Students will be able to:
Plants usually produce a small number of ovules, but millions of pollen grains.
To produce a seed, pollen must be moved from an anther to the stigma of the same type of flower. This is process is called pollination.
Depending on the plant species, the pollen may have to be moved a few millimetres or many metres, either by animals such as insects, or the wind.
Once on the stigma the pollen grain produces a pollen tube that grows down inside the pistil to reach an ovule and achieve fertilisation. The ovule then grows into a seed.
Structure | Insect pollinated | Wind pollinated |
| Flowers | Usually conspicuous* and often large | Inconspicuous*, often dull and small |
| Petals | Often large and brightly coloured | Dull and small |
| Pollen | Heavy and sometimes sticky | Light |
| Stamen | Near entrance to flower | Positioned high on the plants and dangle outside flower |
| Stigma | Sticky and near entrance to flower | Large and feathery |
| Nectar | Makes nectar | None |
| Scent | Usually scented* | Unscented* |
* Meanings of words in table
Conspicuous: easily seen.
Inconspicuous: not easily seen.
Scented: smells (usually nice).
Unscented: no smell.
Flowers pollinated by animals | Flowers pollinated by wind |
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Resources |
Flower dissection activity sheet
Picture credits: Thumbnail diagram and Parts of Flower diagram (Pixy.org).
