Apoptosis: Caspase Cascades and the Decision to Die · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

The cell that dismantles itself

Science · Organisms & Life Processes · ages 20-21
Name ______________________   Date ____________

  1. Why does a cell keep its death machinery ready but inactive?

    • To save energy during the cell cycle at rest
    • To divide faster whenever growth factors arrive
    • To activate the kill in seconds when ordered

  2. What happens to the contents of a cell undergoing apoptosis?

    • It spills its contents and inflames the tissue around it badly
    • It packs itself into neat parcels that neighbors swallow
    • It swells until it bursts randomly

  3. A broken death pathway can help grow a tumor without any extra division speed. True or false?

    Circle one:   True   False

  4. What role do mitochondria play in apoptosis?

    • It copies all of the DNA one last time before dying
    • It pumps in extra nutrients for the journey
    • It releases cytochrome c to build the apoptosome

  5. One caspase cuts one target and then stops. True or false?

    Circle one:   True   False

  6. How does the cell cycle connect to the death decision?

    • They speed the cycle past every single checkpoint without pausing at all
    • They halt for repairs, ordering death only if damage cannot be fixed
    • They delete all of the death machinery to protect every division

  7. A tissue overgrows at the normal division rate because division ran faster. True or false?

    Circle one:   True   False

  8. How do cancer cells exploit the death pathway?

    • Dodge apoptosis and pile up
    • Divide twice as fast as healthy cells do in every tissue
    • Repair every bit of DNA damage perfectly every single time
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Answer key

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

The cell that dismantles itself W1-mt_Pi6c9yoT7w-s1

  1. To activate the kill in seconds when ordered · Stocked sleeping procaspases switch on fast, since building them on demand would be too slow.
  2. It packs itself into neat parcels that neighbors swallow · Ordered dismantling keeps the contents wrapped, so neighbors stay unharmed.
  3. True · A broken death pathway can help grow a tumor by letting cells live that should have died.
  4. It releases cytochrome c to build the apoptosome · The organelle acts as the point of no return by launching the first caspase.
  5. False · Each level multiplies the kill across hundreds of targets.
  6. They halt for repairs, ordering death only if damage cannot be fixed · Division control and death control share the same inspectors by design.
  7. False · The surplus comes from deaths that never happened.
  8. Dodge apoptosis and pile up · Escaping programmed death removes one constraint on growth, letting survivors accumulate.
Worksheet · LightMySky