Pollen. Coloured scanning electron micrograph (SEM) of a pollen grain of the garden hollyhock,Althaea rosa. Its outer wall (exine) has a spiky structure. When the pollen grain,containing the male gametes,lands on the stigma of a flower of the same species,it germinates. A pollen tube grows from the pollen grain & down to the flower's ovaries. The ovules are then fertilised & a seed is formed. Magnification: x200 at 6x6cm size | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Burgess, Dr. Jeremy |
Bildgröße: | 3730 px × 3715 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |