Abstract to top Pollen is everywhere. It is in the air we breathe, the water we drink, in the food we eat, and in the soil we walk on. It is the pretty yellow, white, or blue powdery substance that is seen in flowers and can be so easily collected. Its abundance and ease of collection make it a useful substance for investigation in the high school science classroom.
Pollen grains contain the male gametes in sexually reproducing plants.
A pollen tube grows from the stigma, through the style, and into the ovary where it enters an ovule. The sperm nuclei then pass through the pollen tube into the ovary where fertilization takes place. The growth of the pollen tube in vivo cannot be seen since it takes place within the style. We present here several methods that promote the germination and pollen tube formation in vitro allowing students to see the process take place right before their eyes. It also provides excellent examples of cytoplasmic streaming.