Reading comp PrepTest 121 · Section 2 · Question 13
Passage
Passage walkthrough
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)
- Definition
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)
- Definition
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)
- Causality
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)
- Causality
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/AnswerThis 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
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.
Question Type
Strategy Overview
Answer Anticipation
Answer choices
-
AAlthough cosmologists believe that Remaining source text redacted.
Why choice A is not credited
(A) Does this match our anticipation, that neutrinos are a possibility to answer the dark matter question?
No it does not. Although a number of test-takers chose this answer choice so let’s make sure we understand what is wrong. This is a description of the question (or, more accurately, the question leading to the main question) only. We also need to see the author’s answer to that question. An understanding of Meta-Structures can help us avoid these “half-of-the-story” wrong answer choices!
-
BGiven their inability to Remaining source text redacted.
Why choice B is not credited
(B) Does this match our anticipation, that neutrinos are a possibility to answer the dark matter question?
No, and although it is using some of the right words it is actually incorrect—the understanding of gravity is not at issue here, but what is all “missing” matter that is causing all this gravity!
-
CIndirect evidence suggesting that Remaining source text redacted.
Why choice C matches the stem
(C) Does this match our anticipation, that neutrinos are a possibility to answer the dark matter question?
It sure does, although it is more specific. It matches what we are looking for that the others do not—an answer to the question described in the passage and not just the question alone.
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DAfter much speculation, researchers Remaining source text redacted.
Why choice D is not credited
(D) Does this match our anticipation, that neutrinos are a possibility to answer the dark matter question?
No, and it is too specific. Although it is similar (but still factually off) to the experiment that led to the discovery of neutrinos’ mass, it is not the main point of the passage.
-
EAlthough it has been Remaining source text redacted.
Why choice E is not credited
(E) Does this match our anticipation, that neutrinos are a possibility to answer the dark matter question?
No, this is off the mark. Even though it is using the right words, not only has it not been established that neutrinos have mass, but also this mass does support the speculation that neutrinos are a good candidate for the “missing” matter in the universe.
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