Page 21 - 新思维科学学生用书5 样章

1 Life cycles of flowering plants

Why must flowers be pollinated?

Plants reproduce by making seeds. The pollen and eggs join to make seeds in a process

called fertilisation.

Pollination brings pollen from the male anther to the female stigma. This allows the
eggs to be fertilised and seeds to form. Fertilisation happens in the flower’s ovary.

Fertilisation only happens if the pollen and the eggs are from the same kind of flower.
After the egg is fertilised, the petals and stamens of the flower die. The ovary grows and

becomes the fruit. Seeds form inside the fruit. The fruit protects the seeds and helps to

spread them.

Flower

Sepal

Fruit forms from
ovary of flower
Mature fruit

Questions

1 Why do flowers pollinated by insects have brightly coloured, scented petals

and nectar?
2 a Why do flowers pollinated by wind have little colour, no petals or scent?

b Why do flowers pollinated by wind produce lots of dry pollen?

3 How does pollination help the plant reproduce?
4 Explain how pollination is different to fertilisation.

5 a Which part of the flower forms the fruit?
b What are the functions of the fruit?

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