Question

How does bone serve as a "calcium bank" for the body? Describe the role of vitamin D and specific hormones in making “deposits” and “withdrawals” from the calcium bank.

Answer 1

Body needs calcium to build and maintain bones.

Heart, muscles and nerves also need calcium to function properly.

Calcium with vitamin D benefit to bones also protecting against cancer, diabetes and high blood pressure.

Bone as calcium bank:

If the blood calcium level falls, the parathyroid glands release Parathyroid hormone into the blood and release calcium from the bone surfaces.

In contrast when calcium level increase in the the blood calcitonin signals to slow down removal of calcium from bone, this action tends to lower levels of blood calcium.

Maximum calcium stored in bones & teeth.

Calcitriol hormone derived from vitamin D acts on the gut to increase absorption of dietary calcium. In such way bones can deposite,store & withdraw the calcium from bones.