Student in the Lab: Bigger Scope

Photography by Dawn Raja Somu, graduate student,
Charles E. Schmidt College of Science

This Time It's Mineral: As sharks swim, their cartilaginous vertebral column bends and deforms, much like a spring — absorbing and releasing energy. Shark vertebrae are particularly interesting due to the interplay between mineralized (hard) and unmineralized (soft) cartilage. Since the structure and properties of biomaterials at the nanoscale influence their response to stresses, we investigate the arrangement of biominerals within fibers of shark vertebral cartilage. From this, we can gain insight into how the interaction between biomineral and collagenous material at the microscopic scale influences bulk material properties and the macroscale swimming efficacy of sharks. Here, we look at mineralization patterns in the vertebral cartilage of blacktip sharks (Carcarhinus limbatus). Mineralized blocks from 1-inch diameter vertebrae were prepared into 70-nanometer slices and imaged using FAU’s Jeol 1400 flash transmission electron microscope. Image colorized to emphasize the amount, shape, size, and orientation of nanocrystalline apatite mineral within the collagen network. Image width: 70μm