How does the skeletal system help maintain calcium levels in the blood stream?

The skeletal system helps maintain calcium levels in the bloodstream primarily through the actions of osteoblasts and osteoclasts. Osteoblasts are responsible for bone formation and can take calcium from the bloodstream to deposit it in bones, while osteoclasts break down bone tissue, releasing calcium back into the bloodstream when needed. This dynamic balance is regulated by hormones such as parathyroid hormone (PTH) and calcitonin, which respond to changes in blood calcium levels to ensure homeostasis. Thus, the skeletal system acts as both a reservoir and a regulator of calcium levels in the body.