The article discusses the role of collagenous matrices in cell adhesion and growth. It highlights that many cultured cells, such as fibroblasts, myoblasts, hepatocytes, chondrocytes, and certain epithelial cells, do not directly bind to collagen substrates or plastic surfaces but instead use extracellular glycoproteins like fibronectin to attach. Fibronectin, produced by various cell types, binds to both collagen and tissue culture plastic, mediating cell attachment. The article also explores how different cell types use specific glycoproteins for attachment, such as chondrocytes binding to type II collagen and epithelial and endothelial cells to type IV collagen. Additionally, it covers the structure, biosynthesis, and degradation of collagen, as well as the synthesis of collagen by cultured cells and differentiated cells. The biological effects of collagen matrices, including their influence on cell morphology, migration, and adhesion, are discussed. The article concludes by emphasizing the complex interactions between collagen, attachment proteins, and proteoglycans in maintaining cell function and directing growth and differentiation.The article discusses the role of collagenous matrices in cell adhesion and growth. It highlights that many cultured cells, such as fibroblasts, myoblasts, hepatocytes, chondrocytes, and certain epithelial cells, do not directly bind to collagen substrates or plastic surfaces but instead use extracellular glycoproteins like fibronectin to attach. Fibronectin, produced by various cell types, binds to both collagen and tissue culture plastic, mediating cell attachment. The article also explores how different cell types use specific glycoproteins for attachment, such as chondrocytes binding to type II collagen and epithelial and endothelial cells to type IV collagen. Additionally, it covers the structure, biosynthesis, and degradation of collagen, as well as the synthesis of collagen by cultured cells and differentiated cells. The biological effects of collagen matrices, including their influence on cell morphology, migration, and adhesion, are discussed. The article concludes by emphasizing the complex interactions between collagen, attachment proteins, and proteoglycans in maintaining cell function and directing growth and differentiation.