Question

please help with question 3. parts a,b,c,d,e

electron transport chain FMN donanes into an Fes cemer. How is this possible if the iron edov pair is Fe"Te"(le- carrier)? ochondrial 2 (5 The energy for the synthesis of ATP in the mitochondrion comes frem the relesse of an electrochemical gradient. From where does the energy for the fiormation of the gradient come 3. (15) In the cartoon" of a mitochondrion, draw anows inner membranes, the matrix. and the intermembrane space. Also inda le drawing an oriented represensation of the Fl (Nolly pop) portion conn and label to indicate the outer and indicate the ATP synthase by connected to the membee a. Which compartment increases in pH as electron transpoct begins? b. In which compartment is NADH being used? c. In which compartment is ATP being generated? d. How would the pH in the intermembrane space change upon addition of a coupling factor inhibitor? Briefly explain your answer e. How would the pH in the intermembrane space change upon addition of an uncoupler? Briefly explain your answer

Answer 1

Answer a. Protons from the mitochondrial matrix are transported uphill across the inner mitochondrial membrane and a proton concentration gradient forms across it. Because the outer membrane is freely permeable to protons, the pH of the mitochondrial matrix is higher (i.e., the proton concentration is lower) than that of the cytosol and intermembrane space or in other words we can say that the pH of the matrix starts to increase as the electron transport begins because the protons are pumped from matrix to intermembrane space.

Space Outer Membrane. MITOCHONOAIA

Ans b. NADH is used in the matrix.

Ans c. ATP is generated in the matrix.

Ans e. Uncouplers in mitochondria inhibit the coupling between the electron transport and phosphorylation reactions thereby inhibiting the ATP synthesis without affecting the respiratory chain and ATP synthase (H(+)-ATPase). Basically, what an uncoupler does is it creates a channel or a pore which transfers the protons from the intermembrane space into the matrix. Thus, the pH of the intermembrane space will increase as the H+ will again move back to the matrix.