Reading comp PrepTest 145 · Section 1 · Question 22
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 passage most strongly
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
Answer choices
-
Aconfidence in its truth
Why choice A is not credited
Incorrect. (Line 14; Lines 41; Line 48; Line 51; lines 55-58) The Author never uses any positive language to describe Steele's theory, either presenting what he says as beliefs and claims, or presenting those skeptical of his work. As such, this answer is way too positive. -
Bindignation at its divergence Remaining source text redacted.
Why choice B is not credited
Incorrect. "Indignation" is way too strong of a negative word, and one that conveys an emotional aspect. The Author is neither this negative nor does she express anger or annoyance at Steele's claims. -
Cdistrust of its novelty
Why choice C is not credited
Incorrect. (Lines 55-58) The other biologists at the end might have this attitude, as they view Steele's explanations as "radical," which is inherently related to novelty, but that's phrased as their view, not the Author's. This answer is too strongly negative, and it conveys a specific criticism that the Author doesn't level against the theory. -
Ddoubt concerning its plausibility
Why choice D matches the stem
Correct. Question Type:
Author's Attitude
Strategy Overview:
Review where the Author's attitude showed up, then find an answer reflecting that attitude
Answer Anticipation/Relevant Lines:
As we've noted before, the Author is largely absent from this passage. Whenever she talks about what Steele is claiming, she frames it as something that he and his colleagues "believe" (Line 41) or "claim" (Line 14; Line 48; 51). She also introduces the view of biologists who are skeptical of this explanation (Lines 55-58).
So the Author neither accepts it as true or rules it out. She's skeptical of the claims and doesn't think that Steele has proven anything, but she also doesn't think that it can be dismissed out of hand. Let's find an answer reflecting this attitude.
Answer Explanation:
(Line 14; Lines 41; Line 48; Line 51; lines 55-58) This is one of those answers that really requires you to use the technical definition of words. "Doubt" simply conveys that someone isn't convinced of something, which the Author definitely isn't of Steele's hypothesis since she uses words like "believe" and "claim" to talk about what he says. And "plausible" means seeming reasonable or probable, which the Author also believes since she clearly doesn't think this is the most likely explanation. Doubt of plausibility is also reflected in the tone of her question in the last paragraph—"does it ever actually occur?" Those adverbs are used to convey a bit of disbelief in whether it actually occurs. This answer is therefore correct.
Key Takeaway:
For these Author's Attitude questions, it's really important to focus on the first word in the answer choices, and it's even more important to think about the precise definition of a word. While "doubt" might be fairly strongly negative with how most people use it, it only conveys uncertainty, which this passage had in spades. -
Edismay at its lack Remaining source text redacted.
Why choice E is not credited
Incorrect. (Line 39; Lines 46-47) The Author does call Steele's argument speculative and based on circumstantial evidence. However, there are two issues here. First, "dismay" doesn't capture her opinion, as it conveys an emotional reaction akin to distress, and the Author simply analyzes Steele's argument. Second, just because an argument is speculative and based on circumstantial evidence doesn't mean it isn't rigorous—Steele might have gone to great lengths to come up with this evidence since, after all, all evidence of evolutionary mechanisms are circumstantial (Lines 46-47). She even notes that his evidence was found all over DNA, which seems like it might take quite a bit of work to collect.
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