Notices
Results 1 to 3 of 3

Thread: Adenosine triphosphate: ATP cellular energy

  1. #1 Adenosine triphosphate: ATP cellular energy 
    Forum Cosmic Wizard icewendigo's Avatar
    Join Date
    Jun 2006
    Posts
    2,150
    The bond-breaking in ATP requires initial energy input as does bond-breaking in all chemical reactions, but in the hydrolysis of ATP this input is more than re-paid with the energy of formation of "hydration" bonds between the products (ADP + phosphate) and water. In other words, the hydration process for the phosphate products results in a release of energy that exceeds the amount of energy for breaking the phosphate bonds in ATP, hence resulting in a gain in a net energy release from these two reaction steps.
    So in contact with water ATP breaks and releases energy for the cell? What form energy is that?

    (since its chemical reactions within a cell I wasnt sure if its too chemical for the biology section or too biological for the chemistry section)


    Reply With Quote  
     

  2.  
     

  3. #2  
    Forum Cosmic Wizard i_feel_tiredsleepy's Avatar
    Join Date
    Mar 2008
    Location
    Montreal
    Posts
    2,256
    It isn't the breaking of the phosphate bond that releases energy, it is the subsequent formation of bonds between water and the freed phosphate group and the ADP.

    When speaking of ATP we tend to concern ourselves with the Gibbs free energy, because we are concerned mostly with coupled reactions. Since it has been 5 years since I took a course in thermodynamics, I'll leave it to the real chemist to explain that better.


    Reply With Quote  
     

  4. #3  
    Forum Masters Degree Golkarian's Avatar
    Join Date
    Nov 2008
    Posts
    510
    ADP + phosphate has a lower energy state (it's more stable) than ATP because the free phosphate group has more resonance structures than when it was connected to ATP. This means that the electron density is less concentrated on the phosphate after ATP breaks down. So the energy might come from electron-electron repulsion (a form of chemical energy?) on ATP's last phosphate group. But someone should really check this.
    Reply With Quote  
     

Bookmarks
Bookmarks
Posting Permissions
  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •