This primary bone is characterized by immature bone trabeculae which are aligned along the direction of traction exerted by the periodontal fibers. Secondary bone can be identified by its osteon-like ...

Primary peritoneal cancer (PPC) is a rare cancer. It starts in the thin layer of tissue lining the inside of the tummy (abdomen). This tissue lining is called the peritoneum. PPC cells are the same as ...

Powered flight has evolved separately in three tetrapod clades: pterosaurs, birds (avian dinosaurs), and bats. To meet the challenges of powered flight, tetrapods acquired structural, mechanical, and ...