How living things move carbon

Grade 9 Science Worksheet - Building Confidence

Circle the best answer.

1. 1.

   Ari reads a carbon cycle diagram of a meadow. The arrow from the air to the grass has a blank label. Which process belongs on it?

   • Photosynthesis, which takes carbon dioxide in
   • No process, since the grass makes its own carbon
   • Cellular respiration, which takes carbon dioxide in
   • Decomposition, which takes carbon dioxide in
2. 2.

   Esme reads the arrow from the decomposers to the air. It carries carbon dioxide, and its label is blank. Which process belongs on it?

   • Dissolving, which moves carbon dioxide into the ocean
   • Photosynthesis, which returns carbon dioxide to the air
   • Decomposition, which returns carbon dioxide to the air
   • Destruction, which makes the carbon in remains vanish
3. 3.

   Jun reads a meadow diagram. Box W supplies the carbon dioxide that the grass takes in and receives what the grass gives back. Which store is box W?

   • The atmosphere
   • A rock layer
   • The soil
   • The ocean
4. 4.

   Kira reads the arrows between the air and box X. Carbon dioxide gas dissolves into box X and leaves it again. Which store is box X?

   • The soil
   • No store, since carbon dioxide cannot move into water
   • The ocean
   • A rock layer
5. 5.

   Flow diagram of the carbon cycle (model, not to scale), Earth as a whole. Luz reads a carbon store diagram. Box W holds most of Earth’s carbon. Which store is box W?

   • Rock layers
   • The atmosphere
   • The soil
   • Plants and algae
6. 6.

   Noah reads a glossary entry. Which meaning fits the term decomposer?

   • An organism, such as a fungus, that breaks down remains and wastes
   • An organism, such as grass, that makes sugar from carbon dioxide and light
   • An organism, such as a fungus, that destroys the carbon in remains
   • An organism, such as a grasshopper, that gets carbon from plant material
7. 7.

   Pia reads a glossary entry. Which meaning fits the term carbon cycle?

   • The path of carbon until decomposers destroy it for good
   • The flow of energy from the Sun through food to heat
   • The movement of carbon among air, water, rock and living things
   • The making of new carbon atoms by green plants and algae
8. 8.

   Ren sees that grass takes in carbon dioxide in light. At night the grass cells still use sugar for energy. Which gas do they give off?

   • Carbon dioxide, from cellular respiration
   • Carbon, as new atoms made from the sugar
   • Oxygen, from photosynthesis at night
   • No gas, since plants do not release carbon dioxide
9. 9.

   Tala follows carbon in a fallen leaf. Decomposers break the leaf down. In what form does much of its carbon return to the air?

   • As nothing, since decomposers destroy the carbon
   • As carbon dioxide gas
   • As sugar, made new by the decomposers
   • As oxygen gas, made from the leaf
10. 10.

    Zee reads two arrows between the air and the ocean surface. What do they show?

    • Carbon dioxide moves into the water and is destroyed there
    • Carbon dioxide moves into the water and out of it again
    • The ocean takes no part, since the arrows show wind
    • Carbon dioxide moves in one direction, from the water to the air