Reading comp PrepTest 156 · Section 3 · Question 22

Passage

  Organic chemist Larry Koskan's inspiration arrived in the mid-1980s, when he read a report by marine biologists describing how oyster Remaining source text redacted.
Passage walkthrough
Passage Summary

Topic: Science


Paragraph 1

  • Paragraph note
    • Background on Koskan’s inspiration (discovery that oysters produce protein-based agents)

Paragraph 2

  • Paragraph note
    • Comparison of polyacrylates (used to decrease scale on water-treatment equipment) and oyster's polyaspartate (can also decrease scale, but is biodegradable)
  • Views, minor Meta-Structures, and the author’s attitude
    • Cause-and-effect relationships, according to the author:
      • Polyacrylate causes a decrease in damaging mineral-scale deposits on surfaces of water-treatment equipment (second sentence)
      • Polyaspartate causes a decrease in the formation of calcium carbonate, which causes a decrease in damaging mineral-scale deposits on surfaces of water-treatment equipment (third sentence)
    • Comparisons, according to the author:
      • Polyacrylate and polyaspartate have a similar chemical structure (fourth sentence)
      • Unlike polyacrylate, polyaspartate is made up of peptides, so it is biodegradable (last sentence)

Paragraph 3

  • Paragraph note
    • Problem with polyacrylates (prevalent in detergents and diapers but last forever in landfills)
  • Views, minor Meta-Structures, and the author’s attitude
    • Author's view:
      • Polyacrylates are inexpensive and versatile, so they are used extensively in laundry detergents and baby diapers, even though they last virtually forever in landfills (first through last sentences)
    • Author's attitude: "inexpensive and versatile" (first sentence); "ideal" (fourth sentence); "trouble" (last sentence); "last virtually forever" (last sentence); "vast quantities" (last sentence)

Paragraph 4

  • Paragraph note
    • Author on the industry's waning interest in polyaspartate (too expensive) and the success of Koskan's company (successful at eliminating scale in offshore oil equipment and keeping fertilizer in soil)
  • Views, minor Meta-Structures, and the author’s attitude
    • Comparison, according to the author:
      • While the consumer products and chemical industry's early enthusiasm for polyaspartate eventually waned as it proved too expensive, Koskan's company believed that polyaspartate could work in specialized applications (second through fifth sentences)
    • Author's view:
      • Polyaspartate has shown unmatched success at eliminating scale in offshore oil equipment and reducing groundwater pollution, and Koskan's company's continued success would revitalize an environmental chemical industry with a reputation for ineffectiveness and high cost (sixth and last sentences)
    • Author's attitude: "growing rapidly" (first sentence); "Unfortunately" (third sentence); "unparalleled success" (sixth sentence); "may yet help enliven an environmental chemistry sector saddled with a reputation for ineffectiveness and high cost" (last sentence)

Main Point: Although using polyaspartate as a more environmentally friendly alternative to polyacrylate has proven too expensive for many companies, Koskan's use of polyaspartate in specialized applications has shown tremendous success.

Meta-Structure?

Problem/Solution: This passage best fits the Problem/Solution Meta-Structure*. In such a passage, the author will describe an issue and one or more potential solutions. In this particular passage, the author presents the problem with the extensive use of polyacrylates. While they are cheap and versatile (and less environmentally damaging than some products), they pretty much last forever in landfills. The author presents polyaspartate as a possible solution — this chemical functions similarly to polyacrylates, but they're biodegradable and thus more environmentally friendly.

In a Problem/Solution passage, the main point is generally the author’s opinion on the solution. The author doesn't summarize their opinion in one or two sentences, so we had to compose our own summary: "Although using polyaspartate as a more environmentally friendly alternative to polyacrylate has proven too expensive for many companies, Koskan's use of polyaspartate in specialized applications has shown tremendous success."

*That said, a few other Meta-Structures could work for this passage. You could certainly call this an Innovative [Subject] or Importance of [Subject] passage, framing Koskan as the innovative/important figure. If you classified this passage as either of these Meta-Structures, you'd probably come to a similar understanding of the passage's main point and organization.

Comparison: The author compares and contrasts polyacrylate and polyaspartate several times in this passage, making the comparison the most prominent minor Meta-Structure. Expect a question or two about these. To avoid some fact-finding missions and save some time, you can commit a few similarities and differences to memory if this isn't too onerous:

  • Similarities: Similar chemical structure, both decrease scale
  • Differences: Polyaspartate is made up of peptides and not hydrocarbon, polyaspartate is biodegradable, polyacrylate is cheap

Last Thoughts?

The words "polyacrylate" and "polyaspartate" are long, very similar, and there's a good chance you're unfamiliar with both. We're going to have a bad time if we mix them up. So, let's devise a strategy to make sure we know which is which. Personally, we're just going to scan the end of the word to see if it ends with "-late" or "-tate." The one that ends with "-late" has been used to control scale and put in products like laundry detergent and baby diapers. It's also the one that Koskan wants to say "late(r)" to, replacing it with the more modern "-tate." The "-tate" one is also biodegradable ... like a po-tate-o? Whatever the mnemonic device you come up with, the questions will be much easier if we can remember which one is "polyacrylate" and which is "polyaspartate."

Question prompt

Which one of the Remaining source text redacted.
Why the credited answer is right

Credited answer: C

The notes below walk through why it fits the stem and how to eliminate the rest.

Strategy Overview

Reiterate the main point as we summarized it after reading through the passage, then find the answer that best matches it

Answer Anticipation

As discussed in the Meta-Structure section above, this passage utilizes a Problem/Solution Meta-Structure. In such a Meta-Structure, the main point is generally the author’s opinion on the solution. The author doesn't summarize their opinion in one or two sentences, so we had to compose our own summary: "Although using polyaspartate as a more environmentally friendly alternative to polyacrylate has proven too expensive for many companies, Koskan's use of polyaspartate in specialized applications has shown tremendous success." Let's look for the answer choice that contains the same ideas as our anticipation.

Answer choices

  1. A
    Polyaspartate was once thought Remaining source text redacted.
    Why choice A is not credited

    Does this contain the same ideas as our anticipated main point?

    No, this answer choice is too negative, as our anticipated main point focuses on polyaspartate's promise at least as much as its shortcomings. Further, this answer choice mischaracterizes the problem with polyaspartate. Our anticipation concedes that polyaspartate has proven too expensive for many companies, not that "technical shortcomings" hold back the use of polyaspartate. For these reasons, we can cross off (A).

  2. B
    The success of Koskan's Remaining source text redacted.
    Why choice B is not credited

    Does this contain the same ideas as our anticipated main point?

    Not quite, but this is really tempting! This answer choice is very similar to the last sentence, making it catnip to many test-takers — especially those who erroneously assume the last sentence is always the author's conclusion.

    However, there are a few issues with this answer choice. First, it's not even an accurate representation of the last sentence. The last sentence says, "If Koskan’s company can show continued success," it may "enliven" the environmental chemistry sector (P4, S7). That "if" part is crucial. The author believes that Koskan's company will have to continue to be successful to guarantee improvement in the environmental chemistry sector. This answer choice says that Koskan's company's current success will improve the environmental chemistry sector. Moreover, the author never claims that Koskan's success will improve the reputation of the environmental chemistry industry. The author acknowledges that this industry has a bad reputation and that Koskan's success will reinvigorate the industry, but that doesn't necessarily imply that its reputation will improve as well.

    Second, this answer choice only focuses on polyaspartate's positives. However, the author concedes that there is at least one major issue with polyaspartate's use — its expense (P4, S3). The author dedicates about half of the last paragraph to industries' reluctance to use polyaspartates, so that issue should show up in the main point.

    For these reasons, we need to eliminate (B).

  3. C
    Polyaspartate, which Koskan researched Remaining source text redacted.
    Why choice C matches the stem

    Does this contain the same ideas as our anticipated main point?

    This isn't a perfect match for our anticipation, but it's the closest match so far. Importantly, it captures both the author's positive feelings toward polyaspartate ("shows promise for commercial applications") and the author's opinion on its shortcomings ("also faces barriers"). Further, this answer choice doesn't mischaracterize any facts in this passage.

    This answer choice probably isn't close enough to our anticipation to select without reading the remaining answer choices. But we can mark it as a strong contender. If we can find reasons to eliminate the remaining options, we can select it confidently.

  4. D
    Koskan's work with polyaspartate Remaining source text redacted.
    Why choice D is not credited

    Does this contain the same ideas as our anticipated main point?

    No. This answer choice makes it seem like this is a Generalization/Example passage — that Koskan's inspiration from oysters is just one of many examples of times that environmentally friendly products were "found by studying plants and animals." However, the fact that Koskan took inspiration from oysters is the only example of this phenomenon that we learn about. Moreover, the oyster epiphany is a relatively minor part of the passage. The passage focuses far more on polyasparate's benefits and drawbacks, a topic that this answer choice omits. For these reasons, we need to eliminate (D).

  5. E
    Although polyaspartate is superior Remaining source text redacted.
    Why choice E is not credited

    Does this contain the same ideas as our anticipated main point?

    Negative. Like (A), this answer choice is too negative. Our anticipated main point focuses on polyaspartate's promise at least as much as its limitations in the marketplace. It's also inaccurate to say that polyaspartate will "probably fail in the marketplace," as Koskan's applications in specialized fields have already shown great success. Therefore, we can cross off (E).

Question analytics

Based on historical answer selection rates for this question.

Answer choice distribution

  1. A 9%
  2. B 19%
  3. C Credited 68%
  4. D 3%
  5. E 1%

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