Which term means membrane inside the bone cavity?

Which term means membrane inside the bone cavity?

• A. Epiphysis
• B. Diaphysis
• C. Perichondrium
• D. Endosteum

Answer: (D)

Endosteum is the membrane that lines the inner surfaces of bone, especially the medullary (bone marrow) cavity. This thin, vascularized layer houses osteogenic cells that can become osteoblasts or osteoclasts, supporting bone growth, repair, and remodeling from the inside. The other terms refer to other aspects of bone or cartilage: epiphysis and diaphysis are parts of a long bone (the ends and the shaft, respectively), while perichondrium surrounds cartilage rather than lining the inside of a bone.

Endosteum is the membrane that lines the inner surfaces of bone, especially the medullary (bone marrow) cavity. This thin, vascularized layer houses osteogenic cells that can become osteoblasts or osteoclasts, supporting bone growth, repair, and remodeling from the inside. The other terms refer to other aspects of bone or cartilage: epiphysis and diaphysis are parts of a long bone (the ends and the shaft, respectively), while perichondrium surrounds cartilage rather than lining the inside of a bone.