Here's why:

* Stigma: The stigma is the topmost part of the pistil, the female reproductive organ of a flower. It's often sticky or covered in hairs to help capture pollen grains.

* Pollen: Pollen is the male gamete (sex cell) of a plant. When pollen lands on the stigma, it initiates the process of fertilization.

Let me know if you have any more questions!