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Structure of an insect-pollinated flower

Reproduction · Sexual reproduction in plants · note 1 of 5

Structure of an insect-pollinated flowerSpec 16.3.1, 16.3.2

In short

An insect-pollinated flower has a male part, the stamen, and a female part, the carpel. The anther in the stamen produces pollen grains containing the male gametes, and the filament holds it up. The stigma receives pollen, the style holds it up, and the ovary contains ovules, which develop into seeds after fertilisation. Petals attract insects.

You must be able to identify, and draw, the parts of an insect-pollinated flower, and state what each part does. The stamen is the male part and the carpel is the female part.

Half-flower of an insect-pollinated flower with labels: petal, sepal, stamen (anther and filament), and carpel (stigma, style, ovary and ovules inside the ovary). (opens full size in a new tab)
Half-flower of an insect-pollinated flower. The stamen (anther and filament) is the male part; the carpel (stigma, style, ovary and ovules) is the female part.
Parts of an insect-pollinated flower and their functions
PartFunction
SepalProtects the flower in the bud
PetalBrightly coloured, to attract insects
StamenMale part of the flower; made of an anther and a filament
AntherProduces pollen grains, which contain the male gametes
FilamentHolds the anther up
CarpelFemale part of the flower; made of the stigma, style, ovary and ovules
StigmaReceives pollen grains; often sticky so that pollen grains stay on it
StyleHolds up the stigma
OvaryContains the ovules
OvuleContains the female gamete (egg cell); after fertilisation it develops into a seed
Common mistake:

The anther makes the pollen. The stigma only receives it. Do not mix up the stamen (male) and the carpel (female).

Practical skill:

When you draw a flower, use a sharp pencil and a single clear line. Draw it large, do not shade, and label with straight lines that do not cross. Label every part in the list above.

Written and checked against the Cambridge IGCSE Biology (0610) specification · Updated October 2026

Frequently asked questions

What is the difference between pollination and fertilisation?

Pollination is the transfer of pollen grains from an anther to a stigma, while fertilisation is the fusion of a pollen nucleus with a nucleus in an ovule. Pollination happens first. Only after pollen reaches the stigma can a pollen tube grow down to the ovule, so that the nuclei can fuse.

How are wind-pollinated flowers adapted?

Wind-pollinated flowers have anthers hanging outside the flower on long filaments, so the wind can blow the pollen away. Their stigmas are large and feathery and hang outside, to catch pollen from the air. Petals are small, dull or absent, with no nectar, and they make very large numbers of small, light, smooth pollen grains.

How does a pollen tube grow?

Supplement A pollen tube grows out of a pollen grain after it lands on the stigma of a flower of the same species. The tube grows down through the style towards the ovary and enters an ovule. The pollen nucleus passes down the tube and fuses with the nucleus of the egg cell, which is fertilisation.

All 5 questions on Sexual reproduction in plants