PrepTest 145
[lcid:3676] Prep Test 145 LSAT — Reading Comp — S1
Reading comp
Passage
. The French biologist Jean-Baptiste de Lamarck . (1744–1829) outlined a theory of evolutionary change . in 1809, 50 years
Remaining source text redacted.
Passage walkthrough
Passage SummaryTopic: Science
Paragraph 1
While biologists remain skeptical, Steele and others have proposed a Lamarckian means by which learned immunity could be passed down to the next generation.
Key Lines:
Lines 12-16 - The hypothesis to be explored is introduced
Lines 17-21 - Questions are presented (relevant to Steele's hypothesis)
Lines 24-29 - An answer is presented
Lines 34-38 - Another question is asked (directly related to Steele's hypothesis)
Lines 41-43 - Steele's answers presented
Lines 44-45 - Another question is asked (about Steele's hypothesis)
Lines 48-51 - Steele's answer/evidence is noted
Lines 55-58 - Skepticism towards Steele is noted
Meta-Structure:
Question/Answer - This passage has a Question/Answer structure, but it's a little different than other passages with that structure. Instead of having a central question that the passage attempts to answer, this one walks through a series of questions, each which has at least one answer presented to it. As such, we can't rely on the questions and answers to define the main point—we need to infer that main point by bringing all the questions together.
Old Theory/New Theory - Much like this passage doesn't have a traditional Question/Answer structure, it doesn't have a traditional Old Theory/New Theory structure. Normally, there would be an old theory that's being supplanted by a new one, and the Author's thoughts on the new theory define the main point. Here, there's an old theory (Lamarckism) that's replaced by a new one (Darwinism), but then some scientists try to revive the old theory (at least with respect to a certain area—immune systems), but there's still a debate over it.
Last Thoughts:
This is a tough passage in that it brings up genes, DNA, and RNA. But remember—you don't need to know any science for the LSAT! Any science they want you to know, they've written into the passage. So focus on the Question/Answer structure, and the viewpoints, and you'll be fine!
Also, note that the Author doesn't take sides in this debate! She presents Steele's view/evidence, and she presents the skeptical biologists who aren't swayed by Steele's argument, but she never gives any indication as to which side she thinks is more persuasive.
Paragraph 1
- Paragraph note
- A theory is outlined, ridiculed, and potentially redeemed
- Views, minor Meta-Structures, and the author's attitude
- Lamarck - Pre-Darwin, said animals adapt to environment and pass on
- Biologists - That's ridiculous
- Steele - Lamarckism happens in the immune system
- Paragraph note
- A question is posed and answered
- Views, minor Meta-Structures, and the author's attitude
- Question - How does the immune system adapt to so many and new diseases?
- Answer - One type of cell's RNA mutates a lot and gets tested against new diseases until one works
- Paragraph note
- Process/Question - How can this RNA then become DNA and get passed on?
- Views, minor Meta-Structures, and the author's attitude
- Process - Reverse transcription - RNA alters DNA to have disease fighting ability
- Question - How does this get passed on?
- Answer (Steele) - Viruses carry DNA to reproductive cells to pass on (theoretical, but based on known processes)
- Paragraph note
- A question is asked, evidence is presented, and a disagreement is noted
- Views, minor Meta-Structures, and the author's attitude
- Question - Does Steele's process actually happen?
- Author - Can "never" observe directly; must use circumstantial evidence
- Steele - Yes, and we have evidence in genes
- Other biologists - Probably not, there are less radical explanations
While biologists remain skeptical, Steele and others have proposed a Lamarckian means by which learned immunity could be passed down to the next generation.
Key Lines:
Lines 12-16 - The hypothesis to be explored is introduced
Lines 17-21 - Questions are presented (relevant to Steele's hypothesis)
Lines 24-29 - An answer is presented
Lines 34-38 - Another question is asked (directly related to Steele's hypothesis)
Lines 41-43 - Steele's answers presented
Lines 44-45 - Another question is asked (about Steele's hypothesis)
Lines 48-51 - Steele's answer/evidence is noted
Lines 55-58 - Skepticism towards Steele is noted
Meta-Structure:
Question/Answer - This passage has a Question/Answer structure, but it's a little different than other passages with that structure. Instead of having a central question that the passage attempts to answer, this one walks through a series of questions, each which has at least one answer presented to it. As such, we can't rely on the questions and answers to define the main point—we need to infer that main point by bringing all the questions together.
Old Theory/New Theory - Much like this passage doesn't have a traditional Question/Answer structure, it doesn't have a traditional Old Theory/New Theory structure. Normally, there would be an old theory that's being supplanted by a new one, and the Author's thoughts on the new theory define the main point. Here, there's an old theory (Lamarckism) that's replaced by a new one (Darwinism), but then some scientists try to revive the old theory (at least with respect to a certain area—immune systems), but there's still a debate over it.
Last Thoughts:
This is a tough passage in that it brings up genes, DNA, and RNA. But remember—you don't need to know any science for the LSAT! Any science they want you to know, they've written into the passage. So focus on the Question/Answer structure, and the viewpoints, and you'll be fine!
Also, note that the Author doesn't take sides in this debate! She presents Steele's view/evidence, and she presents the skeptical biologists who aren't swayed by Steele's argument, but she never gives any indication as to which side she thinks is more persuasive.
Question prompt
The author most likely
Remaining source text redacted.
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
Science
Answer choices
-
Adistinguish it from mutations Remaining source text redacted.
Why choice A is not credited
Incorrect. (Lines 24-25) The passage notes that the "typos" are the most common type of mutation that happens when immune cells are trying to find something that works against a virus. As such, these mutations are adaptive, since they're adapting cells to address a specific threat. -
Bcharacterize it as relatively Remaining source text redacted.
Why choice B is not credited
Incorrect. (Lines 27-29) These "typo" mutations are noted as allowing the immune system to test things out until it finds something that works, so they're not inconsequential—they're the basis for our ability to fight off new diseases! -
Cindicate that it is Remaining source text redacted.
Why choice C matches the stem
Correct. Question Type:
Argument Structure/Meaning in Context
Strategy Overview:
Review the purpose of the paragraph including the line in question, then use the role of it along with the context of the immediate section including Line 25 to determine the purpose behind the word choice
Answer Anticipation/Relevant Lines:
Line 25 is included in Paragraph 2, and we said the purpose of that paragraph was to pose a question and answer it—namely, how does the immune system adapt to diseases? Line 25 is a part of the answer to that, so we have a big picture view of the purpose of this line.
Diving in, we can see that the answer to how the immune system works is that there's a type of cell in the immune system that mutates frequently. It then talks about one specific type of mutation, referring to it as a "typo" when DNA is turned into RNA.
DNA, RNA, and genes are above most of our heads, but we all understand what a "typo" is! So the language here is meant to take a complex topic and make it easier for us to understand. What topic is that? An error that happens "when a cell's DNA is transcribed into RNA." So the inclusion of "typo" here is meant to make it easier for us to understand that this line is talking about something getting messed up when it's being copied over from the original. Let's find an answer reflecting that.
Answer Explanation:
(Lines 24-26) The topic of this paragraph is pretty complex—how the immune system's DNA, RNA, and proteins adapt to fight off new diseases. In this sentence, it's talking about how DNA is "transcribed" into RNA—how it's copied from the one form to another (even if you don't know "transcribe" in the scientific context, it's still a common word outside of it, so the LSAT expects you to know what it means). The Author here uses "typo" to use more common language to highlight that she's talking about this transcription having an error in it—an imperfect copy. This answer is therefore correct.
Key Takeaway:
When there's a word being used in a scientific context that also has a common meaning, one of two things will be true. Either the meaning in the scientific context is related strongly to the other meaning, in which case you should treat it as having that meaning. Or the meaning in the scientific context won't be related to the other meaning, and the word will be in quotation marks (expect a question about its meaning) or you'll be provided with a definition of it. Here, "transcribed" didn't have quotations or a definition provided, so you should have treated it as having a meaning similar to its non-scientific usage. -
Demphasize that it is Remaining source text redacted.
Why choice D is not credited
Incorrect. (Lines 24-29) There's no indication that anyone or anything is overlooking these mutations. In fact, the passage notes that these mutations result in immunity, which is a big deal! -
Esuggest an analogy between Remaining source text redacted.
Why choice E is not credited
Incorrect. This is a tempting answer! The Author is using "typo" as a type of analogy to make it easier for us to understand what's going on. However, "typos" aren't really involved in textual analysis, which would care about the meaning of a text, not random errors that happened during copying.
What this tests
Discussion
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C 1 reply
Started by tomgbean