In which of the following Pollinia are formed ?

Options

A. Zostera
B. Mirabilis
C. Vallisneria
D. Calotropis

Answer

**Step-by-Step Solution:**

1. **Understanding Pollinia**: Pollinia are defined as structures that consist of a cluster of pollen grains. They are formed by a single anther and are typically winged structures that facilitate wind pollination.

2. **Structure of Pollinia**: The structure of pollinia includes a stalk-like part, wings that contain the masses of pollen grains, and a disc. The wings are referred to as polyneum, and the entire structure is known as a pollinium.

3. **Function of Pollinia**: Pollinia are adapted for wind pollination, meaning that they can travel as a whole structure to compatible stigmas for fertilization.

4. **Identifying the Correct Option**: Among the given options: Zostera, Milabilis, Velisneria, and Callitropis, we need to identify which one forms pollinia.

5. **Analyzing the Options**:
- **Zostera**: This is a seagrass and does not produce pollinia.
- **Milabilis**: This is not a well-known plant associated with pollinia.
- **Velisneria**: This is an aquatic plant and does not produce pollinia.
- **Callitropis**: This plant belongs to the family Apocynaceae and is known to produce pollinia.

6. **Conclusion**: The correct answer is **Callitropis**, as it is the only option among the given choices that forms pollinia.

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