Earth is a closed system as far as materials are concerned.

Answer

**Step-by-Step Solution:**

1. **Understanding Closed Systems:**
- A closed system is defined as a system where energy can enter or leave, but matter cannot. In this context, Earth is considered a closed system for materials.

2. **Energy Exchange:**
- While Earth retains its materials, it can receive energy from external sources, primarily from the Sun. This energy can enter the system, which is a characteristic of an open system regarding energy.

3. **Atmospheric Insulation:**
- The atmosphere acts as an insulating layer for Earth. This insulation helps to keep the materials (like gases, water, and minerals) within the Earth system while allowing energy (like sunlight) to penetrate.

4. **Conclusion:**
- Therefore, since Earth does not lose materials to space but can receive energy, we conclude that Earth is a closed system for materials and an open system for energy. This statement is TRUE.

**Final Answer:**
Earth is a closed system as far as materials are concerned, but it is an open system for energy.

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