7th grade How carbon moves through living things and the air worksheet

How carbon moves through living things and the air

Grade 7 Science Worksheet

Circle the best answer.

1. 1.

   Which process takes carbon dioxide out of the air, Ari?

   • Burning fuels
   • Photosynthesis
   • Decay of fallen leaves
   • Respiration by animals
2. 2.

   A plant does photosynthesis in sunlight and respiration day and night. On a sunny day, what is true about its carbon dioxide, Esme?

   • It takes in more than it gives out
   • It does just respiration
   • It uses no carbon dioxide
   • It gives out more than it takes in
3. 3.

   In the diagram, carbon dioxide moves from the air into the sea. Which way does arrow X point, Jun?

   • From the air into the ocean
   • From the ocean into the air
   • From the ocean into the plants
   • From the fossil fuels into the sea
4. 4.

   NASA says the ocean now takes in more carbon dioxide than it gives off. Which way does the bigger arrow point, Kira?

   • Neither: they are the same size
   • From the ocean into the air
   • From the ocean into the rock
   • From the air into the ocean
5. 5.

   Follow the arrows in the diagram. Where can carbon from burned fuel end up, Luz?

   • In the Sun
   • In the ocean first, then the fuel
   • In the air, and some in the ocean
   • Back in the fuel
6. 6.

   In northern winter, carbon dioxide in the air climbs. Which explanation fits, Noah?

   • Snow makes carbon dioxide
   • The ocean freezes over
   • Plants take in much more carbon dioxide
   • Little growth, while decay keeps going
7. 7.

   The yearly up-and-down in carbon dioxide follows the seasons. Which process mainly drives the summer dip, Pia?

   • Respiration by animals
   • Photosynthesis
   • Decay
   • Dissolving into the ocean
8. 8.

   A maple tree grows heavier each year. What happens to the carbon in the air when it does, Ren?

   • The tree makes brand-new carbon
   • Some moves out of the air into the tree
   • The air gains carbon
   • The tree pulls its carbon up from the soil
9. 9.

   After decomposers break down a fallen log, where is most of its carbon, Tala?

   • Back in the air as carbon dioxide
   • Turned into energy and gone
   • Inside the fossil fuels
   • Gone: decomposers use it up
10. 10.

    In a food web, energy flows on and leaves as heat. What happens to the carbon atoms, Zee?

    • They leave as heat, like energy
    • They are used up at each step
    • They are recycled again and again
    • They stay locked in the plants for good