In cartilage histology, which zone surrounding a chondrocyte is rich in proteoglycans?

In cartilage histology, which zone surrounding a chondrocyte is rich in proteoglycans?

• A. Territorial zone
• B. Interterritorial zone
• C. Perichondrium
• D. Calcified cartilage

Answer: (A)

In cartilage, the immediate matrix around a chondrocyte is called the territorial matrix. This zone is rich in proteoglycans, which are highly sulfated and carry negative charges. Their abundance gives the territorial matrix a dense, basophilic halo around each lacuna and makes it stand out as the proteoglycan-rich region. The surrounding interterritorial matrix, by contrast, has relatively fewer proteoglycans and more fibrous collagen, giving it a different staining and appearance. The perichondrium lies outside the cartilage itself, as a fibrous sheath that contains blood vessels and chondrogenic cells, not the matrix directly around a chondrocyte. Calcified cartilage refers to the mineralized portion of cartilage, which is not the proteoglycan-rich zone surrounding the chondrocyte.

In cartilage, the immediate matrix around a chondrocyte is called the territorial matrix. This zone is rich in proteoglycans, which are highly sulfated and carry negative charges. Their abundance gives the territorial matrix a dense, basophilic halo around each lacuna and makes it stand out as the proteoglycan-rich region. The surrounding interterritorial matrix, by contrast, has relatively fewer proteoglycans and more fibrous collagen, giving it a different staining and appearance.

The perichondrium lies outside the cartilage itself, as a fibrous sheath that contains blood vessels and chondrogenic cells, not the matrix directly around a chondrocyte. Calcified cartilage refers to the mineralized portion of cartilage, which is not the proteoglycan-rich zone surrounding the chondrocyte.