Cambridge O Level Biology · Syllabus 5090 · Development of Organisms and Continuity of Life
Pollination
What is Pollination?
The transfer of pollen grains from the anther of a stamen to the stigma of a carpel. Pollination is a transfer only: no nuclei have fused and no seed exists at this stage, and fertilisation follows later inside the ovule.
This definition is part of the Development of Organisms and Continuity of Life chapter in Cambridge O Level Biology.
Common mistakes with Pollination
- “Fertilisation happens on the stigma.” Say instead Fertilisation happens inside the ovule, at the far end of the journey. Only pollination happens on the stigma.
- “Pollination and fertilisation are the same event.” Say instead Pollination is the transfer of pollen; fertilisation is the fusion of nuclei. A flower can be pollinated without ever being fertilised.
- “Self-pollination is asexual reproduction.” Why wrong Gametes are still made by meiosis and two haploid nuclei still fuse. That is sexual reproduction, regardless of where the pollen came from. Say instead Self-pollination is sexual reproduction with less genetic variation than cross-pollination.
- “Pollination is the fusion of nuclei.” Why wrong That is the definition of fertilisation. At pollination nothing has fused and no offspring exists. Say instead Pollination is the transfer of pollen grains from an anther to a stigma.
Examiner tips on Pollination
- The single most valuable habit in this topic. Before writing any answer that mentions pollination, fertilisation, meiosis or mitosis, say the definition silently to yourself first. Most lost marks in Topic 16 are not gaps in knowledge — they are the right idea attached to the wrong word.
Questions students ask about Pollination
Is pollination the same as fertilisation?
No. Pollination is the transfer of pollen grains from an anther to a stigma. Fertilisation is the fusion of a male nucleus with the female nucleus, and it happens later and elsewhere — inside an ovule, after a pollen tube has grown down the style. A flower can be pollinated and never fertilised, for example if the pollen is from a different species.