SAT April 26

What that means is that while conventional agriculture is more efficient—sometimes much more efficient—than organic farming, there are trade-offs with each. So an ideal global agriculture system, in the views of the study’s authors, may borrow the best from both systems, as Jonathan Foley of the University of Minnesota explained: “The bottom line? Today’s organic farming practices are probably best deployed in fruit and vegetable farms, where growing nutrition (not just bulk calories) is the primary goal. But for delivering sheer calories, especially in our staple crops of wheat, rice, maize, soybeans and so on, conventional farms have the advantage right now.” “Looking forward, I think we will need to deploy different kinds of practices (especially new, mixed approaches that take the best of organic and conventional farming systems) where they are best suited—geographically, economically, socially, etc.”

According to Foley, an “ideal global agriculture system”:

• A) focuses primarily on yield percentages and global markets.

• B) considers multiple factors in the selection of farming techniques.

• C) weighs the economic interests of farmers against the needs of consumers.

• D) puts the nutritional value of produce first and foremost

Maguire and her team thought it was possible that they might discover anatomical differences in the brains of the memory champs, evidence that their brains had somehow reorganized themselves in the process of doing all that intensive remembering. But when the researchers reviewed the imaging data, not a single significant structural difference turned up. The brains of the mental athletes appeared to be indistinguishable from those of the control subjects. What’s more, on every single test of general cognitive ability, the mental athletes’ scores came back well within the normal range. The memory champs weren’t smarter, and they didn’t have special brains. But there was one telling difference between the brains of the mental athletes and the control subjects: When the researchers looked at which parts of the brain were lighting up when the mental athletes were memorizing, they found that they were activating entirely different circuitry. According to the functional MRIs [fMRIs], regions of the brain that were less active in the control subjects seemed to be working in overdrive for the mental athletes.

According to the passage, when compared to mental athletes, the individuals in the control group in Maguire’s second study

• A) showed less brain activity overall.

• B) demonstrated a wider range of cognitive ability.

• C) exhibited different patterns of brain activity.

• D) displayed noticeably smaller hippocampal regions.

MIT business scholars Erik Brynjolfsson and Andrew McAfee have argued that impressive advances in computer technology—from improved industrial robotics to automated translation services—are largely behind the sluggish employment growth of the last 10 to 15 years. Even more ominous for workers, they foresee dismal prospects for many types of jobs as these powerful new technologies are increasingly adopted not only in manufacturing, clerical, and retail work but in professions such as law, financial services, education, and medicine. 

According to Brynjolfsson and McAfee, advancements in technology since approximately the year 2000 have resulted in

• A) low job growth in the United States.

• B) global workplace changes.

• C) more skilled laborers in the United States.

• D) no global creation of new jobs

Scientists do not know how the birds find that aerodynamic sweet spot, but they suspect that the animals align themselves either by sight or by sensing air currents through their feathers. Alternatively, they may move around until they find the location with the least resistance. In future studies, the researchers will switch to more common birds, such as pigeons or geese. They plan to investigate how the animals decide who sets the course and the pace, and whether a mistake made by the leader can ripple through the rest of the flock to cause traffic jams.

What is a main idea of the paragraph?

• A) Different types of hierarchies exist in each flock of birds.

• B) Mistakes can happen when long-winged birds create a V formation.

• C) Future research will help scientists to better understand V formations.

• D) Long-winged birds watch the lead bird closely to keep

While I wasn’t around to witness the initial rejection of Higgs’s proposal in 1964 (well, I was around, but only barely), I can attest that by the mid-1980s, the assessment had changed. The physics community had, for the most part, fully bought into the idea that there was a Higgs field permeating space. In fact, in a graduate course I took that covered what’s known as the Standard Model of Particle Physics (the quantum equations physicists have assembled to describe the particles of matter and the dominant forces by which they influence each other), the professor presented the Higgs field with such certainty that for a long while I had no idea it had yet to be established experimentally. On occasion, that happens in physics. Mathematical equations can sometimes tell such a convincing tale, they can seemingly radiate reality so strongly, that they become entrenched in the vernacular of working physicists, even before there’s data to confirm them. 

Which statement best describes the technique the author uses to advance the main point of the paragraph?

• A) He recounts a personal experience to illustrate a characteristic of the discipline of physics.

• B) He describes his own education to show how physics has changed during his career.

• C) He provides autobiographical details to demonstrate how Higgs’s theory was confirmed.

• D) He contrasts the status of Higgs’s theory at two time periods to reveal how the details of the theory evolveD

In one recent study, Nina Theis and Lynn Adler took on the specific problem of the Texas gourd—how to attract enough pollinators but not too many beetles. The Texas gourd vine’s main pollinators are honey bees and specialized squash bees, which respond to its floral scent. The aroma includes 10 compounds, but the most abundant—and the only one that lures squash bees into traps—is 1,4-dimethoxybenzene. Intuition suggests that more of that aroma should be even more appealing to bees. “We have this assumption that a really fragrant flower is going to attract a lot of pollinators,” says Theis, a chemical ecologist at Elms College in Chicopee, Massachusetts. But, she adds, that idea hasn’t really been tested—and extra scent could well call in more beetles, too.

The author indicates that it seems initially plausible that Texas gourd plants could attract more pollinators if they

• A) did not have aromatic flowers.

• B) targeted insects other than bees.

• C) increased their floral scent.

• D) emitted more varied fragrant compounds.

Of course, that’s not how most environmentalists regard their arugula [a leafy green]. They have embraced organic food as better for the planet—and healthier and tastier, too—than the stuff produced by agricultural corporations. Environmentalists disdain the enormous amounts of energy needed and waste created by conventional farming, while organic practices—forgoing artificial fertilizers and chemical pesticides—are considered far more sustainable. Sales of organic food rose 7.7% in 2010, up to $26.7 billion—and people are making those purchases for their consciences as much as their taste buds. 

Which choice best reflects the perspective of the “environmentalists” on conventional agriculture?

• A) It produces inferior fruits and vegetables and is detrimental to the environment.

• B) It is energy efficient and reduces the need to convert wilderness to farmland.

• C) It is good for the environment only in the short run.

• D) It depletes critical resources but protects wildlife habitats

After her groundbreaking study of London cabbies, Maguire decided to turn her attention to mental athletes. She teamed up with Elizabeth Valentine and John Wilding, authors of the academic monograph Superior Memory, to study ten individuals who had finished near the top of the World Memory Championship. They wanted to find out if the memorizers’ brains were—like the London cabbies’—structurally different from the rest of ours, or if they were somehow just making better use of memory abilities that we all possess.

Which question was Maguire’s study of mental athletes primarily intended to answer?

• A) Does the act of memorization make use of different brain structures than does the act of navigation?

• B) Do mental athletes inherit their unusual brain structures, or do the structures develop as a result of specific activities?

• C) Does heightened memorization ability reflect abnormal brain structure or an unusual use of normal brain structure?

• D) What is the relationship between general cognitive ability and the unusual brain structures of mental athletes?

The Venus flytrap [Dionaea muscipula] needs to know when an ideal meal is crawling across its leaves. Closing its trap requires a huge expense of energy, and reopening the trap can take several hours, so Dionaea only wants to spring closed when it’s sure that the dawdling insect visiting its surface is large enough to be worth its time. The large black hairs on their lobes allow the Venus flytraps to literally feel their prey, and they act as triggers that spring the trap closed when the proper prey makes its way across the trap. If the insect touches just one hair, the trap will not spring shut; but a large enough bug will likely touch two hairs within about twenty seconds, and that signal springs the Venus flytrap into action. We can look at this system as analogous to short-term memory. First, the flytrap encodes the information (forms the memory) that something (it doesn’t know what) has touched one of its hairs. Then it stores this information for a number of seconds (retains the memory) and finally retrieves this information (recalls the memory) once a second hair is touched.

Based on the passage, a significant advantage of the Venus flytrap’s requirement for multiple triggers is that it

• A) enables the plant to identify the species of its prey.

• B) conserves the plant’s calcium reserves.

• C) safeguards the plant’s energy supply.

• D) prevents the plant from closing before capturing its prey

Wegner, the senior author of the study, believes the new findings show that the Internet has become part of a transactive memory source, a method by which our brains compartmentalize information. First hypothesized by Wegner in 1985, transactive 20 memory exists in many forms, as when a husband relies on his wife to remember a relative’s birthday. “[It is] this whole network of memory where you don’t have to remember everything in the world yourself,” he says. “You just have to remember who 25 knows it.” Now computers and technology as well are becoming virtual extensions of our memory.

In context, the reference to remembering a relative’s birthday mainly serves to

• A) show that people who are closely related tend to have shared memories.

• B) demonstrate how people initially developed external sources of memory.

• C) emphasize the effectiveness and accuracy of transactive memory sources.

• D) illustrate the concept of a transactive memory source using a familiar situation