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Specialty Chemistry Forums => Biochemistry and Chemical Biology Forum => Topic started by: bergkamp10 on June 24, 2010, 08:37:15 AM

Title: Bone Hydroxyapatite
Post by: bergkamp10 on June 24, 2010, 08:37:15 AM
Hi everyone, I was wondering if the hydroxyapatite in bone is in dynamic equilibrium with its surroundings. What I mean is would this reaction occur with bone in a normal human body?

Ca10(PO4)6(OH2)  ::equil:: 10Ca2+ + 6PO3- + 2OH-

Thank you in advance! :)
Title: Re: Bone Hydroxyapatite
Post by: Borek on June 24, 2010, 09:49:27 AM
Yes and no. Yes - there exists dynamic equilibrium. No - it is not as simple as the equation you wrote.
Title: Re: Bone Hydroxyapatite
Post by: AWK on June 24, 2010, 09:56:37 AM
Quote
6PO3-

something is missing
Title: Re: Bone Hydroxyapatite
Post by: bergkamp10 on June 25, 2010, 08:19:40 AM
Quote from: Borek on June 24, 2010, 09:49:27 AM
Yes and no. Yes - there exists dynamic equilibrium. No - it is not as simple as the equation you wrote.

Hmm, so lets say this complicated dynamic equilibrium, would Le Chatelier's Principle still apply? During plasma calcium homeostasis, many things occur and one of them is the increase reabsoption of calcium and excretion of phosphate in the kidneys. I was wondering what the mechanism of excreting phosphate would be. My two guesses would be that since calcium and phosphate tend to precipitate, there will be more free calcium or that due to Le Chatelier's Principle, bone will resorb more to release more phosphate ions and calciums ions as well?

Quote from: AWK on June 24, 2010, 09:56:37 AM
Quote
6PO3-

something is missing

Opps, a silly mistake, I missed the sub 4.  :o