Which of the following is not correct with respect to a part of the flower and its function ?

Options

A. Sepals are green leaf - like structures which protect the flower after opening.
B. Petals are usually brightly coloured to attracts insects for pollination .
C. Staminodes produce pollen grains.
D. Stigma is the tip of carpel and is the receptive surface for pollen grains.

Answer

To determine which statement is not correct regarding a part of the flower and its function, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Analyze the first option:**
- **Statement:** "Sepals are green leaf-like structures which protect the flower after opening."
- **Explanation:** Sepals are indeed green, leaf-like structures that protect the flower bud before it opens. After the flower opens, they may still provide some protection but are primarily there during the bud stage.
- **Conclusion:** This statement is correct.

2. **Analyze the second option:**
- **Statement:** "Petals are usually brightly colored to attract insects for pollination."
- **Explanation:** Petals are often brightly colored and serve to attract pollinators such as insects. This is a well-known function of petals.
- **Conclusion:** This statement is correct.

3. **Analyze the third option:**
- **Statement:** "Staminodes produce pollen grains."
- **Explanation:** Staminodes are indeed sterile or rudimentary stamens that do not produce pollen grains. Therefore, this statement is incorrect.
- **Conclusion:** This statement is not correct.

4. **Analyze the fourth option:**
- **Statement:** "Stigma is the tip of the carpel and is the receptive surface for pollen grains."
- **Explanation:** The stigma is the part of the carpel that receives pollen during fertilization. It is sticky and designed to capture pollen grains effectively.
- **Conclusion:** This statement is correct.

### Final Answer:
The statement that is not correct is: **"Staminodes produce pollen grains."**