Reading Comprehension

PT2 · S1 · P3 · Q19 Water Bugs

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Three basic adaptive responses—regulatory, acclimatory, and developmental—may occur in organisms as they react to changing environmental conditions.

Topic

How organisms—specifically water bugs—adapt to environmental changes, with a focus on reversible and irreversible responses.

Framework

Theme / Example

Main Point

Organisms can adapt to environmental changes through regulatory, acclimatory, and developmental responses; in water bugs, the developmental response determining wing type is an environmentally driven, permanent adjustment rather than a genetic one. *The Most Valuable Sentence appears in the third paragraph: *

P1: Types of Adaptive Responses

This paragraph introduces the three major types of adaptive responses: regulatory (quick, reversible physiological adjustments), acclimatory (slower, reversible structural changes), and developmental (usually permanent, fixed during development).

P2: Developmental Responses in Water Bugs

Here, the passage zooms in on developmental responses—using water bugs as an example—to explain how different generations have different wing types based on their seasonal needs. The summer generation shows two forms (some with normal wings, some with reduced wings), while the overwintering generation always has full wings for dispersing. This dimorphism is a strategy for survival given environmental uncertainties.

P3: Environmental Determination of Wing Type

This paragraph explains that the wing type variation in water bugs is not genetic, but determined by the temperature during egg development—cold temperatures lead to reduced wings, while warm temperatures lead to full wings. All overwintering bugs come from eggs formed in warm temps, ensuring full wings for migration; experimental evidence supports that temperature, not genetics, decides wing form.

19.

According to the passage, the generation of water bugs hatching during the summer is likely to

  1. be made up of equal

    Too Strong: equal

    We expect our summer hatchers to have fully developed wings. In other words, we expect them to be all (or almost all) macropterous. The summer hatchers are called the overwintering generation. The spring hatchers are called the summer generation, and they're the ones that can come out macropterous or micropterous. But even for them, we wouldn't say theres going to be equal numbers of each.

    8% picked this

  2. lay its eggs during the

    Contradicted, if anything

    This answer goes against the 3rd of our available facts. - they live over the winter before breeding in early spring - they have fully developed wings and leave the water in autumn to overwinter in forests - they return in the spring to small bodies of water to lay eggs It would also be weird to say about any water bug that they lay their eggs during winter in order to expose them to cold. We aren't ever told that water bugs intend to expose certain eggs to the cold.

    5% picked this

  3. show a marked inability to

    Opposite

    Since we think that these water bugs have fully developed wings (our 2nd bullet point), we would assume that they have a marked ability to fly from one pond to another. - they live over the winter before breeding in early spring - they have fully developed wings and leave the water in autumn to overwinter in forests - they return in the spring to small bodies of water to lay eggs

    13% picked this

  4. exhibit genetically determined differences in

    Contradicted: genetically determined

    The whole theme of this Theme / Example passage is that for these water bugs, the trait of having fully determined vs. janky wings is NOT genetically determined. It is a developmental response. It is determined by how warm or cold the temperature is surrounding an egg before it hatches.

    19% picked this

  5. Correct

    contain a much greater proportion

    Why this is right

    We're told that the 1st generation, which hatches in the spring and is referred to as the summer generation will have some macropterous and some micropterous water bugs. We're told that the 2nd generation, which hatches in the summer and is referred to as the overwintering generation, will all have fully developed (macropterous) wings. So since all of the summer hatched generation has macropterous wings, whereas some of the spring hatched generation will have micropterous wings, it's safe to say that 100% macropterous in the summer hatchers will be a greater proportion than less-than-100% macropterous in spring hatchers.

    Skill tested: Locate Detail · how this choice captures the passage's function is the move to repeat next time.

    55% picked this

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