Which type of cartilage contains dense collagen bundles and is typical of intervertebral discs?

• A. Hyaline Cartilage
• B. Elastic Cartilage
• C. Fibrocartilage
• D. Reticular Cartilage

Answer: (C)

Fibrocartilage is the type that contains dense collagen bundles and is typical of intervertebral discs. Its extracellular matrix is rich in thick collagen fibers, mainly type I, arranged in dense bundles that run parallel to the direction of force. This organization gives fibrocartilage exceptional tensile strength and durability, allowing it to resist compression and shear as the spine moves and bears weight. In intervertebral discs, the outer ring (annulus fibrosus) is made of this fibrocartilage, coordinating with a gelatinous nucleus pulposus to absorb shock. Chondrocytes sit in lacunae among the fibrous matrix, and the tissue often lacks a true perichondrium, reflecting its fibrous, tough nature. By contrast, hyaline cartilage has a smoother, glassy matrix with finer collagen fibers and supports joint surfaces; elastic cartilage contains elastic fibers for flexibility. Thus, the dense collagen bundles defining fibrocartilage explain why it’s the characteristic tissue of intervertebral discs.