CRISPR: A Bacterial Defence Turned into a Tool · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

A filing system turned editor

Science · Microbiology · ages 20-22
Name ______________________   Date ____________

  1. What decides where the nuclease cuts?

    • The cell temperature
    • The time of day
    • The guide RNA sequence

  2. What sits in the CRISPR array as spacers?

    • Fragments of past invaders
    • Antibiotic molecules
    • Pieces of the cell wall

  3. Supplying our own guide redirects bacterial defence into an editing tool for a chosen site.

    Circle one:   True   False

  4. A break is patched quickly with no template. What edit results?

    • A designed insertion
    • Disruption of the site
    • No change at all

  5. Why does the nuclease spare the stored array itself?

    • The array hides in another cell
    • Its fragments lack the extra signal needed beside a true target
    • Guides never enter the cell

  6. A break is repaired against a supplied template. What edit results?

    • A designed sequence installed at the site
    • Random scrambling only
    • The guide is destroyed

  7. Retargeting CRISPR to a new site requires building a whole new nuclease protein.

    Circle one:   True   False

  8. A guide has a close lookalike elsewhere. What must the designer do?

    • Ignore it completely
    • Add more unrelated guides
    • Check the lookalike for off target cuts
LightMySky · lightmysky.comW1-mt_0joPWRvOLw-s1

Answer key

For grown-ups. Fold this page away before handing over the rest.

A filing system turned editor W1-mt_0joPWRvOLw-s1

  1. The guide RNA sequence · The guide pairs with its match and leads the cutter there.
  2. Fragments of past invaders · Surviving cells file invader fragments between repeats.
  3. True · Swapping the address label retargets the same machinery.
  4. Disruption of the site · Quick patching breaks the address rather than writing a plan.
  5. Its fragments lack the extra signal needed beside a true target · Without that neighbor signal the cutter stands down.
  6. A designed sequence installed at the site · Templated repair writes the provided plan into place.
  7. False · Only a new guide RNA is needed, which beats older tools.
  8. Check the lookalike for off target cuts · Near matches risk edits at the wrong address.
Worksheet · LightMySky