What enzyme is responsible for synthesizing ATP from ADP using energy from an electrochemical gradient?

The enzyme responsible for synthesizing ATP from ADP using energy derived from an electrochemical gradient is known as ATP Synthase. This enzyme is crucial in the process of oxidative phosphorylation, which occurs in the mitochondria of eukaryotic cells. During cellular respiration, protons are pumped across the inner mitochondrial membrane, creating an electrochemical gradient (also known as a proton gradient). ATP Synthase utilizes the energy stored in this gradient to catalyze the conversion of ADP and inorganic phosphate into ATP as protons flow back into the mitochondrial matrix through the enzyme.

The specificity of the name "ATP Synthase" reflects its function as a synthase, meaning it facilitates the synthesis of a molecule. This distinguishes it from other enzymes that have different functions in the ATP cycle, such as those involved in hydrolysis or signaling. Thus, the correct choice underscores the specific role ATP Synthase plays in energy production within the cell.