Year 1 · Reproduction in plants and animals · Section 6.2

Pollination

Nectar and pollen

Many flowers, such as white dead-nettle, produce nectar, a sweet liquid attracting insects. Honeybees collect nectar and use it to make honey, an energy store for the colony. Bees also collect pollen as food.

While visiting flowers, insects can pick up pollen and carry it to other flowers. Pollination is the transfer of pollen from an anther to a stigma of a flower of the same species.

Other animals, including hummingbirds and some bats, can also act as pollinators.

Cross-pollination and self-pollination

Many flowers contain both stamens and a pistil. Pollen may reach the stigma of the same flower or another flower on the same plant. This is self-pollination.

If pollen reaches a flower on a different plant of the same species, this is cross-pollination.

• Self-pollination: Pollen transfer within the same plant.
• Cross-pollination: Pollen transfer between different plants of the same species, often carried by wind or animals.

Insect-pollinated flowers

Flowers pollinated by insects often have these features:

• Large or conspicuously coloured petals.
• Scent and nectar that attract visitors.
• Pollen that sticks to insects and can be transferred to another flower.

Wind-pollinated flowers

Flowers pollinated by wind often have different features:

• Small, inconspicuous flowers, with reduced or greenish petals.
• Little or no scent and no nectar reward.
• Large quantities of pollen, increasing the chance that some reaches a suitable stigma.
• Exposed anthers and often feathery stigmas that help release or catch airborne pollen.