Reading comp PrepTest 121 · Section 2 · Question 16
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: D
The notes below walk through why it fits the stem and how to eliminate the rest.
Question Type
Strategy Overview
Answer Anticipation
Answer choices
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AA child seeking information Remaining source text redacted.
Why choice A is not credited
(A) We are looking for the answer choice that matches the most features of the cosmologists’ approach. How does this one do?
Not well, but this was a very common wrong-answer choice so let’s make sure we know why this one is wrong. The idea of a child seeking information is on the right track, but nothing else seems to match the cosmologists’ approach. There is no pre-written book on dark matter they can acquire to find the answers!
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BA child seeking to Remaining source text redacted.
Why choice B is not credited
(B) We are looking for the answer choice that matches the most features of the cosmologists’ approach. How does this one do?
Not very well, but again this was a very common wrong-answer choice so let’s make sure we know why this one is wrong. Again, like (A), a child seeking something is on the right track, but the cosmologists did not change their final goal once they couldn’t get what they wanted. Instead, when they found that neutrinos had mass, it actually opened the door to more possible solutions.
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CA child hoping to Remaining source text redacted.
Why choice C is not credited
(C) We are looking for the answer choice that matches the most features of the cosmologists’ approach. How does this one do?
It does not match but this was a very common wrong-answer choice so let’s make sure we know why this one is wrong. A child hoping for something is on the right track, but being disappointed with something and then learning to love something else does not quite match what we are looking for. Instead, the child would have needed to get the dog and realize it was great but insufficient, and in the end go out to acquire even more pets.
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DA child seeking money Remaining source text redacted.
Why choice D matches the stem
(D) We are looking for the answer choice that matches the most features of the cosmologists’ approach. How does this one do?
This matches quite well! The cosmologists were looking for an answer to “What is dark matter?” and found a partial answer in neutrinos. This has led them to consider other, similar, elementary particles but they still do not have the full answer yet. One key feature of this answer choice is that the child has come up with some of the money and has a new, related, plan to get the rest of the money, but still does not have it all yet. This is the right answer. Astute test-takers would still want to check and eliminate the last answer choice before selecting this one.
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EA child enjoys playing Remaining source text redacted.
Why choice E is not credited
(E) We are looking for the answer choice that matches the most features of the cosmologists’ approach. How does this one do?
The cosmologists might enjoy the search for answers to tough questions, but there is no parental figure telling them they have to stop searching until they finish some other task. Even though there is evidence that experimentation would help them find their answers, it does not match well.
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Discussion
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Why not D? 2 replies
Started by mikeheath
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Why A is incorrect? 3 replies
Started by mprezzy
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Help please 4 replies
Started by MichelleRod