Osmosis in Plant and Animal Cells · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Where water sneaks across

Science · Organisms & Life Processes · ages 14-15
Name ______________________   Date ____________

  1. Why does a plant cell survive in pure water while a red blood cell bursts?

    • Water cannot enter plant cells
    • The plant cell has a stiff wall
    • The plant cell has no membrane

  2. Pure water sits on one side of a membrane and strong sugar solution on the other. Which way does the water move?

    • Toward the sugar solution
    • Toward the pure water
    • Both ways equally

  3. A turgid plant cell is full of water and held firm by its wall.

    Circle one:   True   False

  4. Soil dries out after weeks without rain. Why does the plant wilt?

    • The cell walls dissolve
    • Water floods into the roots
    • Water leaves the root cells for the concentrated soil

  5. A potato piece weighs 5.0 g, then 5.8 g after soaking in pure water. What is the percentage change?

    • 16 percent gain
    • 0.8 percent gain
    • 8 percent gain

  6. A drip meant to match blood cells bursts the red cells instead. What was the drip?

    • Exactly matched to the cells
    • More dilute than the cells
    • More concentrated than the cells

  7. Two potato pieces gain 4 percent and lose 12 percent in different solutions. Which solution was more concentrated?

    • The one where the piece gained mass
    • Both were equally concentrated
    • The one where the piece lost mass

  8. A plasmolysed cell has its membrane pressed harder against the wall than a turgid cell.

    Circle one:   True   False

LightMySky · lightmysky.comW1-mt_XciCLO69xG-s1

Answer key

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

Where water sneaks across W1-mt_XciCLO69xG-s1

  1. The plant cell has a stiff wall · The stiff wall holds the swelling plant cell firm, while the red cell has no wall.
  2. Toward the sugar solution · Water moves to the more concentrated side, which is the sugar solution.
  3. True · Turgid means swollen with water, with the wall holding firm.
  4. Water leaves the root cells for the concentrated soil · Dry soil water is more concentrated than the cells, so water leaves the roots.
  5. 16 percent gain · The gain is 0.8 g, and 0.8 divided by 5.0 times 100 is 16 percent.
  6. More dilute than the cells · Water rushed into the cells and burst them, so the drip was more dilute.
  7. The one where the piece lost mass · Losing mass means water left the potato for a more concentrated solution.
  8. False · Plasmolysed means the membrane has pulled away from the wall as water left.
Worksheet · LightMySky