Kate Walton, Graduate Student, Cell Biology, Duke University

The inner beauty of the sea urchin embryo is revealed here in multiple colors. The skeleton (shown in turquoise) is composed of individual cells that become mineralized to provide the outer framework of the embryo. Supported by the skeleton, the gut of the embryo is shown in yellow and the muscle is stained purple. The elaborate organization of the muscle can be seen in the perfectly organized striations of muscle surrounding the foregut, which allows the embryo to swallow food. The outline of the gut sphincters can be seen in pink. At the tip of the embryo are 21 muscles that do not have a known function, but are suspected to help the embryo steer as it swims in search of food.