Which tissue type forms the dense outer layer of a typical long bone?

Which tissue type forms the dense outer layer of a typical long bone?

• A. Spongy bone
• B. Compact bone
• C. Hyaline cartilage
• D. Fibrous bone

Answer: (B)

The dense outer layer is compact bone, also called cortical bone. This tissue forms the hard shell that gives long bones their strength and ability to resist bending under load. In the diaphysis of a long bone, compact bone is organized into osteons with concentric lamellae around a central canal, maximizing rigidity while keeping the bone relatively lightweight. Spongy bone, by contrast, is the lighter, porous interior made of trabeculae and houses marrow. Hyaline cartilage covers joint surfaces (not bone tissue itself) to provide a smooth, low-friction surface. Fibrous bone isn’t a normal tissue type in this context.

The dense outer layer is compact bone, also called cortical bone. This tissue forms the hard shell that gives long bones their strength and ability to resist bending under load. In the diaphysis of a long bone, compact bone is organized into osteons with concentric lamellae around a central canal, maximizing rigidity while keeping the bone relatively lightweight.

Spongy bone, by contrast, is the lighter, porous interior made of trabeculae and houses marrow. Hyaline cartilage covers joint surfaces (not bone tissue itself) to provide a smooth, low-friction surface. Fibrous bone isn’t a normal tissue type in this context.