phosphate

Meaning of phosphate: Phosphate is a phosphorus-containing ion essential to bone, cell membranes, and the energy molecule ATP, with levels regulated mainly by the kidneys and parathyroid hormone.

Definition of phosphate

Phosphate is a chemical form of the element phosphorus, consisting of a phosphorus atom bonded to oxygen, that occurs widely throughout the body. It is a major structural component of bone and teeth, where it combines with calcium, and it is also a building block of cell membranes and of DNA and RNA.

Phosphate plays a central role in cellular energy, forming part of adenosine triphosphate, the molecule cells use to store and transfer energy, and the transfer of phosphate groups onto or off proteins is a common way cells switch protein activity on or off. Blood phosphate levels are regulated mainly by the kidneys, working together with parathyroid hormone and vitamin D.

Because phosphate is so closely tied to calcium metabolism and kidney function, abnormal phosphate levels, whether too high or too low, often point toward an underlying problem with the kidneys, parathyroid glands, or bone, and phosphate is a routine component of standard blood chemistry testing.

Used in a sentence

A blood chemistry panel included phosphate along with calcium and kidney function tests.

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Good to know

An abnormal phosphate level on blood testing is usually interpreted together with calcium and kidney function rather than in isolation, since the three are closely linked through the body's hormonal regulation.

Word origin

Where “phosphate” comes from

Formed from Greek phos, meaning light, and phoros, meaning bearer, the roots of phosphorus, so named because the element glows faintly in the dark.

For learning, not diagnosis. This glossary provides general educational information and is not a substitute for advice from a qualified healthcare professional. If you may be experiencing a medical emergency, contact local emergency services.