Nitrogen Stable Isotopes Are Useful Tools for the Study of Food

question 7

Multiple Choice

Nitrogen stable isotopes are useful tools for the study of food web structure because isotope ratios

• A) change in predictable ways across trophic levels.
• B) often vary among alternative food sources for a consumer.
• C) for a predator exactly match the isotope ratio in its prey.
• D) both change in predictable ways across trophic levels and often vary among alternative food sources for a consumer.

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