Large ecosystems are called-

Options

A. Biomes
B. Ecotone
C. Ecads
D. Biogenesis

Answer

**Step-by-Step Solution:**

1. **Understanding Ecosystems**: Ecosystems can vary in size and complexity. They can be small, like a pond, or large, like forests or deserts.

2. **Defining Large Ecosystems**: Large ecosystems are typically referred to as "biomes." A biome is characterized by specific climate conditions, vegetation types, and wildlife.

3. **Examples of Biomes**: Common examples of biomes include:
- Tropical biome
- Tundra biome
- Taiga biome
- Grassland biome

4. **Characteristics of Biomes**: Biomes are defined as large communities of vegetation and wildlife that are adapted to specific climatic conditions.

5. **Conclusion**: Therefore, the correct answer to the question "Large ecosystems are called" is **biomes**.

6. **Review of Other Options**:
- **Ecotone**: This refers to a transition area between two biological communities, not a large ecosystem.
- **Ecards**: This term refers to organisms modified by their environment, which is not relevant to the definition of large ecosystems.
- **Biogenesis**: This term relates to the origin of life and is not related to ecosystems.

**Final Answer**: Large ecosystems are called **biomes**.

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