Models following the power law approach represent the lumped effects of types of signaling molecules on bone cell populations through the exponent terms in the power law functions. In the case of the model, signaling molecules are grouped into general autocrine and paracrine signaling terms. The autocrine terms encompass all the signals released for self-regulation, e.g., osteoclastderived signals that regulate the osteoclast population. The paracrine terms encompass all the signals other cells release, e.g., osteoblast-derived signals that regulate the osteoclast population. The general form for describing bone cell dynamics following the power law approach is