Reading comp PrepTest 156 · Section 3 · Question 24
Passage
Passage walkthrough
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)
- Cause-and-effect relationships, according to the author:
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)
- Author's view:
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)
- Comparison, according to the author:
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.
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
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
Why the credited answer is right
Credited answer: D
The notes below walk through why it fits the stem and how to eliminate the rest.
Strategy Overview
Answer Anticipation
Answer choices
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Awithout funding from government Remaining source text redacted.
Why choice A is not credited
Does this answer choice say the author meant "not just as a replacement for polyacrylates."
Nope, so we can cross (A) off. Besides, in our review of the last paragraph, we didn't read anything about funding from government agencies. We have no reason to believe the Koskan thought polyaspartate could be market-competitive "without funding from government agencies."
-
Bwithout reference to its Remaining source text redacted.
Why choice B is not credited
Does this answer choice say the author meant "not just as a replacement for polyacrylates."
No, so we can eliminate (B). Further, it doesn't make sense that Koskan thought polyaspartate could be market-competitive "without reference to its chemical properties." The chemical properties are what might allow polyaspartate to "enliven the environmental chemistry sector" (P4, S7).
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Conce its newest industrial Remaining source text redacted.
Why choice C is not credited
Does this answer choice say the author meant "not just as a replacement for polyacrylates."
No, so we can cross off (C). Plus, it doesn't make sense that Koskan thought polyaspartate could be market-competitive "once its newest industrial uses are more widely publicized." Koskan didn't find new applications for polyaspartate until after Koskan "decided to persevere" when the chemical industry lost interest in polyaspartate (P4, S4).
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Dnot merely as a Remaining source text redacted.
Why choice D matches the stem
Does this answer choice say the author meant "not just as a replacement for polyacrylates."
Yes! Let's select (D) and move on.
-
Ebecause of its unsurpassed Remaining source text redacted.
Why choice E is not credited
Does this answer choice say the author meant "not just as a replacement for polyacrylates."
Nope, but this answer choice is pretty tempting. However, this messes up the chronology of events. Koskan thought polyaspartate could be market-competitive on its own merits when the chemical industry lost interest in polyaspartate (P4, S4). The author claims that "since" Koskan decided to persevere, Koskan discovered that polyaspartate shows "unparalleled success at eliminating scale" (P4, S5). So, at the time Koskan thought polyaspartate could be market-competitive on its own merits, it's unclear whether Koskan knew that polyaspartate had an "unsurpassed ability to reduce scale." If Koskan didn't know of polyaspartate's ability to reduce scale to this degree, he definitely didn't think that polyaspartate could be market-competitive for this reason.
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