Answer:
They enable protein production.
Explanation:
Because there always needs to be something that starts it off. Eg: If there was no grass, there would be no animals.
Answer: A.) The nitrogen cycle recycles nitrogen through an ecosystem, making it available to all organisms.
Explanation: Nitrogen is an essential nutrient for plants and a significant component of proteins, which all animals need to grow, reproduce and survive. The nitrogen cycle converts nitrogen into compounds that plants and animals can use.
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