AP BIOLOGY

Detailed explanation-1: -The ETC is a collection of proteins bound to the inner mitochondrial membrane and organic molecules, which electrons pass through in a series of redox reactions, and release energy. The energy released forms a proton gradient, which is used in chemiosmosis to make a large amount of ATP by the protein ATP-synthase.

Detailed explanation-2: -The proton gradient produced by proton pumping during the electron transport chain is used to synthesize ATP. Protons flow down their concentration gradient into the matrix through the membrane protein ATP synthase, causing it to spin (like a water wheel) and catalyze conversion of ADP to ATP.

Detailed explanation-3: -The primary function of the electron transport chain is to generate an electrochemical gradient. It drives the synthesis of ATP during cellular respiration and photosynthesis in mitochondria and chloroplasts, respectively. It is used in cellular respiration.

Detailed explanation-4: -The proton gradient (ƊpH) functions as an intermediate storage of the harvested light energy and drives ATP synthesis as protons pass across the membrane through the chloroplast cpATP synthase.

Detailed explanation-5: -The function of ATP synthase is to synthesize ATP from ADP and inorganic phosphate (Pi) in the F1 sector. This is possible due to energy derived from a gradient of protons which cross the inner mitochondrial membrane from the intermembrane space into the matrix through the Fo portion of the enzyme.