Surface of a water fern (Azolla sp.), coloured scanning electron micrograph (SEM). The leaves of water ferns support colonies of Anabaena azollae, a b

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Surface of a water fern (Azolla sp.), coloured scanning electron micrograph (SEM). The leaves of water ferns support colonies of Anabaena azollae, a blue-green alga that fixes atmospheric nitrogen and enriches the water in which it grows. For this nitrogen-fixing ability, water ferns are grown in rice paddies in India as a fertiliser plant. The roots are unanchored and are generated by multiple divisions in various planes from just one apical cell. Magnification: x70 when printed at 10 centimetres wide.

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Size: 5002px × 3495px
Photo credit: © MARTIN OEGGERLI/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: alga, algae, anabaena, anatomical, anatomy, aquatic, azolla, azollae, biological, biology, botanical, botany, fern, fixing, flora, freshwater, leaf, mutualism, mutualistic, nature, nitrogen, order, plant, salviniales, sem, sp., symbiosis, symbiotic, water, waterplant