Flower structure and pollination
In a nutshell
Flowers have both male and female reproductive organs. They pollinate by getting pollen from the male reproductive organ to the female reproductive organ. As flowers cannot move, their pollination is aided by insects and the wind.
Flower structure
The flower has many different parts that are important for its growth and the growth of new plants.
| Part | Description |
1. | Stamen | The stamen is the male reproductive part of the flower. It consists of the anther and the filament. |
1. A | Anther | The anther contains the pollen grains which produce the male sex cells. |
1. B | Filament | The filament supports the anther. |
2. | Carpel | The carpel is the female reproductive part of the flower. It consists of the stigma, style and ovary. |
2. A | Stigma | The stigma is the sticky bulb at the centre of a flower that catches pollen. |
2. B | Style | The style holds up the stigma. |
2. C | Ovary | The ovary contains the female sex cells (eggs - part 3.) |
4. | Sepal | The sepals are green and resemble small leaves that protect the flower when it is a bud. |
5. | Petal | Petals are modified leaves that surround the flower. They are often brightly coloured to attract insects needed for pollination. |
Pollination
Flowers contain both pollen and eggs which combine to make seeds. The seeds then grow into new plants. Pollination occurs when pollen is transferred from the anther to the stigma. This process can happen in two ways; self-pollination or cross-pollination.
Self-pollination
When the pollen is transferred from the anther to the stigma of the same plant.
Cross-pollination
When the pollen is transferred from the anther of one plant to the stigma of a different plant. This can be aided by the wind or insects.
Insect pollination
Insects are attracted to flowers that are scented and have brightly coloured petals. Some flowers have nectaries, which are glands that produce a sugary liquid for insects to feed on. Whilst insects feed, pollen sticks to them and when they move to a new flower, the insect will transfer the pollen to the stigma as it feeds.
Wind pollination
The stamen of the flower is blown in the wind and pollen is released into the air. The wind carries the pollen to the stigma of another flower. Flowers that pollinate this way are often duller in colour and do not have a strong scent.