Question

Dinitrophenol increases the permeability of the lipid bilayer of the inner mitochondrial membrane to protons. Assuming that all other processes are unaffected by this chemical, what effect do you think it will have on the generation of ATP in the mitochondrion?A It will have no effect because protons will still flow down through ATP synthase to generate ATP. B. It will increase ATP production because more protong will be able flow down through ATP synthase. C.It will decrease ATP production because fewer protons will be able flow down through ATP synthase. D.It will have no effect because because the ATP production from the citric acid will be able to make up the E. It will increase ATP production because more protons will be able to enter the intermembrane space for difference to activate ATP synthas

Answer 1

Answer:

The correct answer is : C .It will decrease ATP production because fewer protons will be able flow down through ATP synthase.

Explanation:

• Oxidative Phosphorylation is a process which involves two steps:  

1. Transport of electrons from the reduced compounds like NADH (Nicotinamide adenine dinucleotide hydrogen) and FADH₂ (Flavin adenine dinucleotide dihydrogen) through the electron transport complexes, located in the inner mitochondrial membrane, to oxygen for the generation of water molecules.
2. Synthesis of ATP or adenosine triphosphate from ADP or adenosine diphosphate and inorganic phosphate by an enzyme called ATP synthase which is located in the inner mitochondrial membrane. This enzyme harnesses energy by carrying protons from the inter-membrane space into the mitochondrial matrix and in the process produces ATP.

• Oxidative phosphorylation takes place in the mitochondria, especially involving the inter membrane space, inner membrane and mitochondrial matrix

• During the transport of electrons through the protein complexes (I, II, III, IV) of the electron transport chain a proton gradient is generated across the inner mitochondrial membrane.
• The proton gradient is such that the concentration of protons is more in the inter-membrane space and less in the matrix of the mitochondria.
• This proton gradient provides the energy to the ATP synthase for the synthesis of ATP.
• Dinitrophenol is responsible for making the inner mitochondrial membrane permeable to protons. As a result protons can directly diffuse through the inner mitochondrial membrane from the inter-membrane space into the mitochondrial matrix equalising the concentration of protons across the inner mitochondrial membrane. This causes distortion in the proton gradient.  Hence, protons are no longer available for the ATP synthase to operate and synthesise ATP.