Final answer:
Osteolysis is a process in which calcium is released from bones and enters the bloodstream. This process is mediated by osteoclasts and is regulated by parathyroid hormone (PTH) and vitamin D. PTH stimulates osteoclasts to resorb bone and release calcium into the blood, while also promoting calcium reabsorption by the kidneys and enhancing calcium absorption from the intestine.
Step-by-step explanation:
Osteolysis is a process that results in the liberation of calcium from bones and its entry into the bloodstream. This process is mediated by osteoclasts, which are multinucleated cells that play a key role in bone resorption. When calcium levels in the blood are low, cells of the parathyroid gland release parathyroid hormone (PTH), which stimulates osteoclasts to resorb bone and release calcium into the blood. PTH also promotes the reabsorption of calcium by the kidneys and stimulates the synthesis of vitamin D to enhance calcium absorption from the intestine.