Pollinia are sac like structures

Options

A. Which secerete yellow substance
B. Which are found in megasporangia
C. In which anther lobes are present
D. In which pollen grains are present in mass

Answer

**Step-by-Step Solution:**

1. **Definition of Pollinia**: Pollinia are specialized structures that consist of a coherent mass of pollen grains. They are typically sac-like in shape and are involved in the process of pollination.

2. **Composition**: Each pollinium contains multiple pollen grains that are tightly packed together. The pollen grains are produced in the anther of a flower.

3. **Structure**: A typical pollinium consists of a disc-shaped structure and two wing-like extensions. The disc is the main body of the pollinium, while the wings help in the dispersal of the entire structure during pollination.

4. **Occurrence**: Pollinia are primarily found in certain plant families, notably orchids and milkweeds. These plants have evolved this structure to facilitate efficient pollination.

5. **Mechanism of Pollination**: During wind pollination or through the activity of pollinators, the entire pollinium can be transferred to the stigma of a compatible flower. Once it reaches a suitable stigma, the pollen grains can germinate and fertilization can occur.

6. **Function**: The main function of pollinia is to ensure the successful transfer of pollen from one flower to another, increasing the chances of fertilization and seed production.