Images Dated 15th May 1998

Sem of pollen from daisy

Daisy pollen. Coloured scanning electron micrograph (SEM) of two pollen grains of the common daisy, Bellis perennis. The outer wall (exine) of each grain has spiky projections. These spines catch in the body hairs of pollinating insects. The insects then fly to other flowers and so pollen is transferred. Pollen contains the male reproductive cells of the plant. When the pollen grain, containing male gametes, lands on the stigma of a flower, it germinates. A pollen tube grows down through the stigma, to the ovary. Male nuclei pass down the tube, fertilize the ovules and a seed is formed. Magnification: x1, 400 at 6x7cm size. Magnification: x3, 000 at 5x6 inch size

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