Reading comp PrepTest 154 · Section 3 · Question 19

Passage

 For nearly a century after the discovery in the 1880s that a bacterium, Vibrio cholerae , causes cholera, scientists believed Remaining source text redacted.
Passage walkthrough
Passage SummaryTopic: Science

Paragraph 1
  • Paragraph note
    • A common scientific belief is discussed, and a question it leaves open is raised
  • Views, minor Meta-Structures, and the author's attitude
    • Common belief - Cholera travels via human hosts (waste into food and water supplies)
    • Question - How do spontaneous outbreaks in areas cholera was eliminated happen?
Paragraph 2.1 (Lines 12-25)
  • Paragraph note
    • A new belief is brought up and skepticism is discussed
  • Views, minor Meta-Structures, and the author's attitude
    • Rita Colwell (1970s) - Claimed to have found cholera in seawater and it can go undetected by common culture tests
    • Skepticism - "No" biologist thought it could live outside of humans, and there were no outbreaks since 1911
Paragraph 2.2 (Lines 25-39)
  • Paragraph note
    • Colwell's hypothesis is put to the test
  • Views, minor Meta-Structures, and the author's attitude
    • Colwell used a new test (antibodies/UV) and found cholera bacteria in bayous that traditional tests missed
Paragraph 3
  • Paragraph note
    • Further studies backing up/expanding on Colwell's hypothesis, and a future course of inquiry
  • Views, minor Meta-Structures, and the author's attitude
    • Tests show bacteria go into sporelike state that can't be detected using traditional tests
    • That state is more survivable
    • Question - What gets them out of sporelike state? Potential answer - Sea-surface temp spikes (e.g., Bay of Bengal)
Main Point:
There is evidence suggesting that Rita Colwell's hypothesis about "viable but nonculturable" cholera bacteria surviving in the ocean and in a sporelike state is correct, as it explains seemingly spontaneous outbreaks of the disease in areas where it has been eradicated.

Key Lines:
Lines 3-6 - Traditional scientific theory is discussed
Lines 9-11 - A question left open by this theory
Lines 12-14 - A new scientist/theory is introduced
Lines 21-24 - More on that theory
Lines 25-30 - The new theory is tested
Lines 40-42 - The new theory is expanded
Lines 49-51 - A question is posed for the new theory
Lines 51-54 - An answer is put forward

Meta-Structure:
Old Theory/New Theory - The old theory concerning the spread of cholera is shown to leave open a question that a new theory answers.

Question/Answer - Two questions are posed. The first (Lines 9-11) is broad and leads to the main point - Colwell's new theory. The second (Lines 49-50) is limited and leads to a hypothesis to be tested under Colwell's theory.

Last Thoughts:
Normally, the Author is a bit more on board with a new theory being presented. Here, there's a mix. She states that Colwell's studies "revealed" some things about V. cholerae (Line 40), but also poses Colwell's water theory as being something that isn't 100% certain ("If, as Colwell believes" in Line 54).

So we need to be careful in selecting answers that don't overshoot the Author's feelings towards Colwell's theory and pick an answer that reflects a certainty that doesn't exist.

Also, note that we split Paragraph 2 up. It was pretty long, and there was a natural breaking point between where Colwell raised her claim and people expressed skepticism, and the specific situation that allowed her to discover evidence for her hypothesis.

Question prompt

Which one of the Remaining source text redacted.
Why the credited answer is right

Credited answer: B

The notes below walk through why it fits the stem and how to eliminate the rest.

Question Type

Science

Answer choices

  1. A
    to identify future directions Remaining source text redacted.
    Why choice A is not credited
    Incorrect. (Line 50; Lines 55-59) The passage does identify a future direction for research—to figure out what wakes up the dormant bacteria. However, it doesn't bring up any obstacles in the way of researching that. In fact, it brings up a possible answer to the question!
  2. B
    to answer a question Remaining source text redacted.
    Why choice B matches the stem
    Correct. Question Type:
    Argument Structure

    Strategy Overview:
    Review our note for the last paragraph and find an answer reflecting it

    Answer Anticipation/Relevant Lines:
    When we work through an RC passage, we should be taking a quick break after each paragraph to note the purpose of it and how it relates to the broader passage. While you don't have to jot down a few notes on this, it can be helpful to get a word or two down.

    Here, we noted that the third paragraph did two things. First, it discussed further studies conducted by Colwell that backed up and expanded on her hypothesis. Second, it brought up a future area where studies could be done (how does the dormant bacterium wake up?). Let's find an answer reflecting this purpose.

    Answer Explanation:
    (Lines 9-11; Lines 40-43; Line 50) The passage starts with a question—how do cholera outbreaks happen? Colwell's hypothesis provides an answer to this, and Paragraph 3 provides studies that further explain her hypothesis, so this paragraph does answer a question from earlier in the passage. It also discusses new evidence (her studies; the Bay of Bengal) that raises a new question (what causes the dormant V. cholerae to awaken?). This answer hits both elements of the paragraph that we identified, so it's the correct answer.

    Key Takeaway:
    You should be thinking about the role of paragraphs as you read through a passage. And the more you do this, the more you'll see that the same roles show up again and again, making it easier and easier to both define that role and anticipate in which direction the passage is heading.
  3. C
    to evaluate the effect Remaining source text redacted.
    Why choice C is not credited
    Incorrect. (Lines 28-34) The innovative methodology is Colwell's new test that uses antibodies and UV. However, there's no discussion of how this methodology will impact future research, or how it could be used to answer the question of how the dormant bacteria awaken.
  4. D
    to offer recommendations concerning Remaining source text redacted.
    Why choice D is not credited
    Incorrect. (Lines 28-34) This answer is very similar to (C), and it's wrong for the same reasons. The antibody/UV test isn't brought up in discussing future research.
  5. E
    to enumerate the effects Remaining source text redacted.
    Why choice E is not credited
    Incorrect. (Lines 40-43) The biological phenomenon that this paragraph is focused on is the dormancy of V. cholerae, but that phenomenon is described in this paragraph, not the second one.

What this tests

Question analytics

Based on historical answer selection rates for this question.

Answer choice distribution

  1. A 11%
  2. B Credited 57%
  3. C 7%
  4. D 4%
  5. E 21%

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