The direct energy source that drives ATP synthesis during respiratory oxidative P phosphorylation is The thermodynamically favorable transfer of phosphate from glycolysis and the citric acid cycle intermediate molecules of ADP. The final transfer of electrons to oxygen. The thermodynamically favorable flow of electrons from NADH to the mitochondrial electron transport carriers. The difference in H+ concentrations on opposite sides of the inner mitochondrial membrane. Oxidation of glucose to CO_2 and water. Solution Ans. Best option. D. Oxidative phosphorylation means ATP synthase using electro-chemical gradient established during aerobic respiration. The vents in series are- 1. NADH and FADH2 transfer their high-energy electron to the ETC complexes (I- IV) sequentially 2. During electron transfer, the energy of electrons is harvested in form of electro-chemical gradient across the inner membrane. In this process, the matrix protons are transferred into inter- membrane space establishing the electro-chemical gradient or Chemiosmotic potential. 3. The proton gradient in form of electro-chemical gradient or Chemiosmotic potential has high energy content. 4. When the protons flow back into the matric through ATP synthase, their potential energy is harvested in form of ATP. So, Proton gradient acts as the direct (most immediate) source for ATP synthesis during respiratory oxidative phosphorylation. Note: first law of thermodynamics states that “energy can neither be created, nor be destroyed, but can be transformed from one to another form”. TCO2 and H2O formed glucose during photosynthesis and stored solar energy in form of high energy electron (chemical bonds). When glucose is oxidized, the same energy is harvested with lower efficiency..

1. The direct energy source that drives ATP synthesis during respiratory oxidative P
phosphorylation is The thermodynamically favorable transfer of phosphate from glycolysis and
the citric acid cycle intermediate molecules of ADP. The final transfer of electrons to oxygen.
The thermodynamically favorable flow of electrons from NADH to the mitochondrial electron
transport carriers. The difference in H+ concentrations on opposite sides of the inner
mitochondrial membrane. Oxidation of glucose to CO_2 and water.
Solution
Ans. Best option. D.
Oxidative phosphorylation means ATP synthase using electro-chemical gradient established
during aerobic respiration.
The vents in series are-
1. NADH and FADH2 transfer their high-energy electron to the ETC complexes (I- IV)
sequentially
2. During electron transfer, the energy of electrons is harvested in form of electro-chemical
gradient across the inner membrane. In this process, the matrix protons are transferred into inter-
membrane space establishing the electro-chemical gradient or Chemiosmotic potential.
3. The proton gradient in form of electro-chemical gradient or Chemiosmotic potential has high
energy content.
4. When the protons flow back into the matric through ATP synthase, their potential energy is
harvested in form of ATP.
So, Proton gradient acts as the direct (most immediate) source for ATP synthesis during
respiratory oxidative phosphorylation.
Note: first law of thermodynamics states that “energy can neither be created, nor be destroyed,
but can be transformed from one to another form”. TCO2 and H2O formed glucose during
photosynthesis and stored solar energy in form of high energy electron (chemical bonds). When
glucose is oxidized, the same energy is harvested with lower efficiency.