Reading comp PrepTest 155 · Section 3 · Question 20
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
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.
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 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)
- Cause-and-effect relationship:
- 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)
- Author's view:
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
The primary role of
Remaining source text redacted.
Why the credited answer is right
Credited answer: B
The notes below walk through why it fits the stem and how to eliminate the rest.
Question Type
Science
Answer choices
-
Awhy research of the Remaining source text redacted.
Why choice A is not credited
Does this answer choice say that the first two lines establish the urgency of a problem the researchers discussed throughout the rest of the passage are trying to solve?
No. So experienced test-takers will eliminate this answer choice once they realize it deviates from their anticipation.
Still, this is an understandably attractive choice for many test-takers. This answer choice is trying to get you to think that, in highlighting the growth up until 2000 and before 2010, the passage suggests research like Belcher and Hu's wasn't needed. However, there's no indication that the 2010 "wall" hasn't been known for a while. Additionally, there's a factual issue with this answer choice. The end of the first paragraph notes that people have been studying DNA to solve this problem, so there is already research "of the sort." -
Bthe purpose and importance Remaining source text redacted.
Why choice B matches the stem
Question Type:
Argument Structure/Role of Detail
Strategy Overview:
Review the first two sentences in the passage, consult notes, and choose an answer choice based on your understanding of that reference in the passage's overall argument
Answer Anticipation:
This question asks us why the author inserted the first two sentences into the first paragraph. Unless a detail conflicts with the paragraph's purpose, the author probably mentioned that detail to advance the paragraph's role. So reviewing the first paragraph's role, which we hopefully wrote down in the notes on our scratch paper, will generally reveal why the author included that detail.
In this case, our note for the first paragraph is, "Problem (making computer chips smaller) and one possible solution (using peptides)." Reviewing the first two lines, we'll see that they are directly related to describing the problem. These lines establish the problem that the researchers discussed throughout the rest of the passage were trying to solve, as well as how important of a problem it is — more efficient chips drive economic and technological growth, so hitting a wall would be "unthinkable." Let's find an answer reflecting that.
Answer Choice Explanation:
Does this answer choice say that the first two lines establish the urgency of a problem the researchers discussed throughout the rest of the passage are trying to solve?
Yes! Expert test-takers would select (B) and advance to the next question. After all, we know Hu and Belcher's research addresses a problem outlined in the first two sentences. Since the sentences in question bring up a problem that Hu and Belcher are trying to solve and hint at the urgency in solving that problem, these sentences provide context for why this research is important.
Key Takeaway:
Taking a few moments to note each paragraph's role is a worthwhile investment of time for most test-takers. Doing so helps us read for structure, reinforcing our understanding of the passage. It also makes answering Role of Detail and Role of Paragraph questions much easier. Often, we can find the correct answer simply by consulting our notes for the relevant paragraph. -
Cthe skepticism with which Remaining source text redacted.
Why choice C is not credited
Does this answer choice say that the first two lines establish the urgency of a problem the researchers discussed throughout the rest of the passage are trying to solve?
Nope. Diligent test-takers would consequently eliminate (C).
Besides, the passage never discusses skepticism towards their research, and these opening lines don't come close to supporting this answer. -
Da commonly held viewpoint Remaining source text redacted.
Why choice D is not credited
Does this answer choice say that the first two lines establish the urgency of a problem the researchers discussed throughout the rest of the passage are trying to solve?
Negative. Shrewd test-takers would cross off (D) once they saw it didn't match their anticipation.
Besides, Hu and Belcher aren't arguing against the notion that current methods can't make computer chips smaller — they're trying to develop new methods to solve that problem. -
Ea hypothesis that Belcher Remaining source text redacted.
Why choice E is not credited
Does this answer choice say that the first two lines establish the urgency of a problem the researchers discussed throughout the rest of the passage are trying to solve?
Again, no. As a result, veteran test-takers would remove (E) from contention.
Additionally, Hu and Belcher aren't trying to test whether current methods can create smaller chips — they're trying to test a new method for creating smaller chips.
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