Final answer:
The bending of the glycosidic bond in glycolysis is an example of an exergonic reaction that requires a high-energy intermediate. The activation energy is the energy required to initiate the transition from reactants to products in a chemical reaction. Understanding these concepts helps explain why exergonic reactions still require an initial energy input.
Step-by-step explanation:
An exergonic reaction that requires a high-energy intermediate is the bending of the glycosidic bond. This is seen in the process of glycolysis, where glucose is broken down into fructose. In this reaction, ATP is required to phosphorylate glucose, creating a high-energy but unstable intermediate. This intermediate, fructose, is necessary for glycolysis to proceed.
The activation energy is the small amount of energy required to overcome an activation barrier and initiate a chemical reaction. In exergonic reactions, like the bending of the glycosidic bond, the transition state is a high-energy, unstable state that requires an energy input to achieve the contorted state necessary for the reaction to occur. Once the high-energy intermediate is formed, the reaction proceeds to the next steps and releases energy.