Which term describes the thin vascular membrane lining the inner surfaces of bone cavities?

Which term describes the thin vascular membrane lining the inner surfaces of bone cavities?

• A. Calcaneus
• B. Endosteum
• C. Crani/o
• D. Osteon

Answer: (B)

Endosteum is the thin vascular membrane that lines the inner surfaces of bone cavities. It covers the medullary (marrow) cavity and the inner surfaces of trabeculae in spongy bone, and it contains osteogenic cells that contribute to bone growth, repair, and remodeling. This inner lining is distinct from the outer covering, the periosteum, which surrounds the exterior of bone. The other terms refer to different structures: calcaneus is the heel bone, crani/o means skull, and an osteon is the microscopic Haversian unit of compact bone.

Endosteum is the thin vascular membrane that lines the inner surfaces of bone cavities. It covers the medullary (marrow) cavity and the inner surfaces of trabeculae in spongy bone, and it contains osteogenic cells that contribute to bone growth, repair, and remodeling. This inner lining is distinct from the outer covering, the periosteum, which surrounds the exterior of bone. The other terms refer to different structures: calcaneus is the heel bone, crani/o means skull, and an osteon is the microscopic Haversian unit of compact bone.