen is the cause of all cases of hay fever in the United States. 
 
 2  
 2. The author most probably mentions some species of Lepidoptera in order to

A. detail a species that may be more effective at controlling ragweed than are the most aggressive herbicides
B. suggest a potential research avenue to the problem of controlling ragweed that is at present poorly explored
C. discuss a type of mammal that feeds on ragweed plants and may be successful at controlling the spread of ragweed
D. plead with the government to spend more money and put more research efforts into fnding a natural control for ragweed
E. argue that complete elimination of the ragweed plant will only be possible if the government funds research into natural controls of ragweed

Sajjad1994 · Answer

OE

1. Which of the following can be inferred about the spread of ragweed pollen?

The first paragraph states that ragweed is one of the most noxious wind-borne allergens. Later, the paragraph states that humidity rates above seventy percent tend to depress the spread of pollen by causing the grains to clump. If the pollen is borne by the wind and its spread is depressed by clumping, the clumping must have some negative affect on the wind’s ability to carry the pollen. The passage doesn’t mention the cost of treating other allergies, so  choice (A)  is wrong. Nothing supports  choice (B) . The passage doesn’t compare the rates of production of plants in different climates, so  choice (C)  cannot be inferred.  Choice (E)  goes too far; the passage states that ragweed pollen is the cause of most cases not all as the choice states. 
 
  Answer: D

Sajjad1994 · Answer

OE

2. The author most probably mentions some species of Lepidoptera in order to

The answer to this question lies in the line, Some species of Lepidoptera (butterflies, skippers, and moths) larvae feed on ragweed, but this arena of control is not well funded, and consequently not wellresearched. The author mentions the species to indicate that there may be a potential answer to the problem of controlling ragweed, but this answer has not been fully explored. This most closely matches  choice (B).

Choice (A)  is wrong because the author doesn’t make a comparison between the methods of control.

Choice (C)  is wrong because the species discussed are not mammals.

The author does suggest the government explore natural remedies, but  choice (D)  doesn’t properly answer the question.

The mention of some species of Lepidoptera is not used to plead with the government.  Choice (E)  is incorrect because earlier in the passage the author indicates that complete elimination of the ragweed is unlikely. 
 
  Answer: B

One of the most noxious wind-borne allergens is ragweed (Ambrosia), as

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