whorl of small green structures present around sunflower is

Options

A. epicalyx
B. calyx
C. leaves
D. involucre.

Answer

To answer the question regarding the whorl of small green structures present around a sunflower, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the small green structures surrounding the sunflower. We need to identify the correct term for these structures from the given options.

2. **Analyzing the Options**:
- **Option 1: Apicalyx**: This is an additional whorl of structures similar to the calyx, found in some flowers like hibiscus. It is not present in sunflowers, so this option is incorrect.
- **Option 2: Calyx**: The calyx is a ring of small green leaves that protect the flower in its bud stage. However, in sunflowers, the structures surrounding the flower are not classified as the calyx. Thus, this option is also incorrect.
- **Option 3: Leaves**: While leaves are indeed present on the stem of the sunflower, they do not refer to the structures surrounding the flower. Therefore, this option is incorrect as well.
- **Option 4: Involucre**: The involucre is a whorl of bracts (modified leaves) that surrounds the flower head in sunflowers. This is the correct term for the small green structures surrounding the sunflower.

3. **Conclusion**: After analyzing all the options, the correct answer is **Involucre**.

### Final Answer:
The whorl of small green structures present around the sunflower is called the **Involucre**.

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