Question

Which of the following conditions would provide the most favorable conditions for the transport of protons from the mitochondrial matrix to the intermembrane space, in the absence of electron transport? proton gradient (with a higher proton concentration in the intermembrane space than in the mitochondrial matrix) and high ATP/low ADP in the matrix. proton gradient (with a higher proton concentration in the intermembrane space than in the mitochondrial matrix) and low ATP/high ADP in the matrix. proton gradient (with a higher proton concentration in the matrix than in the intermembrane space) and high ATP/low ADP in the matrix. proton gradient (with a higher proton concentration in the matrix than in the intermembrane space) and low ATP/high ADP in the matrix. proton gradient (with a higher proton concentration in the mitochondrial intermembrane space than in the cytosol) and ADP in the cytosol but not in the mitochondrial matrix.

Answer 1

option a will be the correct answer

beacuse electron transport chain has two important functions:

• Regenerates electron carriers. NADH and FADH_22​start subscript, 2, end subscript pass their electrons to the electron transport chain, turning back into NAD^++start superscript, plus, end superscript and FAD. This is important because the oxidized forms of these electron carriers are used in glycolysis and the citric acid cycle and must be available to keep these processes running.

• Makes a proton gradient. The transport chain builds a proton gradient across the inner mitochondrial membrane, with a higher concentration of H^++start superscript, plus, end superscript in the intermembrane space and a lower concentration in the matrix. This gradient represents a stored form of energy, and, as we’ll see, it can be used to make ATP.