What onzyme turns ADP into ATP? NADH FADH2 ATP Synthase mitochondria

## Step 1<br />The question asks for the enzyme that is responsible for converting ADP (adenosine diphosphate) into ATP (adenosine triphosphate). ATP is the primary energy currency of living organisms and is used in various cellular processes.<br /><br />## Step 2<br />The options provided are NADH, FADH2, ATP Synthase, and mitochondria. NADH and FADH2 are electron carriers involved in cellular respiration, specifically in the electron transport chain. They are not enzymes and do not directly convert ADP into ATP.<br /><br />## Step 3<br />Mitochondria are the organelles in cells where ATP is produced, but they are not the enzymes that convert ADP into ATP.<br /><br />## Step 4<br />ATP Synthase is the enzyme that catalyzes the conversion of ADP into ATP. It is located in the inner mitochondrial membrane in eukaryotic cells and in the plasma membrane of prokaryotic cells. ATP Synthase uses the energy from a proton gradient to drive the synthesis of ATP from ADP and inorganic phosphate.