Mandible, TMJ, Bone Modeling Practice Test

Spongy bone is the type located in the interior of bones and helps keep them light. Its structure is a lattice of trabeculae—thin rods and plates—that create many tiny spaces. Those spaces are often filled with red bone marrow, which lowers overall weight while still providing a supportive framework. The trabeculae align along the lines of mechanical stress, giving strength where it’s most needed without adding bulk. You’ll find this porous tissue in the ends of long bones and within vertebrae, while the dense outer layer, compact bone, forms the heavy shell around the outside. This interior, lightweight design is why spongy (trabecular) bone fits the description.