High School Reading: Grades 9-10 Quiz: Analyzing Idea Development

The story of penicillin is often told as a tale of pure luck. In 1928, Alexander Fleming returned from vacation to find that a mold had contaminated one of his petri dishes, killing the surrounding bacteria. He named the substance penicillin and published his findings the following year. Yet the narrative of accidental discovery obscures the far longer road to a usable drug.

Fleming himself abandoned penicillin research within a few years, unable to purify the compound in stable quantities. It sat in the scientific literature, largely ignored, for nearly a decade. Only in 1939 did Howard Florey and Ernst Chain, working at Oxford, revive the project—not because they anticipated a miracle drug, but because they were systematically surveying antibacterial substances for a research program.

Their team's breakthrough was not conceptual but industrial. They developed freeze-drying techniques to concentrate penicillin and painstakingly tested it on mice. When wartime demand exploded, American pharmaceutical firms, drawing on fermentation methods developed for other industries, scaled production from milligrams to tons.

The lesson, then, is not that great discoveries fall from the sky. It is that a chance observation becomes a medicine only through a chain of unglamorous labor—purification, testing, scaling—performed by people whose names rarely appear in the story.

How does the author develop the analysis across the passage?

In 1854, when cholera swept through the Soho district of London, the prevailing theory held that the disease spread through "miasma"—foul-smelling air rising from filth. Physician John Snow doubted this. He suspected contaminated water instead, and he set out to test his hypothesis in the middle of an outbreak.

Snow began by mapping the deaths, plotting each fatal case on a street diagram of the neighborhood. A cluster emerged around the Broad Street pump. He then interviewed families of the deceased and cross-checked which pump they had used. Cases that at first seemed anomalous—a woman who died miles away, workers who lived near a different pump but were spared—resolved on inspection: the distant woman had water shipped from Broad Street because she preferred its taste; the spared workers drank from a brewery well.

Snow persuaded local authorities to remove the pump handle. The outbreak, already waning, subsided further. Miasma theory did not die immediately; it would persist for decades. But Snow had demonstrated something new—that a disease's cause could be traced by patient, spatial detective work, one case at a time.

How does the sequence of events in the passage develop the author's analysis?

Journalism schools once taught "objectivity" as the profession's core virtue. A reporter was to gather facts, present multiple sides, and keep personal views out of the copy. This ideal, though never fully realized, shaped American newsrooms for most of the twentieth century.

In recent years, a growing chorus of journalists has pushed back. They argue that "balance" between well-supported claims and fringe positions distorts reality more than it reveals it. To give equal weight to climate scientists and climate deniers, for example, is not neutrality but a false equivalence that misleads readers about the state of the evidence.

Defenders of the older model reply that abandoning objectivity risks turning journalism into advocacy, indistinguishable from opinion writing. Readers already distrust the press; a more openly partisan journalism would only accelerate the decline.

Both sides, notably, share a concern for accuracy—they disagree about which practices actually produce it. That shared premise, more than the loud disagreements, may point toward a path forward: not the abandonment of objectivity, but its redefinition around evidentiary weight rather than symmetrical presentation.

How does the author structure the discussion of journalistic objectivity?

In 1962, Rachel Carson published Silent Spring, an indictment of the pesticide DDT and, more broadly, of a chemical industry that had grown accustomed to operating without scrutiny. The book was serialized in The New Yorker before it appeared in hardcover, reaching millions of readers who might otherwise have skipped a work of environmental science.

Carson's argument was carefully layered. She opened with a fable—a fictional American town where spring arrives without birdsong—that made the abstract stakes vivid. She followed with dense chapters of chemistry, ecology, and epidemiology, meticulously footnoted. She closed with a call not for the abandonment of pest control but for restraint, humility, and the pursuit of biological alternatives.

The industry response was fierce. Chemical companies dismissed Carson as hysterical, unscientific, a spinster with a grudge against progress. But her documentation held up. Within a decade, DDT was banned for agricultural use in the United States, and a new regulatory framework—embodied in the Environmental Protection Agency—had emerged.

What Silent Spring accomplished was not the discovery of new facts. It was the assembly of scattered evidence into a case the public could not ignore.

The final paragraph most directly serves what function in the author's analysis?

The concept of the "food desert"—a neighborhood without access to fresh, affordable groceries—entered public discourse in the early 2000s. Policymakers embraced it. If poor health in low-income communities stemmed from geography, the solution seemed clear: incentivize supermarkets to open in underserved areas.

Billions of dollars later, the results have been humbling. Studies of neighborhoods where new supermarkets opened found only modest changes in what residents actually ate. Families who had shopped at distant stores continued shopping there, or bought largely the same items closer to home. The predicted health improvements did not materialize.

Researchers have since revised the framework. Access matters, they now argue, but so do price, time, cooking facilities, cultural preferences, and the marketing pressures children face at school and on screens. A supermarket in the neighborhood does not, by itself, make broccoli cheaper than chips or dinner faster to prepare than fast food.

The "food desert" metaphor, useful as a rallying cry, may have oversimplified the problem it named. What began as a geographic question has been forced open into an economic, cultural, and structural one.

The author's analysis proceeds primarily by:

When cities began installing LED streetlights in the early 2010s, the appeal seemed obvious: LEDs use roughly half the electricity of the sodium-vapor lamps they replaced, and they last far longer. Environmental groups initially cheered the switch. Los Angeles, an early adopter, projected millions in annual savings.

But within a few years, a countercurrent emerged. Astronomers reported that the new lights, which emit a broader spectrum of white light, were scattering more effectively in the atmosphere, brightening night skies even where fewer photons were being produced. The American Medical Association issued a warning in 2016 about the effects of blue-rich light on human sleep cycles. Ecologists documented disruptions to nocturnal insects and migrating birds.

Cities responded unevenly. Some, like Tucson, dimmed their new lights and installed shielding. Others pointed to the energy savings and continued installations unchanged. The debate has not resolved so much as revealed a deeper problem: efficiency gains in one dimension can generate costs in dimensions no one measured beforehand.

The author structures the passage primarily to develop which idea?

The extinction of the passenger pigeon is often told as a straightforward story of overhunting. In the early nineteenth century, flocks darkened the skies of North America for hours as they passed; by 1914, the last individual died in a Cincinnati zoo. The commercial hunting of the birds—shipped by railcar to eastern markets—is well documented and undeniably central.

But hunting alone cannot fully explain the collapse. Passenger pigeons depended on massive communal roosts for successful breeding; below some threshold of flock size, their reproductive strategy simply failed. The birds were, in ecological terms, obligate colonial breeders. Once populations fell past a certain point, extinction became likely even without further hunting.

Deforestation compounded the problem. The vast beech and oak forests that fed the flocks were being cleared for agriculture at unprecedented rates. Habitat loss did not need to kill every pigeon; it only needed to prevent recovery.

The pigeon's fate, then, was overdetermined. Any one of these pressures might have been survivable; together, they created a trap from which no escape was possible.

How does the author unfold the explanation of the passenger pigeon's extinction?

For decades, economists treated the minimum wage as a settled question. Basic supply-and-demand models predicted that raising the price of labor above its market rate would reduce employment. Textbooks presented this as nearly self-evident, and empirical studies through the 1970s generally supported the prediction.

Then came the 1994 study by David Card and Alan Krueger. Comparing fast-food employment in New Jersey (which raised its minimum wage) with neighboring Pennsylvania (which did not), they found no significant job losses in New Jersey—and possibly a slight increase. The finding was heretical. Critics attacked the methodology; defenders pointed out that similar patterns appeared in other natural experiments.

A generation of subsequent research has not produced consensus, but it has shifted the terrain. Even economists skeptical of Card and Krueger now concede that modest increases in the minimum wage produce, at most, small employment effects. The debate has moved from whether such increases destroy jobs to how large an increase can be absorbed before the classical predictions reassert themselves.

How does the author unfold the analysis of the minimum-wage debate?