Most cultured animal cells Grow Only on Special Solid Surfaces The extracellular matrices in various animal tissues consist of several common components; fibrous collagen proteins hyaluronan(or hyaluronic acid), a large mucopolysaccharide; and covalently linked polysaccharides and proteins in the form of proteoglycans(mostly carbohydrate) and glycoproteins(mostly protein)Most Cultured Animal Cells Grow Only on Special Solid Surfaces • The extracellular matrices in various animal tissues consist of several common components: fibrous collagen proteins; hyaluronan (or hyaluronic acid), a large mucopolysaccharide; and covalently linked polysaccharides and proteins in the form of proteoglycans (mostly carbohydrate) and glycoproteins (mostly protein)