Pyramid of number is inverted in case of

Options

A. Pond ecosystem
B. Desert ecosystem
C. Grass land ecosystem
D. Forest ecosystem

Answer

**Step-by-Step Solution:**

1. **Understanding the Pyramid of Numbers**: The pyramid of numbers represents the number of organisms at each trophic level in an ecosystem. Typically, it is upright, with a large number of producers at the base and fewer consumers at higher levels.

2. **Characteristics of an Upright Pyramid**: In an upright pyramid, the base (producers) has the highest number of organisms. As you move up the pyramid to primary, secondary, and tertiary consumers, the number of organisms decreases. This reflects the energy transfer in an ecosystem, where energy diminishes at each trophic level.

3. **Inverted Pyramid of Numbers**: An inverted pyramid occurs when there are fewer producers at the base compared to the number of consumers at higher trophic levels. This is atypical and can happen in certain ecosystems.

4. **Examples of Inverted Pyramids**:
- In a desert ecosystem, there are very few producers (like plants) due to harsh conditions, but there can be a large number of consumers (like herbivores and carnivores) that rely on the limited producers.
- This leads to an inverted pyramid where the number of consumers exceeds the number of producers.

5. **Analyzing the Options**:
- **Pond Ecosystem**: Typically has a high number of phytoplankton (producers), making it an upright pyramid.
- **Desert Ecosystem**: Has fewer producers and a higher number of consumers, making it an inverted pyramid.
- Other ecosystems (not mentioned in detail) may also have upright pyramids.

6. **Conclusion**: The pyramid of numbers is inverted in the case of the desert ecosystem due to the low number of producers compared to the high number of consumers.

**Final Answer**: The pyramid of number is inverted in the case of the desert ecosystem.

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