Pollination
KS3 Biology Reproduction Pollination
Pollination is the process by which pollen is transferred from the male anthers of a flower to the
female stigma of a flower. This process is essential for the reproduction of plants and is typically
carried out by insects, birds, small mammals or the wind.
Pollen comes in many sizes and forms, depending on the plant species; for example:
Some pollen grains are small and lightweight, allowing them to be transported easily by
the wind.
Some pollen grains are larger and sticky, with spikes or other structures that help them
attach to insects.
In wind-pollinated plants, the pollen produced by the anthers is released into the air and carried
by the wind to other plants, where it may be caught by the stigma. In insect-pollinated plants,
pollen is transferred from flower to flower by insects. They visit the flowers for nectar or to feed
on pollen.
The table below compares the properties of insect-pollinated plants and wind-pollinated plants.
Feat
Wind pollinated Insect pollinated
ure
Petal Small dull petals, as there is no need to Brightly coloured petals to help attract
s attract insects pollinating insects
Nect They produce nectar, which is a sugary fluid
Do not produce nectar
ar to attract bees
Amo Produces large amounts of pollen – They produce smaller amounts of pollen, as
unt However, most pollen grains will not get to insects are efficient at transferring pollen
of
Polle
n another flower
grain
s
Hangs outside of the flower, attached to the
Anth Held firmly inside the flower, so any landing
long filaments, so the pollen can be taken
ers insects will brush against it
away by the wind
Feathery or sticky and hanging outside of
Stig
the petals to make it easier to trap pollen that Small and held inside the flower
ma
is carried by the wind
Types of Pollination
There are two main types of pollination:
Self-pollination – Occurs when the pollen from the anther of a flower is transferred to
the stigma of the same flower.
Cross-pollination – Occurs when pollen is transferred from the anther of one flower to
the stigma of a different flower, usually of the same species.
