Which is NOT a function of bones?

The appropriate choice highlights that calcium absorption is not a function of bones. While bones play a crucial role in storing calcium and maintaining calcium homeostasis in the body, they do not perform the process of calcium absorption directly. The absorption of calcium occurs primarily in the intestines, facilitated by vitamin D, where dietary calcium is taken into the bloodstream.

In contrast, bones serve several key functions such as providing support and structure to the body, protecting vital organs from injury, and forming blood cells in the bone marrow through a process known as hematopoiesis. These essential roles underscore the multifaceted importance of the skeletal system in maintaining health and bodily functions.