has part has part has_part only in taxon contributes to morphology of glycosaminoglycan Bilateria skeletal system cartilage tissue http://upload.wikimedia.org/wikipedia/commons/e/ee/Hypertrophic_Zone_of_Epiphyseal_Plate.jpg Previous: "A portion of connective tissue dominated by extracellular matrix containing collagen type II and large amounts of proteoglycan, particularly chondroitin sulfate[GO]. Regular connective tissue, which consists of chondrocytes and related cells, the intercellular matrix of which is chondrified. Examples: hyaline cartilage, fibrocartilage, elastic cartilage[FMA]. an avascular supporting and articular skeletal tissue. It also functions as the primary endoskeletal support in vertebrate embryos. Cartilage is deposited by and is composed of chondroblasts and chondrocytes separated by an extracellular matrix, which may or may not mineralize depending on cartilage type, age, or taxon[Hall and Witten]." See also FMA:71500 Set of cartilages, FMA:55107 Cartilage organ, FMA:12264 Articular cartilage. // elements made from cartilage, cartilage-like, or chondroid tissues evolved in invertebrates[H&W] skeletal tissue