Question

5. Describe how the electrochemical gradient generated during the electron- transport chain changes the conformation of the ATP Synthase, enabling it to catalyze the covalent attachment of Pi to ADP to form ATP.

Answer 1

Answer=

The electrochemical gradient generated during the electron- transport chain changes the conformation of the ATP Synthase, enabling it to catalyze the covalent attachment of Pi to ADP to form ATP. is as follows:

1.Most of the free energy released during the oxidation of glucose to CO₂ is retained in the reduced coenzymes NADH and FADH₂ generated during glycolysis and TCA cycle.

2.During respiration ,electrons are released from NADH and FADH₂and eventually are transferred to O₂,forming H₂O.

3.Conversion of 1 glucose molecule to CO₂via glycolytic pathway & TCA cycle yields 10 NADH & 2 FADH₂.

4.There is step by step transfer of electrons via the electron transport chain,allows the free energy in NADH & FADH₂ to be released .

5.At several sites during electron transport from NADH to O₂,protons protons from the mitochondrial matrix are transported uphill across the inner mitochondrial membrane and a proton concentration gradient forms across it.

6.Because the outer membrane is freely permeable to protons,the p^H of the mitochondrial matrix is higherthan that of cytosol & intermediate space.

7.Thus thefree energy released during oxidation of NADH & FADH₂ is stored both as an electric potential and a proton concentration gradient is generated across the inner mitochondrial membrane.

8.The movement of protons back across the inner membrane ,driven by this force,is coupled to the synthesis of ATP from ADP & pi by the ATP synthase.