Question

carbon cycle
sunlight
co₂ cycle
factory emissions
photosynthesis
plant respiration
animal respiration
organic carbon
root respiration
decay organisms
dead organisms and waste products
fossil fuels

1. in the carbon cycle, the role of plants is to

○ a. break down dead organisms into usable matter.
○ b. remove carbon dioxide from the atmosphere.
○ c. convert nitrogen from the soil into carbon dioxide.
○ d. release carbon dioxide into the atmosphere.
□ mark for review (will be highlighted on the review page)

Explanation:

• Option A: Decomposers (like fungi/bacteria) break down dead organisms, not plants. Eliminate A.
• Option B: Plants perform photosynthesis, which uses \( \text{CO}_2 \) from the atmosphere to make glucose. This removes \( \text{CO}_2 \) from the air. This matches the carbon cycle role of plants.
• Option C: Plants do not convert nitrogen to \( \text{CO}_2 \); nitrogen and carbon cycles are distinct. Eliminate C.
• Option D: While plants respire (releasing \( \text{CO}_2 \)), their primary role in the carbon cycle is photosynthesis (removing \( \text{CO}_2 \)), not just releasing it. So B is more accurate.

Answer:

B. remove carbon dioxide from the atmosphere.