What is the primary function of the parathyroid gland?

The primary function of the parathyroid gland is to maintain calcium levels in the blood. This gland plays a crucial role in regulating calcium homeostasis, which is essential for various physiological processes, including muscle contraction, nerve function, and blood clotting.

When calcium levels drop too low, the parathyroid gland releases parathyroid hormone (PTH). This hormone functions to increase calcium concentration in the bloodstream by promoting the release of calcium from bones, enhancing reabsorption of calcium in the kidneys, and stimulating the conversion of vitamin D into its active form, which in turn increases intestinal absorption of calcium.

Thus, the parathyroid glands are vital for ensuring that calcium levels remain within a narrow range, which is necessary for maintaining overall health and proper bodily functions.