Sori on fern leaf. Macrophotograph of "sori" spore containing structures on leaves of the male fern Polystichum filix-mas. Sori occur typically on the underside of fern leaves,and they consist of clusters of sporangia (as seen here). Each sporangium contains many spores. When the spores are ready for release,the covering (indusium) over each cluster of sporangia uncurls in dry conditions. This drying also occurs in the wall of the sporangium which eventually,due to tension,splits and catapults spores away from the plant. Spores germinate on the ground to form the prothallus of a new fern plant | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Nuridsany, Claude / Perennou, Maria |
Taille de l’image : | 3573 px × 2480 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : |
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