endergonic

Examples of endergonic in the following topics:

• Free Energy

  • These chemical reactions are called endergonic reactions; they are non-spontaneous.
  • An endergonic reaction will not take place on its own without the addition of free energy.
  • Therefore, the chemical reactions involved in anabolic processes are endergonic reactions.
  • Exergonic and endergonic reactions result in changes in Gibbs free energy.
  • Exergonic reactions release energy; endergonic reactions require energy to proceed.

• Activation Energy

  • Activation energy must be considered when analyzing both endergonic and exergonic reactions.
  • Cells will at times couple an exergonic reaction $(\Delta G<0)$ with endergonic reactions $(\Delta G>0)$, allowing them to proceed.
  • The free energy released from the exergonic reaction is absorbed by the endergonic reaction.
  • Whether the reaction is exergonic (ΔG<0) or endergonic (ΔG>0) determines whether the products in the diagram will exist at a lower or higher energy state than the reactants.
  • In this endergonic reaction, activation energy is still required to transform the reactants A + B into the product C.

• ATP: Adenosine Triphosphate

  • Cells couple the exergonic reaction of ATP hydrolysis with endergonic reactions to harness the energy within the bonds of ATP.
  • ATP provides the energy for both energy-consuming endergonic reactions and energy-releasing exergonic reactions, which require a small input of activation energy.
  • Cells couple the exergonic reaction of ATP hydrolysis with the endergonic reactions of cellular processes.
  • By donating free energy to the Na+/K+ pump, phosphorylation drives the endergonic reaction.
  • In this example, the exergonic reaction of ATP hydrolysis is coupled with the endergonic reaction of converting glucose for use in the metabolic pathway.

• Spontaneous and Nonspontaneous Processes

  • An endergonic reaction (also called a nonspontaneous reaction or an unfavorable reaction) is a chemical reaction in which the standard change in free energy is positive, and energy is absorbed.
  • Endergonic reactions can also be pushed by coupling them to another reaction, which is strongly exergonic, through a shared intermediate.Saul Steinberg from The New Yorker illustrates a nonspontaneous process here.

• ATP in Metabolism

  • In this way, ATP is a direct link between the limited set of exergonic pathways of glucose catabolism and the multitude of endergonic pathways that power living cells.
  • During an endergonic chemical reaction, ATP forms an intermediate complex with the substrate and enzyme in the reaction.

• Solvent Effects

  • These different entropy changes are incorporated in the free energy of solution, which is exergonic for NaCl, but endergonic for CaF2.