Final answer:
The inner portion of the periosteum is made up of the osteogenic layer, containing osteoblasts and osteoclasts, which are vital for bone growth and remodeling.
Step-by-step explanation:
The inner portion of the periosteum is primarily made up of osteogenic cells that include osteoblasts and osteoclasts which are essential for bone growth and healing. The periosteum is a fibrous membrane that covers the bone and has two layers: the outer fibrous layer rich in collagen fibers, and the inner cambium layer (or osteogenic layer) which contains the precursor cells necessary for the synthesis and turnover of bone tissue, including osteoblasts (bone formation cells) and osteoclasts (bone resorption cells). Furthermore, the periosteum entrap blood vessels, nerves, and lymphatics, contributing to the blood supply and nourishment of bone.
The inner portion of the periosteum is made of the endosteum. The endosteum is a delicate membranous lining that lines the medullary cavity inside the bone. It is involved in bone growth, repair, and remodeling.