Which term refers to the cavity within the shaft of long bones filled with bone marrow?

Which term refers to the cavity within the shaft of long bones filled with bone marrow?

• A. Medullary Cavity
• B. Axial Skeleton
• C. Appendicular Skeleton
• D. Spongy Bone

Answer: (A)

This question tests your understanding of bone anatomy, specifically the central canal in the shaft of a long bone that houses marrow. The hollow space inside the diaphysis is the medullary cavity, or marrow cavity. It runs through the shaft and is lined by the endosteum. In adults it mainly contains yellow marrow (fat), while red marrow is found in other parts of the skeleton where hematopoiesis occurs. The other terms describe different structures: the axial skeleton includes the skull, spine, and rib cage; the appendicular skeleton covers the limbs and girdles; spongy bone refers to the porous interior located at the ends of bones and within some flat bones, not the central marrow-filled cavity.

This question tests your understanding of bone anatomy, specifically the central canal in the shaft of a long bone that houses marrow. The hollow space inside the diaphysis is the medullary cavity, or marrow cavity. It runs through the shaft and is lined by the endosteum. In adults it mainly contains yellow marrow (fat), while red marrow is found in other parts of the skeleton where hematopoiesis occurs. The other terms describe different structures: the axial skeleton includes the skull, spine, and rib cage; the appendicular skeleton covers the limbs and girdles; spongy bone refers to the porous interior located at the ends of bones and within some flat bones, not the central marrow-filled cavity.