Polarised light micrograph of a transverse cross section through the stalk of an evening primrose (Oenothera sp.) showing raphides. Raphides are calcium oxalate crystals with needle-like projections. They are a defence mechanism against predators. Magnification: x372 when printed 10 cm wide.

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Size: 6544px × 3985px
Location:
Photo credit: © MAREK MIS/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: -, anatomy, biological, biology, botany, calcium, cells, crystals, evening, light, lm, micrograph, microscopy, nature, oenothera, oxalate, plant, polarised, polarized, primrose, raphide, raphides, stalk, stem, suncups, sundrops, tissue, tissues