In ecosystems ________and __________ are conserved.

Explanation

**Step-by-Step Solution:**

1. **Understanding Ecosystems**: Begin by recognizing that ecosystems are complex networks where living organisms interact with each other and their physical environment.

2. **Identify What is Conserved**: In ecosystems, two fundamental concepts are important: matter and energy. These are the two key elements that are conserved.

3. **Conservation of Matter**: Matter in an ecosystem refers to the physical substances that make up organisms and their environment. Matter is conserved because it cycles through the ecosystem. For example, when plants absorb nutrients from the soil, these nutrients are used to create new plant matter. When animals eat plants, the matter is transferred to them, and when they die, their matter is decomposed and returned to the soil.

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