AP BIOLOGY

Detailed explanation-1: -During electron transport, energy is used to pump hydrogen ions across the mitochondrial inner membrane, from the matrix into the intermembrane space. A chemiosmotic gradient causes hy drogen ions to flow back across the mitochondrial membrane into the matrix, through ATP synthase, producing ATP.

Detailed explanation-2: -As protons move through ATP synthase, ADP is turned into ATP. The production of ATP using the process of chemiosmosis in mitochondria is called oxidative phosphorylation.

Detailed explanation-3: -The protons return to the mitochondrial matrix through the protein ATP synthase. The energy is used in order to rotate ATP synthase which facilitates the passage of a proton, producing ATP.

Detailed explanation-4: -This enzyme creates a hydrophilic pathway across the inner mitochondrial membrane that allows protons to flow down their electrochemical gradient. As these ions thread their way through the ATP synthase, they are used to drive the energetically unfavorable reaction between ADP and Pi that makes ATP (see Figure 2-27).