Which of the following statements regarding the homeostasis regulation of blood calcium is FALSE? PTH is secreted by the parathyroid glands and raises blood calcium levels that are below 8.5 mg/dL The three main organs that serve as the site for the regulation of blood calcium levels are the bones, the intestines, and the pancreas. Calcitonin inhibits the action of osteoclasts while having no effect on osteoblast activity. This helps to lower the blood calcium level whenever it exceeds 11 mg/dL The homeostasis of blood calcium is regulated by a negative feedback mechanism