Reading comp PrepTest 121 · Section 2 · Question 15

Passage

Questions 13-19  .        According to the theory of gravitation, every  . particle of matter in the universe attracts every Remaining source text redacted.
Passage walkthrough
Passage Summary

Topic: Science


Paragraph 1

  • Paragraph note
    • There seems to be a lot more gravity in the universe than observable bodies exerting gravity, so scientists hypothesize that “dark matter” accounts for the “missing,” unobservable, mass
  • Views, minor Meta-Structures, and the author's attitude
    • Definition
      • Theory of gravitation: every particle of matter attracts every other with force that increases with mass or closeness (sentence one)
      • Cosmologists: scientists who study the universe (sentence three)
      • Dark matter: the “something else” exerting the gravitational force necessary to shape the universe (sentences three and four)
    • Causality
      • Gravitation shapes the structures of stars, galaxies, entire universe (sentence two) (also a List)
    • List
      • Of observable matter: stars, dust, miscellaneous debris (sentence three)
    • Author attitude: “but,” “have attempted,” “seems to be” (sentence three)

Paragraph 2

  • Paragraph note
    • What is dark matter? Possibly neutrinos, but without mass it is unlikely
  • Views, minor Meta-Structures, and the author's attitude
    • Definition
      • Neutrinos: elementary particles created as by-products of nuclear fusion, radioactive decay, or catastrophic collisions between other particles, which are possibly dark matter (sentence two), by far the most numerous kind of particles in the universe (sentence three); long assumed to have no mass (sentence four)
    • Causality
      • Without mass, matter cannot exert gravitational force, and without such force, it cannot induce coherence (sentence five)
    • Author attitude: “more attractive” (sentence two), “however” (sentence four)

Paragraph 3

  • Paragraph note
    • Lab experiment on oscillation provides evidence that suggests neutrinos have mass
  • Views, minor Meta-Structures, and the author's attitude
    • Causality
      • Research on oscillation leads to new idea that neutrinos may have mass (sentences one and two); experiment of generating one neutrino type and then finding evidence it oscillated into another led to evidence of neutrino mass (sentence four)
    • Definition
      • Oscillation: long theorized but never observed phenomenon whereby each of the three neutrino types can turn into another type (sentence two)
    • Author attitude: “suggests” (sentence one)

Paragraph 4

  • Paragraph note
    • Neutrinos having mass would account for some of the proposed dark matter in the universe and lead to a better understanding of how elementary particles hold the universe together
  • Views, minor Meta-Structures, and the author's attitude
    • Causality
      • Even if neutrinos have very little mass, there are so many neutrinos that it would add up to a lot of mass (sentence one)
      • This finding adds to our understanding of the role elementary particles play in holding the universe together (sentence five)
    • Author attitude: “while slight,” “a lot,” “especially” (sentence one); “still;” “could only” (sentence two); “nevertheless,” “enough,” “alter,” (sentence three); “in fact,” (sentence four)

Main Point:

The finding that neutrinos have mass makes it possible that some dark matter is neutrinos, which helps us understand the universe better and find the rest of the “missing” matter

Key Lines?

P2, S1 - Question

P2, S2 - Possible answers mentioned

P3, S1 - Evidence for author’s answer

P4, S5 - Answer is only partial

Meta-Structure?Question/Answer

This passage utilizes a Question/Answer Meta-Structure, in which the explicit question, “What is dark matter?” is posed and the rest of the passage sets out to answer it. Interestingly, the first paragraph gives some preliminary questions (including, where is all the missing matter making the universe coalesce?) that lead to this main question, and because of this, some test-takers may see this as a Phenomenon/Explanation Meta-Structure Passage (with the phenomenon being something like “the universe seems to behave as if it has much more matter than we can observe”). However, because there is an explicit question posed it is best to see it as a Question/Answer passage. Either way, the main point of the passage would come out very similarly, which would be the author’s answer to the question (or the author’s preferred explanation for the phenomenon), which is that the finding that neutrinos have mass makes it possible that some dark matter is neutrinos, which helps us understand the universe better and find the rest of the “missing” matter

Definition

Even if it is not a true Minor Meta-Structure, this passage makes frequent use of definitions and are key to understanding the passage and its use of terms such as dark matter, neutrinos, oscillation, gravity, and more. Even if we cannot fully comprehend all of these terms, just understanding that it is a new term that is being defined by the author can help us prepare for the questions and score well.

Causality

This passage makes extensive use of the Causality Minor Meta-Structures as it shows how different aspects and forces in the universe affect each other, and how experiments directly and indirectly lead to results that can alter our understanding of the universe. This in turn can lead to more experiments and more understanding. Making a note of these cause and effect relationships, whether mentally or physically highlighting them or noting it on them on note paper, will help us understand and recall key features of these Causality Minor Meta-Structures and be ready for the questions.

Last Thoughts?

Using Meta-Structures is a great tool for understanding reading comprehension passages on the LSAT, especially in situations such as this. Some passages can seem dense or too science-y to really “get” but taking a big step back and seeing that there is a question, and then an answer (even if it can be hard to fully understand the question and the answer!) really helps us comprehend the passage and prepare for the questions.

Question prompt

Based on the passage, Remaining source text redacted.
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.

Question Type

Science

Strategy Overview

Review the main point, and use notes or highlighted/underlined text in the passage to recall the author’s attitude, and find the answer that best reflects your understanding of the main point/author’s attitude

Answer Anticipation

This question asks us about the author's view, but doesn't provide any insight into the topic of the correct answer or where the supporting information might show up in the passage. This means the correct answer is likely to relate back to the author's main point. As such, we'll need to rely on our big-picture understanding of the passage to answer this question. We should start by reminding ourselves of the main point (either by reviewing what we said after reading the passage or by rereading our answer to the main point question), which here was that neutrinos have mass makes it possible that some dark matter is neutrinos, which helps us understand the universe better and find the rest of the “missing” matter.. We can also review any notes about the author's attitude or any text we highlighted because it expressed the author's opinion. After doing that, we can head to the answer choices, tabling those that don't line up with the main point. For those answer choices that conform to the author’s main point, we'll use our notes and the passage to see if it's correct.

Answer choices

  1. A
    Observable matter constitutes at Remaining source text redacted.
    Why choice A is not credited

    (A) No, the first paragraph states that at least 90% of the mass of the universe is “missing” or un-observerable.

  2. B
    Current theories are incapable Remaining source text redacted.
    Why choice B is not credited

    (B) Many students incorrectly selected this answer choice, so let’s take a look at why it is wrong. Even though it is true that scientists are unable to identify what dark matter is made of, and where 90% of the universe “went,” the theory of gravity is not in question. The first sentence of the passage explains the theory of gravity. The rest of the passage does not question the theory of gravity but instead how there is so much gravitational force even though there does not seem to be enough mass! In other words, given that gravity is the force causing all particles to attract each other, where is the mass causing all the gravity in the first place?

  3. C
    The key to the Remaining source text redacted.
    Why choice C is not credited

    (C) Incorrect. One key to the dark matter problem is the finding that neutrinos have mass at all, but the exact amount of mass is not as important.

  4. D
    It is unlikely that Remaining source text redacted.
    Why choice D matches the stem

    (D) Correct. Though it is a bit tricky, the author explicitly states that the theory of gravitation explains what we observe in the universe and is not up for debate, we just do not know what is causing all this gravity. Instead of questioning the theory of gravity itself, cosmologists are asking the question, “where is all the missing mass?” or, “what is dark matter?”

  5. E
    Neutrinos probably account for Remaining source text redacted.
    Why choice E is not credited

    (E) Incorrect. Neutrinos may account for some of the missing mass, but the author explicitly states that neutrinos could only account for about 20% of the missing mass, with another 80% left to be “found.”

What this tests

Question analytics

Based on historical answer selection rates for this question.

Answer choice distribution

  1. A 6%
  2. B 36%
  3. C 8%
  4. D Credited 44%
  5. E 6%

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Discussion

  • Why is B wrong? 1 reply

    Started by jingjingxiao11111@gmail.com

  • Answer Choice B 1 reply

    Started by gmaramara

  • Question 39 1 reply

    Started by Sidra