The importance of green plants on the ecosystem is :

Options

A. they increase the fertility of the soil by decomposing
B. they are autotrophs
C. act as tertiary consumers.
D. act as secondary consumers.

Answer

### Step-by-Step Solution:

1. **Definition of Green Plants**: Green plants are organisms that can produce their own food through a process called photosynthesis. They contain chlorophyll, which gives them their green color.

2. **Photosynthesis Process**: During photosynthesis, green plants use sunlight, carbon dioxide (CO2), and water (H2O) to produce glucose (a type of sugar) and oxygen (O2). The chemical equation for photosynthesis can be summarized as:
\[ \text{6 CO}_2 + \text{6 H}_2\text{O} + \text{light energy} \rightarrow \text{C}_6\text{H}_{12}\text{O}_6 + \text{6 O}_2 \]

3. **Role as Producers**: Because they can create their own food, green plants are classified as autotrophs. This means they are the primary producers in an ecosystem, forming the base of the food chain.

4. **Providing Food**: Green plants serve as a crucial food source for heterotrophic organisms (consumers), including animals and humans. These organisms depend on plants for their nutritional needs.

5. **Soil Fertility**: Green plants contribute to soil fertility through the decomposition of organic matter. When plants die or shed leaves, they decompose and enrich the soil with nutrients.

6. **Conclusion**: The importance of green plants in the ecosystem can be summarized as:
- They are autotrophs (producers) that provide food for all heterotrophic organisms.
- They enhance soil fertility through decomposition.

### Final Answer:
The importance of green plants in the ecosystem is that they are autotrophs (producers) that provide food for heterotrophic organisms and contribute to soil fertility.

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