Answer:
The osteoblasts, which should have been building the new bone
Explanation:
Bones are the one of the types of connective tissues and have hard extracellular matrix. Osteoblasts are the cells that serve in formation of extracellular matrix of bones as these cells secrete collagen fibers and inorganic salts present in the matrix of bone. Hence, if a bone is not able to heal after fracture, osteoblast cells should be checked for their activity.
Glycoprotein Cell Receptors, but you can probably just put proteins
the two main skeletal systems to support the tissue of the body is bone and cartilage
hopefully this will help