Reading Comprehension · Science
PrepTest 155 · Section 3 · Passage 3
Questions 16–22
Before you start
Open PrepTest 155, Section 3 in your official copy from LSAC and read the passage for Questions 16–22, using the structure guide below. The passage is not reprinted here.
Structure guide
- P1: sets up a looming limit on current methods, suggests a natural route around it, notes the popular approach, and introduces researchers trying a different one
- P2: traces the project to an earlier finding, names an obstacle, and describes a broad screening experiment and how the winners were improved
- P3: reports a researcher's view of what is still needed, the progress so far, a new direction, and closes on what the final goal will require
Step 2 · The kid passage
The Tiny Sprinkle Race
At Aunt Rosa's bakery, every baker races to make cake decorations smaller, because tiny designs sell faster. But there is a snag. A piping bag cannot squeeze a line thinner than a thread, so the race will soon stall, and the bakers hate that thought. Nature, though, builds teeny patterns all the time: frost draws lacy ferns on windows. Maybe natural helpers could build tiny decorations. Most kids in bake club are trying salt grains as their helper. Priya and Nadia are testing something else: spice blends.
The idea began with Priya's old rock-candy project. She found that one pinch of cinnamon makes sugar set into star shapes, and only star shapes. The girls thought: a blend that steers colored frosting would be a tool for tiny designs. But no known blend did that. So they mixed a thousand random blends and tried each one on vanilla, chocolate, and lemon frosting. A handful stuck to just one frosting, and even to just one side of a sprinkle. Then they mixed brand-new blends from those winners.
Nadia says a full decorating kit would need many more blends that stick to frosting. They are getting there: they have tried twenty more frostings, and their pile of useful blends has grown to hundreds. Now they are making blends that grab two frostings at once, like a dab of glue. Nadia grins: "Decorations that build themselves will need exactly that kind of skill."
Step 4 · The courtroom tale
The Case of the Five Hundred Ribbons
A town council sued a kite maker for spending grant money on five hundred random tail ribbons. Mr. Whitfield snapped his suspenders. "Your Honor, the old tails cannot hold a kite steady above a certain height. Everyone agrees on that wall. My client tried a new helper instead. Out of five hundred ribbons, three kept a kite steady, and only on windy days. From those three she made twelve better ones." The council lawyer frowned. "But she has no finished kite." "True," said Mr. Whitfield. "She says she needs many more ribbons, and she is getting them. That is how a big goal grows: first the problem, then a few lucky winners, then a bigger toolbox." The judge nodded. "Grant money well spent. Case dismissed."