False-colour scanning electron micrograph of pollen from a rhododendron Rhododendron ponticum. Four grains of pollen group together to form a tetrad.

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False-colour scanning electron micrograph of pollen from a rhododendron Rhododendron ponticum. Four grains of pollen group together to form a tetrad. The tetrads are loosely connected to each other by elastic viscin threads, so that the pollen is released in strings or clumps which stick to the body hairs of insects. The insects fly to other flowers to feed & so pollen is transferred. When the pollen grains, containing the male gametes, land on the stigma of a flower, they germinate. A pollen tube grows out from the grain, through the stigma, to the ovary. The male nuclei pass down the tube, fertilize the ovules & a seed is formed. Magnification: X60 at 35mm size.

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Size: 3566px × 5066px
Photo credit: © R.E.LITCHFIELD/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: botany, nature, plant, plants, pollen, ponticum, reproduction, reproductive, rhododendron, type