영어 모의고사 (자동 편성)

The human gut hosts trillions of microorganisms ①whose combined genetic material outnumbers that of the human genome itself many times over. Once dismissed as passive hitchhikers, these bacteria are now understood ②to actively shape digestion, regulate immune responses, and even influence the production of chemicals that affect mood and behavior. A microbiome disrupted by antibiotics, poor diet, or chronic stress can leave the gut lining more permeable than it should be, ③allowing substances to leak into the bloodstream that would normally stay contained. Researchers studying this connection have found that transplanting gut bacteria from a healthy donor into a patient can, in some cases, relieve symptoms of certain digestive disorders that conventional medication ④had failed to treat. Still, scientists caution that the microbiome varies enormously between individuals, which means a treatment that restores balance in one person's gut may ⑤does little for someone else's.

Imagine a distant planet identical to Earth in every visible respect, except that the clear liquid its inhabitants call "water" is not H2O but a different compound, XYZ, that happens to look, taste, and behave exactly the same. When an Earthling and a Twin Earthling each say the word "water," they seem to mean the ①same thing, since neither could tell the substances apart without a chemistry lab. Philosopher Hilary Putnam used this scenario to argue that the meaning of a word is not determined solely by what happens inside a speaker's head. Even though the two speakers hold ②opposing thoughts and mental images when they use the word, their statements refer to ③two different substances, because the underlying chemical composition, not personal belief, fixes what a word ultimately picks out. Meaning, Putnam concluded, depends ④partly on the world outside the mind, not merely on the ⑤private mental states of whoever happens to be speaking.

A liver no longer has to sit inside a human body to be studied ①closely. By coaxing stem cells to organize themselves within a nutrient-rich gel, scientists can now grow ②miniature three-dimensional structures called organoids, which reproduce much of the architecture and function of a real organ despite being no larger than a grain of rice. Unlike flat cultures grown on a plastic dish, which ③preserve many of the cues that guide normal development, organoids let cells interact in three dimensions much as they would inside the body, yielding tissue that behaves in strikingly ④realistic ways. This fidelity has made organoids invaluable for testing how a drug affects human tissue before any patient is exposed, sparing researchers much of the ⑤burden of relying on animal models alone.

Imagine rewriting a bacterium's code the way a programmer edits a line of software, and much of what synthetic biology ①promises begins to make sense. Researchers in this field assemble standardized genetic parts into circuits that can be inserted into a cell, instructing it to perform a task that no natural organism would ②carry out. Because these circuits are built from interchangeable parts rather than designed from scratch each time, a circuit tested in one lab can often be reused, with ③minor adjustments, in an entirely different application. Critics note that biological systems ④always behave as predictably as electronic circuits, since a gene inserted into a new cell can interact with existing pathways in unexpected ways, occasionally producing results no engineer intended. Even so, as the catalog of standardized parts keeps expanding, engineers are gaining ⑤confidence to design increasingly complex systems.

Emissions trading, a market-based mechanism for curbing greenhouse gases, allows governments to set an overall limit on carbon output while letting firms trade permits within that limit. Under this system, known as cap-and-trade, companies that cut emissions more ①cheaply than required can sell surplus allowances to firms facing higher reduction costs. Proponents argue that this flexibility lets society reach a given environmental target at the ②lowest overall cost, since abatement shifts toward whoever can achieve it most economically. Critics, however, contend that trading schemes frequently allocate too many permits, a flaw that has historically ③depressed carbon prices and blunted incentives to invest in cleaner technology. For example, early phases of several regional markets granted allowances so generously that permit prices ④collapsed, leaving polluters with little pressure to change their practices. Consequently, many economists now advocate combining trading with a price floor, a minimum permit price that keeps the market from collapsing during weak demand, thereby ⑤undermining the cost-effectiveness for which trading is valued.

As cities have expanded across landscapes once covered with absorbent soil, impervious surfaces have turned stormwater from a resource that recharges groundwater into a hazard that floods streets and carries pollutants into waterways. (A) For example, cities that replaced pavement with permeable alternatives have reported notable reductions in flooding during storms that once overwhelmed sewers. However, engineers caution that green infrastructure cannot entirely replace conventional pipes in dense cores, where heavy runoff still requires structural reinforcement. Consequently, municipalities now regard green and gray infrastructure as complementary systems, each compensating for the other's limitations. (B) Green infrastructure, which mimics the hydrological functions that natural landscapes once performed, offers planners a way to treat the city as a sponge rather than a rigid drainage pipe. (C) Rain gardens, shallow depressions planted with deep-rooted vegetation, are designed to capture runoff from rooftops, allowing it to filter slowly through soil before reaching underground aquifers. Permeable pavement, made of porous materials that let water pass directly through, serves a similar purpose along sidewalks, where asphalt would remain impenetrable.

Extended producer responsibility, a policy requiring manufacturers to bear responsibility for their products even after use, has been adopted by governments seeking to reduce landfill waste. (A) Critics counter that the policy, whatever its theoretical merits, often fails to reduce waste meaningfully unless paired with rigorous enforcement and transparent reporting requirements. For instance, some manufacturers merely pass the added cost of compliance on to consumers, without making substantive changes to how products are designed. (B) Under such schemes, companies must finance the collection and recycling of goods once consumers discard them, rather than leaving municipalities to absorb the cost. Advocates maintain that shifting this burden onto producers creates a powerful incentive to design products that are more durable, easily disassembled, and readily recyclable from the outset. (C) In contrast, jurisdictions that combine producer responsibility with strict eco-design standards and independent audits tend to witness genuine improvements in recyclability. Therefore, policymakers hoping to harness this approach must resist treating it as self-executing and instead invest in oversight that determines whether producers actually change behavior.

Janis identified several warning signs, including an illusion of invulnerability that leads a group to underestimate risk, pressure on dissenters to fall in line, and self-appointed mindguards who shield the group from information that might disrupt its confidence. Even highly capable individuals can make disastrous collective decisions once they are absorbed into a tightly knit group, a phenomenon psychologist Irving Janis termed groupthink. ( ① ) Within cohesive committees, boards, and advisory councils, members often prioritize consensus and group harmony over a rigorous evaluation of alternatives, silencing doubts rather than risking the discomfort of dissent. ( ② ) Sociologists extend this analysis beyond small committees, noting that entire organizations can develop cultures that reward conformity and punish employees who raise inconvenient questions. ( ③ ) Historical inquiries into policy failures and corporate disasters frequently reveal that critical information existed within the organization but never reached decision makers. ( ④ ) This was not because it was hidden, but because no one felt safe enough to voice it aloud. ( ⑤ )

The practical consequence of this precision has been a dramatic acceleration in the pace of genetic research itself. Bacteria have been cutting up invading viral DNA for billions of years, long before any scientist thought to borrow the trick for use in a laboratory. ( ① ) The CRISPR-Cas9 system, as it is now known, relies on a short guide RNA that matches a specific DNA sequence, leading a scissor-like enzyme called Cas9 directly to that exact location in the genome. ( ② ) Once Cas9 arrives at the target site, it slices both strands of the DNA helix, and the cell's own repair machinery rushes in to mend the cut, often introducing a small change in the process. ( ③ ) By supplying the cell with a template during this repair step, scientists can direct that machinery to insert a specific new sequence. ( ④ ) This goes well beyond merely disabling the original gene. ( ⑤ ) What once required years of painstaking work to alter a single gene can now, with a properly designed guide RNA, be accomplished within days.

This puzzling inconsistency is not, as it turns out, a matter of chance. Two patients diagnosed with the same disease and prescribed the same medication can respond in strikingly different ways, one recovering quickly while the other experiences little benefit or even harmful side effects. ( ① ) Precision medicine starts from the observation that this variation often traces back to differences buried in each patient's genome. ( ② ) These differences determine how efficiently a body absorbs, breaks down, or responds to a given drug. ( ③ ) By sequencing a patient's DNA before treatment begins, doctors can increasingly predict which medication is likely to work best and at what dose, replacing a strategy once described as one-size-fits-all with something closer to a tailored fit. ( ④ ) This approach has proven especially valuable in cancer treatment, where tumors from two patients with the same diagnosis may carry entirely different genetic mutations that respond to entirely different drugs. ( ⑤ ) Widespread adoption still faces real obstacles, since genetic sequencing remains expensive in many regions and few doctors have been trained to interpret the flood of genetic data such tests now produce.