Extracellular matrix (also known as ‘ground substance’) is made up of scaffolding of fibres made of a variety of proteins (such as elastin or collagen) and polysaccharides and water (90%). The composition of the extracellular matrix, determines the properties of the connective tissue. For example, if the matrix is calcified, it can form bone or teeth. Specialised forms of extracellular matrix also make up tendons, cartilage,the lamina propria of the vocal folds. General connective tissue is either loose, or dense, depending on the arrangment of the fibres. It is made and replenished by specialized fibroblasts.