PrepTest 155

[lcid:3718] Prep Test 155 LSAT — Reading Comp — S3 Reading comp

Passage

This passage was adapted from an article published in 2000.   Competition to make computer chips smaller and, consequently, faster Remaining source text redacted.
Passage walkthrough
Passage Summary Topic:
Science

Paragraph 1
  • Paragraph note
    • Problem (making computer chips smaller) and one possible solution (using peptides)
  • Views, minor Meta-Structures, and the author's attitude
    • Definition of "transistor": electronic devices that make up computer chips (third sentence)
    • Definition of "peptide": amino acid that makes molecular patterns (last sentence)
    • Cause-and-effect relationships:
      • Competition to make computer chips smaller has caused technologies to advance and economies to grow (first sentence)
    • Comparisons:
      • With current methods, transistors cannot be smaller than 25 nanometers, but living cells can make complex structures smaller (fourth setnece)
      • Most research into making computer chips smaller involves using DNA to assemble smaller computer chips, but Hu/Belcher attempt to use peptides/amino acids (last sentence)
    • Author's attitude: "revolution" (first sentence); "may be hope" (fourth sentence)
Paragraph 2
  • Paragraph note
    • Belcher and Hu's research (developed new peptides to bind to semiconductor materials)
  • Views, minor Meta-Structures, and the author's attitude
    • Cause-and-effect relationship:
      • A specific peptide causes calcium carbonate to turn into the structure found on abalone shells (second sentence)
    • Comparisons:
      • If a peptide can grow calcium carbonate into an abalone shell, a similar peptide could direct the growth of semiconductor materials to transistors (third sentence)
      • To find more peptides that could attach to semiconductor materials, Belcher and Hu used a process similar to accelerated evolution (last sentence)
    • List of semiconductor materials:
      • silicon, gallium arsenide, indium phosphide crystals (fifth sentence)
    • Author's attitude: "not only ... but also" (sixth sentence); "initially promising" (last sentence)
Paragraph 3
  • Paragraph note
    • Belcher and Hu's remaining goals (find more peptides that bind) and progress (promising)
  • Views, minor Meta-Structures, and the author's attitude
    • Author's view:
      • Belcher and Hu are making promising advancements in finding order to use peptides to bind to semiconductor materials (second through last sentence)
    • Comparison:
      • New peptides that can bind two different crystals function similarly to a glue (fourth sentence)
    • Author's attitude: "making progress" (second sentence); "ballooned into the hundreds" (third sentence); "will take that kind of finesse" (last sentence)


Main Point:
Hu and Belcher's promising research into using peptides to bind to computer-chip materials might allow scientists to work around the current theoretical minimum size of computer chips.

Key Lines?
Paragraph 1, Sentence 2 (P1, S2) - Problem introduced
P2, S3 - Possible solution
P3, S2-4 - Author's evaluation of the solution

Meta-Structure?
Problem/Solution: This passage best fits the Problem/Solution Meta-Structure*. The author describes a problem contemporary — well, actually, 2000s-era — technologists face: how to make computer chips smaller than the laws of physics will allow. The rest of the passage focuses on one potential solution: Belcher and Hu's use of organic compounds known as peptides to bind together computer chip materials.

In a Problem/Solution passage, the author's opinion of the proposed solution is the passage's main point. The author provides their opinion in the last paragraph. The author notes that Belcher and Hu haven't cracked the code yet, but they're making promising advancements. So, we've summarized the main point as, "Hu and Belcher's promising research into using peptides to bind to computer-chip materials might allow scientists to work around the current theoretical minimum size of computer chips."

*Some may see this as an Innovative Subject passage, since Belcher and Hu utilize such a unique approach. If this understanding of the passage makes more sense to you, that's a-OK! The Meta-Structures are here to help us think about a passage's overarching structure and ideas. We don't have to agree on which Meta-Structure a passage has to realize the benefits of the Meta-Structures.

Last Thoughts?
It's important to note, from the last paragraph, that Hu and Belcher haven't solved the problem yet — they're still working on it! The first line of the last paragraph lets us know that they haven't yet been able to assemble a circuit using peptides.

Question prompt

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

Credited answer: E

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

Question Type

Science

Answer choices

  1. A
    A group of researchers, Remaining source text redacted.
    Why choice A is not credited
    Does this reflect the key characteristics of Belcher and Hu's research into peptides?

    Nope. First, this group is studying "synthetic" oils, so they're starting with oils not found in nature. In the passage, Belcher and Hu researched organic peptides found in abalones. Second, this group completely abandons these oils to investigate a different type of chemical (acids) that are found in nature. This makes (A) disanalogous from the passage, and we can eliminate it.
  2. B
    A group of researchers Remaining source text redacted.
    Why choice B is not credited
    Does this reflect the key characteristics of Belcher and Hu's research into peptides?

    No. This answer choice presents the discovery that this oil has a use outside of its initial context. Hu and Belcher intentionally studied whether they could use peptides to build computer circuits. This answer is an accidental discovery; the stimulus presents a very intentional one. So, (B) is quite different from the peptide situation and we can eliminate it.
  3. C
    A group of researchers Remaining source text redacted.
    Why choice C is not credited
    Does this reflect the key characteristics of Belcher and Hu's research into peptides?

    Not really. The research in this answer choice starts with the synthesis of oils for a certain use, not the discovery of oils in nature. That's enough to get rid of (C).
  4. D
    A group of researchers Remaining source text redacted.
    Why choice D is not credited
    Does this reflect the key characteristics of Belcher and Hu's research into peptides?

    Not exactly. Although the researchers discovered a volatile oil in nature — much like Belcher discovered a peptide in nature — the rest of the answer choices deviate from the passage. If the rest of the answer choice said this discovery led researchers to see if the volatile oils could solve another problem, it might have presented an analogous situation. However, the researchers in this answer choice look into whether similar oils cause a problem in another context — not whether they can solve a problem in another context.
  5. E
    A group of researchers, Remaining source text redacted.
    Why choice E matches the stem
    Question Type:
    Application/Analogous Situation

    Strategy Overview:
    Review the relevant part of the passage and notes, if necessary, to anticipate key features of the research into peptides

    Answer Anticipation:
    These Application/Analogous Situation questions closely resemble Parallel Reasoning questions in Logical Reasoning. We want to find the answer choice that is structurally similar to the element we're asked to analogize. The correct answer won't have the same subject matter as the passage; instead, it will feature similar characteristics or themes as the element from the passage. Therefore, we should start by reviewing the key features of the element we're asked to parallel.

    In this case, we're asked to find an answer choice about volatile oils most analogous to the "situation involving peptides." So, what are the key features of that situation? In the passage, Hu and Belcher were studying peptides for one reason, and then they set out to see if they could use peptides to build computer chips, eventually synthesizing new peptides for that purpose.

    Abstracting, we should look for an answer where researchers study volatile oils in one context before shifting their research to use volatile oils to solve a problem in another context, with the eventual synthesis of new versions of volatile oils.

    This anticipation may sound rather broad, but we want our anticipation to be very general for these questions. This will help us assess the elements or themes of the answer choices independent of their subject matter.

    Answer Choice Explanation:
    Does this reflect the key characteristics of Belcher and Hu's research into peptides?

    Yes, this gets much closer than every other answer choice we read. The research here starts with a natural compound with a natural purpose (antifungal for trees, which mirrors Belcher's peptide in abalone shells). This compound is then applied to a problem in another context (human medicine, which mirrors technology) through the synthesis of further versions of the compound (which mirrors the evolution Belcher and Hu spurred). That's the same generalized situation as the passage, so this is the correct answer.

    Key Takeaway:
    These questions are very much like Parallel Reasoning questions, so make sure you have an abstract view of what you're looking for before heading to the answers!

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