Parachute mechanism of fruit and seed dispersal is common in compositae is due to the structure called :-

Options

A. bract
B. pappus
C. coma
D. barbs

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the structure responsible for the parachute mechanism of fruit and seed dispersal in the Compositae family (now known as Asteraceae).

2. **Identifying the Structure**: The structure that facilitates this type of dispersal is known as the "Pappus."

3. **Defining Pappus**: The Pappus is a modified structure derived from sepals. It plays a crucial role in aiding the dispersal of seeds and fruits by utilizing wind.

4. **Characteristics of Pappus**: The Pappus can vary in its form. It can be composed of:
- Scales
- Bristles
- Tufts of hair-like structures

5. **Function of Pappus**: The most common form of Pappus is tufts of hair-like bristles. These structures allow seeds to be carried away by the wind, effectively facilitating the parachute mechanism of dispersal.

6. **Conclusion**: Therefore, the answer to the question is that the parachute mechanism of fruit and seed dispersal in Compositae is due to the structure called the Pappus.

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