Diffusion across a cell membrane

Grade 7 Science Worksheet - Building Confidence

Circle the best answer.

1. Read this first

   Use this

   Cell arrow diagram (model data, not to scale). No arrows are drawn yet.

2. 1.

   Which side of the membrane has the higher concentration of carbon dioxide, Bo?

   • The two sides are even
   • Inside the cell
   • Outside the cell
   • Neither side has any
3. 2.

   Which side of the membrane has the higher concentration of oxygen now, Esme?

   • Inside the cell
   • The membrane holds the most
   • Neither: the sides are even
   • Outside the cell
4. 3.

   Which way will oxygen move across the membrane, Jun?

   • It won't cross the membrane
   • Into the membrane, where it stays
   • Into the cell
   • Out of the cell
5. 4.

   Which way will carbon dioxide move across the membrane, Kira?

   • Into the cell
   • It stays where it is
   • Out of the cell
   • Into the nucleus
6. 5.

   Milo reads the word diffusion in a science book. What does it mean?

   • Particles gathering where they are already crowded
   • Particles turning into new ones
   • Particles being pumped by the cell
   • Particles spreading from more crowded to less crowded
7. 6.

   Noah reads that particles move down their concentration gradient. Which way is that?

   • From the top of the cell to the bottom
   • From lower to higher concentration
   • Toward the membrane
   • From higher to lower concentration
8. 7.

   A cell membrane works a bit like a door with rules. What is its job, Pia?

   • It makes the cell's food
   • It blocks oxygen from entering
   • It controls what goes in and out
   • It holds the cell's DNA
9. 8.

   Does a cell spend energy to move oxygen in by diffusion, Ren?

   • Yes: the cell pumps it in
   • No: diffusion needs no energy from the cell
   • No: oxygen stays outside
   • Yes: the membrane pulls it in
10. 9.

    Why do particles spread out across a membrane on their own, Tala?

    • Empty space pulls them
    • They keep moving at random
    • Gravity drops them through
    • The cell pushes them along
11. 10.

    Diffusion is a kind of passive transport. What does passive mean here, Zee?

    • The cell spends energy on it
    • It needs no energy from the cell
    • It moves particles from fewer to more
    • It happens just in plants