Approximately what percentage of the body's phosphate is bound up in bone and teeth?

1. Phosphate exists in the body in three ionic forms and serves many roles, including in ATP and phospholipids. 2. Most phosphate, like calcium, is stored as part of the mineral matrix of bone and teeth. 3. This stored fraction is 85 percent of the body's phosphate. 4. 25 percent and 50 percent are both different figures a reader might guess from memory, but neither matches the specific figure given here. 5. 99 percent is also incorrect for the same reason: it does not match the specific figure given here. 6. So 85 percent is correct, not the lower or near-total figures offered. _Source: OpenStax Anatomy and Physiology (CC BY 4.0), Ch 26 "Fluid, Electrolyte, and Acid-Base Balance", p.1262 §Phosphate_