The green insectivorous plants trap insects, kill them and digest them to obtain mainly :

Options

A. glucose
B. starch
C. nitrogen
D. oxygen

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks what green insectivorous plants obtain by trapping, killing, and digesting insects.

2. **Identifying the Plant Type**: These plants, such as the pitcher plant, are known for their ability to trap insects. They are called insectivorous because they derive nutrients from insects.

3. **Photosynthesis**: Although these plants can perform photosynthesis due to the presence of chlorophyll, which allows them to convert sunlight into energy, they still require additional nutrients.

4. **Nutrient Deficiency**: Insectivorous plants often grow in nitrogen-deficient soils. This means that they cannot obtain enough nitrogen from the soil to support their growth.

5. **Obtaining Nutrients from Insects**: To compensate for the lack of nitrogen in their environment, these plants trap and digest insects. By doing this, they can absorb nitrogen, which is essential for their growth and development.

6. **Conclusion**: Therefore, the main nutrient that green insectivorous plants obtain from digesting insects is nitrogen.

**Final Answer**: The green insectivorous plants trap insects, kill them, and digest them to obtain mainly nitrogen.

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