This is this section here. Now the lining of the inner portion of the bone is known as our endosteum, while our outermost lining of the cell, so the membraneous fibrous covering found outside the entire bone is known as our periosteum. Now the periosteum basically is involved in bone healing and bone growth. And that basically means inside the periosteum we have these cells that are capable of differentiating into osteoblasts where osteoblasts are the cells that are involved in bone growth as well as bone healing. Now the periosteum covers the bone so it is also involved in a protective function. It protects our bone and it also serves as the attachment points for tendons that connect muscles to our bones.