Sea urchin spine. Polarised light micrograph of a cross-section through a spine from an Echinus sea urchin. Sea urchin spines consist of supporting ca

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Sea urchin spine. Polarised light micrograph of a cross-section through a spine from an Echinus sea urchin. Sea urchin spines consist of supporting calcareous radial plates, which run the length of the spine, embedded in a reticulate calcareous and organic matrix. The concentric layers indicate the age of the spine, in a manner similar to that of the growth rings of trees. Muscles attached to the base of the spine allow the spine to be moved. Such spines are typically a few millimetres across.

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Size: 4606px × 4563px
Photo credit: © DR KEITH WHEELER/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: animal, biological, biology, calcareous, calcium, cellular, cross-section, cut, cut-, cut-outs, cutout, cutouts, echinus, fauna, light, lm, marine, material, micrograph, microscope, microscopy, mineral, nature, outs, plm, polarised, polarized, sea, section, sectioned, spine, transverse, urchin, wildlife, zoological, zoology