Question

1. Which of the below schematics most accurately depicts the flow of electrons through the electron transport chain? A Complex I-Complex Il-Complex IIl Complex IV Complex → Complex-Complex 111 Complex V C Complex IV-Complex IlI- Complex II ComplexI D Complex Complex Ⅲ→ Complex Ⅳ Complex > 2. Which of the following molecules is NOT an electron carrier that participates in the electron transport chain? A. FMNH2 B. Ubiquinol incorrect C. Cytochrome c D. NADPH 3. What is the final electron acceptor of the ETC in human cells? A. O C. H:O D. NAD . How does the transport of electrons help cells to generate energy? A. In each electron transfer step, heat is generated that is used to power chemical reactions. B. Electrons are transmitted across the cell membrane by the ETC, building up an electrical potential which is used to drive ATP synthesis. C. Protons are transmitted across the mitochondrial membrane by the ETC, building up a gradient which is used to drive ATP synthesis. D. Electron transfer is directly coupled to ATP synthesis. 5. Which statement most accurately describes the function of the Q cycle? A. To regenerate QH2 that is depleted by upstream steps in the ETC B. To transfer a single electron to cytochrome c from the double electron carrier QH2 C. To build up a proton gradient to be used for ATP synthesis D. To transfer a single electron from the double electron carrier QH2 to a semiquinone (QH) 6. Which statement most accurately describes the function of complexes I and II? A. To transfer electrons from universal electron acceptors to cytochromec B. To transfer electrons from universal electron acceptors to coenzyme Q C. To transfer electrons from coenzyme Q to cytochrome c D. To transfer electrons from cytochrome c to oxygern

Answer 1

Answer:

1). D. Complex I & Complex II -----Complex III ----Complex IV

2). B. Ubiquinol

3). A). O2

4). B). Protons are transmitted across the mitochondrial membrane by the ETC, building up a gradient, which is used to drive ATP synthesis.

Explanation:

While electrons are transferred from one carrier to other, proton are pumped from mitochondria matrix to inter membrane space, which causes concentration gradient. To normalize proton concentration gradient, protons again move form inter membrane space to matrix via ATP synthetase. This movement of protons causes to drive ATP synthesis.