Pollination

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Pollination is part of how flowering plants make seeds. Pollination involves pollen from the male parts of a flower getting to the female parts of a flower (usually a different flower). Each pollen grain has half of the DNA (genetic information) that is needed to make a new plant. During fertilization this combines with the DNA that is in the egg of the female part and a new seed is started.

[change] Ways of pollinating

Pollen has to get from one flower to another. There are two main ways that this can happen: by living things like bees, or by non-living things like wind or water.

For example - Tomatoes and bees

Tomato plants need bees to move the pollen from the male parts of one flower (anthers), to the female parts of another flower (stigma). The bee moves between flowers not because it is feeling helpful, but because it wants to collect the sweet nectar that the flowers have on offer. The bees take the nectar home to their hive to make honey and the tomato plants get to reproduce (make new tomato plants).

Because the tomato flowers have evolved (changed over time) to attract bees, they have spread-out petals and are white to human eyes (but much prettier to bee eyes). The pollen is big and will get stuck to the bee and taken to the next flower, where it can get rubbed off on the sticky female stigma and grow down to fertilize an egg and make a seed.

For example - Maize and the breeze

Maize (just called corn in some parts of the world, like New Zealand) is pollinated by wind. The male anthers let go of their pollen and it blows over to a nearby female flower on another corn plant. Most of the flowers are either male OR female on a corn plant, rather than both sexes in one flower.

Because the maize flowers have evolved (changed over time) to use wind for pollination they are mostly just greenish in color - they don't need pretty petals. The pollen is light so it can blow around, and the ends of the female parts (stigma) are fluffy to catch all the tiny pollen grains.

80% of plants are pollinated use biotic (living things like insects) pollination, and only 20% use abiotic (non-living things) pollination. Of these abiotic pollinations, 98% is done by wind and just 2% by water.