Oxygen-Carbon Cycle worksheet - Free Printable

Explanation:
Let’s look at the oxygen-carbon cycle step by step.

1. First, we see the sun. The sun gives energy to plants. Plants use sunlight to make food. This process is called photosynthesis. During photosynthesis, plants take in carbon dioxide from the air. So, the arrow from the sun to the tree should be labeled: "Plants absorb carbon dioxide during photosynthesis."

2. Next, we see the tree. Plants make oxygen during photosynthesis and release it into the air. So, the arrow from the tree going up should be labeled: "Plants release oxygen during photosynthesis."

3. Now, look at the bison. Animals, like the bison, breathe in oxygen from the air. They use oxygen to break down food for energy. When they breathe, they release carbon dioxide. So, the arrow from the bison to the air should be labeled: "Animals breathe in oxygen."

4. Finally, the arrow from the air to the bison shows what the bison takes in. The bison breathes in oxygen. The arrow from the bison to the air shows what it breathes out. It breathes out carbon dioxide. So, the arrow from the bison to the air should be labeled: "Animals breathe out carbon dioxide."

Now, let’s match the sentences to the correct boxes:

- The box above the tree (with the arrow from the sun) goes to: "Plants absorb carbon dioxide during photosynthesis."
- The box to the right of the tree (with the arrow going up) goes to: "Plants release oxygen during photosynthesis."
- The box to the left of the bison (with the arrow from the air) goes to: "Animals breathe in oxygen."
- The box below the bison (with the arrow going to the air) goes to: "Animals breathe out carbon dioxide."

Final Answer:
- Top left box (from sun to tree): Plants absorb carbon dioxide during photosynthesis.
- Top right box (from tree to air): Plants release oxygen during photosynthesis.
- Bottom left box (from air to bison): Animals breathe in oxygen.
- Bottom right box (from bison to air): Animals breathe out carbon dioxide.