Periwinkle flower pollination. Coloured scanning electron micrograph (SEM) of a grain of pollen (lower left) on the stigma of a periwinkle flower (family Apocynaceae). The pollen grain,which contains male genetic material,has become trapped by the stigma's papillae (hair-like structures,pink). The stigma is part of the female reproductive structure (pistil),which is formed from one or more carpels. Each carpel consists of a stigma,a style and an ovary (not seen). If the female sex cells (ovules) in the ovary become fertilised by the pollen's genetic material,the carpel may ripen to produce a fruit containing seeds. Magnification: x70 at 6x7cm size | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Nishinaga, Susumu |
Taille de l’image : | 3858 px × 3116 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |