Pollen is the delivery package for plant sperm, or the plant’s male reproductive cell. It moves from the male plant to the female plant through a variety of delivery mechanisms.
You know it’s springtime again when you step outside and your sinuses start giving you a headache. Ask any doctor, and he or she will give you a lecture about pollen count, and how important it is to take antihistamines so you can go outside again. What good is pollen, anyway? Why do we have to put up with all this sneezing each year? Well, it turns out pollen is one of the most important things when it comes to plants, and, ultimately, the food we eat.
So, what is pollen?
Pollen is the male reproductive cell of a plant.
Each pollen grain contains a sperm cell, which needs to fertilize an egg cell in order to produce seeds. Pollen is produced by the male portion of a flower, those sometimes showy, sometimes smelly blooms we associate with spring.You see, plants, just like animals and humans, have males and females. Sometimes a single flower with only have male or female parts. Sometimes a single flower will have both male and female parts – they are hermaphrodites.
Either way, the male parts produce sperm, while the female parts produce eggs, just like in humans. The delivery system is a little bit different, though. You wouldn’t see a male flower trying to get a date at a bar! No, instead, the sperm is packaged in specialized grains that use a variety of ways to get to the female portion of the plant.
Where is pollen produced?
Flowers aren’t just for show. They’re actually very sophisticated reproductive organs. The petals of a flower attract pollinators, those things that move pollen from the plant to the flower. Inside the flower are a stamen and a carpel. The stamen produces pollen, while a carpel contains an egg.
How does pollen get to an egg?
Ah, this is where plants get really clever. You see, over millions of years, different plants have devised different ways to move their sperm, in the form of pollen, to the egg within a carpel. Some plants have big showy flowers and nice smells.
These plants attract pollinators – like bees, insects and some birds – to pick up pollen and move it along. Other plants drop pollen into the water and let it float downstream. Still others take advantage of the wind.
Have you ever walked outside and seen your car covered in light yellow dust? Yep, that’s pollen, taking a ride on the wind and hoping to run into a female flower.Once pollen reaches an egg, a seed of a new plant can form. This often goes hand in hand with fruit, and other parts of the plant that we find tasty. So, while pollen can be annoying if we accidentally breathe it in during its mating flight, once it reaches its destination, we get to have a wonderful meal.
Pollen is a microscopic grain that contains plant sperm.
Plants use pollen to deliver the sperm to the egg. Pollen moves from the stamen of a plant to the carpel of a plant through pollinators, wind, or water.
When students are done here, they should have the confidence to:
- Define pollen
- Describe how pollen is created and how it reaches eggs
- Explain the effects of pollen on some people’s respiratory systems