Page 80 - Science Course 2 (Book 2)

Mo10-L1: Key Concept Check

Direction: On the line before each statement, write the letter of the correct answer.

1. Phosphorus does not exist in the
A. biosphere.
B. geosphere.
C. atmosphere.

2. Phosphates are formed when phosphorus reacts with
A. carbon.
B. oxygen.
C. nitrogen.

3. Plants absorb phosphorus from soil or
A. air.
B. water.
C. animals.

4. Phosphates in living things can return to soil during
A. respiration.
B. decomposition.
C. photosynthesis.

5. Phosphorus that is stored in organisms
A. never recycles.
B. recycles slowly.
C. recycles quickly.
6. Clearing trees in rain forests
A. disturbs the phosphorus cycle.
B. improves the phosphorus cycle.
C. does not impact the phosphorus cycle.

7. Excessive algal growth can occur when phosphorus levels in ponds
A. increase.
B. decrease.
C. do not change.

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