In Normal Adult Bones

Question

In normal adult bones,
A) there is no turnover of minerals.
B) a portion of the protein and mineral content is replaced each year.
C) osteoblast activity exceeds osteoclast activity, once bone has been formed.
D) osteoclasts continue to be active long after osteoblast activity ceases.
E) exercise will have no effect on bone remodeling.

Accepted Answer

In normal adult bones, a portion of the protein and mineral content is replaced each year through bone remodeling. This process involves the activity of both osteoblasts (which form new bone) and osteoclasts (which break down old bone). The balance between these two activities determines whether bone mass increases, decreases, or stays the same. Exercise can stimulate bone remodeling and lead to increased bone mass. Therefore, option B is the best choice. Options A, C, and D are incorrect, as they do not accurately describe the process of bone remodeling in normal adult bones. Option E is also incorrect, as exercise can have a positive effect on bone remodeling.