What is meant by pollination?

It is the transfer of pollen grains from the anther of a flower to the stigma.

How are the anthers of a wind-pollinated cereal adapted to release pollen into moving air?

They are large and dangle outside the flower on long flexible filaments and pivot freely where they attach, so even a slight air movement shakes them and releases pollen into the moving air.

How is the stigma of a wind-pollinated flower adapted to catch pollen?

It is large and feathery and hangs outside the flower, which gives a very large surface area for filtering pollen grains out of the air as it passes.

Give three features of pollen carried by wind.

It is produced in enormous quantities, and the individual grains are very small, light and smooth so that they are carried a long way on air currents.

OCR A-Level Biology B H422

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Plant Reproduction

Adaptations of flowers for pollination

3 things to know
Components 01, 02 and 03

Overview

Recall questions on pollination and fertilisation, how the anthers, stigmas and pollen of wind-pollinated flowers are adapted, why they lack petals, scent and nectar, how insect-pollinated flowers attract pollinators with nectar guides, pollination of a pea flower by a bee, and dissecting a flower.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Key term

How does a visiting bee pollinate a pea flower?

Key term

Distinguish between pollination and fertilisation in a flowering plant.

Key term

Why do wind-pollinated flowers have no large petals, no scent and no nectar?

Questions from this subtopic

Each one with the model answer underneath.

1
What is meant by pollination?
Model answer
It is the transfer of pollen grains from the anther of a flower to the stigma.
2
Distinguish between pollination and fertilisation in a flowering plant.
Model answer
Pollination is the transfer of a pollen grain onto the stigma, whereas fertilisation is the later fusion of a male gamete delivered by the pollen tube with the female gamete inside the ovule.
3
How are the anthers of a wind-pollinated cereal adapted to release pollen into moving air?
Model answer
They are large and dangle outside the flower on long flexible filaments and pivot freely where they attach, so even a slight air movement shakes them and releases pollen into the moving air.
4
How is the stigma of a wind-pollinated flower adapted to catch pollen?
Model answer
It is large and feathery and hangs outside the flower, which gives a very large surface area for filtering pollen grains out of the air as it passes.
5
Give three features of pollen carried by wind.
Model answer
It is produced in enormous quantities, and the individual grains are very small, light and smooth so that they are carried a long way on air currents.
6
Why do wind-pollinated flowers have no large petals, no scent and no nectar?
Model answer
There is no animal visitor to attract, so producing them would waste resources, and large petals would also shelter the anthers and stigmas from the air flow the plant depends on.

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