These cells form when we are babies and fill and empty as we go through life. They also pad certain organs in the body. Dense tissue owing to the large amounts of collagenous tissue. Tendons and ligaments are the two types of structures containg this tissue. Tendons hold muscle to bone.
Ligaments hold bone to bone.
The chondron is secreted by chondrocytes. Cartilage 2 . Cells called osteocytes deposit a matrix of collagen and calcium-phosphate which harden to form crystals of a substance called hydroxyapatite. Mammalian bone is constructed from repeated units called Haversian Units. The process of making new bone is called ossification .