Final answer:
An energy diagram for endothermic reactions shows products with more energy than reactants and includes a peak representing activation energy, illustrating that the reaction absorbs energy.
Step-by-step explanation:
An energy diagram for an endothermic biochemical reaction shows the products having more stored energy than the reactants, which means the reaction absorbs energy from its surroundings. This is depicted on the diagram as an upward slope from reactants to products. The activation energy, marked on the diagram, is shown as a peak that must be overcome for the reactants to transform into products. Following the peak (transition state), the products reside at a higher energy level than the reactants, indicating that the overall process requires input of energy and is endothermic.
Potential energy diagrams illustrate this by showing an increase in total potential energy of the system as the endothermic reaction progresses. These diagrams can also identify particular elementary steps in a reaction sequence and their respective activation energies. The enthalpy change (ΔH) for these reactions is positive, as the potential energy of the system goes up, which can also be depicted on these diagrams.