Reading Comprehension

PT155 · S3 · P3 · Q19 Nanoscale Computer Chips

A free, expert breakdown of this official LSAT Reading Comprehension question.

  • Save & drill this skill build targeted practice sets from questions like this one

  • Video walkthroughs watch every question solved step by step

  • 81 official LSATs as questions, timed sections & full-length tests

This passage was adapted from an article published in 2000.

Topic

Belcher and Hu's research using peptides — short amino-acid chains — to build nanoscale electronic components.

Framework

Highlight Noteworthy. The author isn't arguing against anyone; the author is showcasing a promising approach to a coming problem in chip miniaturization.

Main Point

Conventional miniaturization is about to hit a hard physical limit, and Belcher and Hu's peptide-based approach is a promising route to building electronics below that limit. They have already identified hundreds of peptides that bind to specific semiconductor crystals and are now designing peptides that can act as molecular "glue" — exactly the kind of finesse needed for self-assembling nanocircuits.

P1: Why this work matters

The race to make computer chips smaller is approaching a wall (~2010): current transistors can't go below 25 nanometers. Living cells, however, routinely build complex structures at smaller scales. So researchers want to harness biological molecules. Most work focuses on DNA — Belcher and Hu are pursuing peptides instead.

P2: How they got there

The idea grew out of Belcher's discovery that a specific peptide directs calcium-carbonate crystallization in abalone shells. She and Hu reasoned that peptides able to direct crystal growth in semiconductor materials could be a tool for building nanoscale electronics. Since no known peptide had this property, they screened a billion random peptides against three semiconductor materials and isolated ones that bound to specific faces of specific crystals — then refined them via accelerated-evolution-style methods.

P3: Where things stand and what's next

To assemble a real toolkit, many more binding peptides are needed. They're making progress: hundreds of crystal-manipulating peptides across 20+ semiconductor materials, plus newly designed peptides that bind to two different crystals at once — molecular glue. That kind of nanoscale finesse is what self-assembling circuits will require.

19.

Which one of the following situations involving volatile oils is most analogous to the situation involving peptides that is presented in the passage?

  1. A group of researchers, whose

    Bad Match: abandons inquiry

    If "volatile oils" is playing the role of "peptides", then this is saying that Belcher was working on peptides and then received a grant to study something else altogether.

    2% picked this

  2. A group of researchers extracts

    Bad Match: powerful insecticide

    The idea of testing each volatile oil to determine whether it has properties that could make it useful to human applications would be similar to testing peptides to see whether they have properties (binding to semiconductor materials) that would make them useful to human computing applications. But this is saying during that phase, they discover that the oil can actually be used for something else. In the passage, as Belcher and Hu were testing peptides for use in computing, they didn't suddenly discover that one of the peptides was good for something else.

    11% picked this

  3. A group of researchers synthesizes

    Bad Match: when combined

    This is talking about making several volatile oils in the lab that are useful when combined. The peptides that Belcher and Hu found were responsive to semiconductor materials were responsive on their own. They didn't need to be combined to be useful. This answer also involves a further experiment and a completely different usage. Belcher and Hu didn't have any completely different usage. All their experimentation was aimed at designing nano-circuits.

    12% picked this

  4. A group of researchers observes

    Bad Match: used in medical applications

    This answer starts off like a good match for Belcher's abalone epiphany. We have researchers studying a natural object and discovering a funky property of a volatile oil. Then they launch a project (like Belcher and Hu did). But in Belcher and Hu's case, the project was to make and test new peptides to see if any could be used in human computing applications. In this answer choice, the project was to test existing volatile oils that were already being used in human applications.

    8% picked this

  5. Correct

    A group of researchers, noting

    Why this is right

    This answer starts off as a good match for Belcher's abalone epiphany. We have researchers studying a natural object and discovering a funky property of a volatile oil. That funky property makes us think of a potential human application. Next, we start trying to make/synthesize our own volatile oils (just like B&H started making their own peptides) and test them to see whether each one would work for our human purpose.

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

    67% picked this

Continue the review in LSAT Lab

Save this question, watch the video walkthrough, and drill similar questions in your LSAT Lab account.

LSAT Lab

Turn this review into a targeted study plan.

Save this question, drill more like it, watch the video walkthrough, and track your progress in your LSAT Lab account.

Start practicing free