ATP refers to Adenosine triphosphate.

It contains ribose sugar, adenine base, and phosphate group, PO4-2

here is a diagram of its molecular structure

so basically, the phosphate group on the far left breaks off when an enzyme tell it to do so. This reaction releases energy. Its tat simple

After it breaks, adenosine diphosphate (ADP) and orthophosphate (HPO4) as the products.

The conversing of ATP to ADP is a cycle, where ADP with energy and that phosphate group can produce ATP.

Therefore, if the phosphate group dont break off, it can store the energy until a enzyme tells it to

It’s stored in the high energy bonds between the phosphates; P-P-P

Yes, there are high energy bonds stored between the phosphates, but the adenosine has something to do with the storage as well, but I don’t remember how, the internet should help you out more than I can. Just search for energy storage in ATP and you should get some helpful sites.

ATP + O2 ➡ ADP + Pi δH = -7.3 kkal/mole (in vitro)
ATP + O2 ➡ ADP + Pi δH = -13.3 kkal/mole (in vivo)

Can anyone explain about this? 😉

Shouldn’t the in vitro energy be bigger than in vivo?

you must understand that it doesn’t store energy, it merely releases energy as the bonds are broken

The concentrations of product and reactant also play a role in the energy released.