How does atp become adp

Some of this energy is trapped in molecules of ATP, and some is lost in the form of heat. Each ATP molecule can then be transported elsewhere within the cell and used where needed.

The energy-carrying part of an ATP molecule is the triphosphate "tail". Three phosphate groups are joined by covalent bonds. The electrons in these bonds carry energy. Within the power plants of the cell mitochondria , energy is used to add one molecule of inorganic phosphate P to a molecule of adenosine diphosphate ADP.

At the energy-requiring site, the last phosphate group in the tail is broken off and the energy in the bond liberated. The ADP and the phosphate are then free to return to the power plant and be rejoined. In this example, the exergonic reaction of ATP hydrolysis is coupled with the endergonic reaction of converting glucose for use in the metabolic pathway.

Privacy Policy. Skip to main content. Search for:. ATP: Adenosine Triphosphate. Key Takeaways Key Points Adenosine triphosphate is composed of the nitrogenous base adenine, the five-carbon sugar ribose, and three phosphate groups. The energy released from the hydrolysis of ATP into ADP is used to perform cellular work, usually by coupling the exergonic reaction of ATP hydrolysis with endergonic reactions.

Sodium-potassium pumps use the energy derived from exergonic ATP hydrolysis to pump sodium and potassium ions across the cell membrane while phosphorylation drives the endergonic reaction. Key Terms energy coupling : Energy coupling occurs when the energy produced by one reaction or system is used to drive another reaction or system. Licenses and Attributions. CC licensed content, Shared previously. Buy why? Here's an analogy. Think about lighting a campfire.

What do you need? You need fuel the wood , you need heat it's harder to light a fire when it's cold , and you need oxygen because another word for burning is " oxidizing " and, as you might guess, it can only occur in the presence of oxygen. Oxidizing something causes it to lose electrons, which means that energy the electrons is released when you oxidize, or burn, a fuel. Your food is your fuel. You burn the fuel for energy. You need the oxygen to burn the fuel.