Energy in Ecosystems — Answer Key
Part A: Fill in the Blank
Write the missing word or number on each line.
1. Matter in an ecosystem is constantly being recycled.
Unlike energy, matter cycles within an ecosystem and is not lost.
2. Plants take in carbon dioxide from the air during photosynthesis.
Carbon cycles between living things and the atmosphere through photosynthesis and breathing.
3. Animals breathe out carbon dioxide that plants then take in.
This shows how carbon moves between producers and consumers.
4. Plants release the gas oxygen during photosynthesis.
Producers make oxygen as they make food, supporting consumers in the ecosystem.
5. Water moves through ecosystems in the water cycle.
The water cycle carries water through living and nonliving parts of every ecosystem.
6. Nutrients return to the soil when decomposers break down dead matter.
Decomposed matter releases nutrients that producers reuse to grow.
7. Plants pull water and nutrients from the soil through their roots.
Roots take in materials needed for photosynthesis and growth.
8. All the living and nonliving parts of an area form an ecosystem.
An ecosystem includes producers, consumers, decomposers, and nonliving parts like soil.
9. Energy in an ecosystem flows in one direction, but matter cycles.
Grade 5 students learn that energy flows one way while matter cycles repeatedly.
Part B: Matching
Match each item on the left to the correct answer on the right.
1. Match each item to its correct answer.
Carbon dioxide
→ Gas plants take in for photosynthesis
Gas plants take in for photosynthesis
Oxygen
→ Gas plants release that animals breathe
Gas plants release that animals breathe
Water cycle
→ Movement of water through Earth and the air
Movement of water through Earth and the air
Ecosystem
→ All living and nonliving parts of an area
All living and nonliving parts of an area
Understanding these cycles helps Grade 5 students see how matter moves through ecosystems.