Collagen fibrils cartilage

The polypeptide precursors of the collagen molecule are formed in fibroblasts (or in the related osteoblasts of bone and chondro blasts of cartilage), and are secreted into the extracellular matrix. After enzymic modification, the mature collagen monomers aggre gate and become cross-linked to form collagen fibrils. 

Cartilage and basement membranes. Tendons consist largely of collagen, but in most tissues the collagen fibrils are embedded in a matrix of proteoglycans and various other proteins.655-657 Both the core proteins of the proteoglycans and the attached... 

Type II collagen D-periodic fibril Cartilage, vitreous 338 0... 

Figure 1. Articular cartilage is partitioned in three phases, one solid phase and two fluid phases. Each fluid phase contains several species. Some of these species are exchangeable, at least partially water and ions can enter and leave the intrafibrillar space defined by collagen fibrils. Proteoglycans which are macromolecules are too large to be admitted into that space, at least in absence of osteo-arthritis. Water and ions can also be exchanged between the extrafibrillar phase and the exterior.

Figure 3.23. Diagram illustrating the zonal structure of articular cartilage. The superficial zone contains aligned collagen fibrils the intermediate zone contains unoriented collagen fibrils the deep zone contains collagen fibrils perperdicular to the subchondral bone.

Figure 3.24. Diagram of the collagen fibrils in cartilage, collagen fibrils in cartilage are composed of a core of types XI and II collagen with zone type IX on the surface. Collagen fibrils are connected to each other and to the cell surface by proteoglycans.

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