Choose the correct answer :
Pyramid of biomass in a pond ecosystem is :

Options

A. Inverted
B. Always upright
C. Sometimes upright
D. Upright and sometimes inverted

Answer

To determine the correct answer regarding the pyramid of biomass in a pond ecosystem, we need to analyze the structure of the ecosystem and how biomass is distributed among different trophic levels.

### Step-by-Step Solution:

1. **Understanding the Pyramid of Biomass**:
The pyramid of biomass represents the total mass of living matter at each trophic level in an ecosystem. It typically shows the relationship between producers, consumers, and decomposers.

2. **Identify the Trophic Levels in a Pond Ecosystem**:
- **Producers**: In a pond ecosystem, the primary producers are aquatic plants and phytoplankton. They are at the base of the pyramid.
- **Primary Consumers**: These are herbivores like zooplankton that feed on the producers.
- **Secondary Consumers**: These include small fish and other organisms that feed on the primary consumers.
- **Tertiary Consumers**: Larger fish and predators like turtles and sharks that feed on the smaller fish.

3. **Analyzing Biomass Distribution**:
In a typical pond ecosystem, the biomass of the producers (aquatic plants) is usually greater than that of the primary consumers (zooplankton). However, as we move up the trophic levels, the biomass tends to decrease. This is because higher trophic levels have fewer individuals, and their combined biomass is often less than that of the lower levels.

4. **Conclusion**:
In a pond ecosystem, the pyramid of biomass is often **inverted**. This means that the biomass of the primary consumers (zooplankton) can exceed that of the primary producers (aquatic plants) due to their high numbers, despite individual weights being lower. Therefore, the correct answer is that the pyramid of biomass in a pond ecosystem is **inverted**.

### Final Answer:
The pyramid of biomass in a pond ecosystem is **inverted**.

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