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?

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

   Bo reads the arrow from the grass back to the air. It carries carbon dioxide, but its label is blank. Which process belongs on it?

   • Cellular respiration, which gives carbon dioxide back
   • No process, since plants do not release carbon dioxide
   • Photosynthesis, which gives carbon dioxide back
   • Decomposition, which gives carbon dioxide back
3. 3.

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

   • Photosynthesis, which returns carbon dioxide to the air
   • Dissolving, which moves carbon dioxide into the ocean
   • Destruction, which makes the carbon in remains vanish
   • Decomposition, which returns carbon dioxide to the air
4. 4.

   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 soil
   • A rock layer
   • The ocean
   • The atmosphere
5. 5.

   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
   • The ocean
   • A rock layer
   • No store, since carbon dioxide cannot move into water
6. 6.

   Milo reads a glossary entry. Which meaning fits the term carbon reservoir?

   • A store that holds carbon for a time, such as the air or the ocean
   • A process that takes carbon dioxide from the air into a leaf
   • A kind of rock that has no way to give its carbon back
   • An organism, such as a fungus, that breaks down old remains
7. 7.

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

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

   • Oxygen, from photosynthesis at night
   • No gas, since plants do not release carbon dioxide
   • Carbon, as new atoms made from the sugar
   • Carbon dioxide, from cellular respiration
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 oxygen gas, made from the leaf
   • As carbon dioxide gas
   • As sugar, made new by the decomposers
   • As nothing, since decomposers destroy the carbon
10. 10.

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

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