Polarised light micrograph of a white sea urchin (Gracilechinus acutus). The test and spines of sea urchins are composed of calcium carbonate. Each sp

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Polarised light micrograph of a white sea urchin (Gracilechinus acutus). The test and spines of sea urchins are composed of calcium carbonate. Each spine articulates with a tubercle on the test. The elaborate structure of the spines when seen in cross section has made them a popular subject for microscopists. Magnification: x68 at 10cm size.

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Size: 3527px × 2516px
Photo credit: © STEVE LOWRY/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: actus, anatomical, anatomy, animal, biological, biology, calcium, carbonate, cross, echinoderm, fauna, gracilechinus, light, micrograph, microscope, microscopic, microscopy, nature, polarised, polarized, sea, section, spine, symmetry, urchin, white, zoological, zoology