It provides the matrix with strength and it's found in connective tissue such as bone, our cartilage, blood vessels and so forth. Now, the next type of molecule that is found inside the extracellular matrix is the Adhesive protein. And we have many different types of Adhesive proteins. So these are basically the proteins that combine, that glue our individual cells together to form our tissues. And some examples include integrates as well as Catherine, and we'll talk more about these types of proteins when we get into biochemistry. Now, the final type of major constituent of the extracellular matrix inside tissues is the proteoglycan.