Chapter 14: Energy Generation in Mitochondria and Chloroplast

14.1.k List the components of the electron transport chain in their order of operation, including mobile electron carriers, and describe the functions of each.

1.) NADH Dehydrogenase Complex: accepts NADH's e-, p+ pump 2.) Ubiquinone(Mobile Carrier):Ferries e-; accepts FADH2's e- 3.) Cytochrome c Reductase Complex: p+ pump 4.) Cytochrome c(Mobile Carrier): Ferries e- 5.) Cytochrome c Oxidase Complex: p+ pump

14.0.a Identify the molecule that serves as the main source of chemical energy in a cell.

ATP

14.0.b Differentiate between the mechanisms of ATP production by glycolysis and by oxidative phosphorylation.

Glycolysis breaks down glucose to produce ATP, whereas Oxidative phosphorylation uses proton gradient to synthesize ATP

14.1.f Describe the structure of a mitochondrion and distinguish the functions and compositions of its different membranes and compartments.

Outer mem: Permeable, Porins Inner mem: Cristae, where oxi. phosphorylation occurs. Matrix: contains multiple enzy. to r(x)s Intermem. Space: Several enzy. that use ATP to transport through the cell.

14.1.q Outline how the electrochemical proton gradient is used to drive the transport of metabolites across the inner mitochondrial membrane in eukaryotic cells

P+ gradient is used to drive coupled transport processes, such as pyruvate and phosphate.

14.1.m Recall the direction in which protons are pumped across the inner mitochondrial membrane.

Protons are pumped from the matrix to intermem. space

14.1.l Compare the electron affinities of the components of the electron transport chain, and describe the change in energy of electrons as they move along the chain.

The electron pass through e- carriers with w/ weak e-affinity to a stronger e- affinity, until picked up by oxygen.

14.2.i Name the atoms or molecules that are oxidized or reduced by cytochrome c oxidase.

The mobile carrier cytochrome c is oxidized when Complex cytochrome c oxidase takes its e-

14.2.e Explain why NADH does not donate its electrons directly to molecular oxygen in living systems.

Would result in loss of energy (heat), but instead it is stored in the inner mem.' p+ gradient.

14.1.h Recall the activated carriers, generated by the citric acid cycle, that will transfer high-energy electrons to the electron transport chain.

NADH & FADH2 transfer e-

14.1.i Outline the process that allows much of the energy contained in the high-energy electrons of activated carriers to be stored in the high-energy phosphate bonds of ATP.

NADH and FADH2 drop off their hi-energy electrons, the energy release is used for the phosphorylation of ATP through energy conversion processes in the inner mitochondrial membrane.

14.1.s Compare where electrons donated by NADH and FADH2 enter the respiratory chain, and relate how much ATP is ultimately produced by each activated carrier.

NADH enters by NADH dehydrogenase complex, makes 2.5 ATP FADH2 enters by Ubiquonine (mobile carrier), makes 1.5 ATP

14.2.c Relate redox potential to electron affinity and describe how the redox potentials of reduced/oxidized NADH and oxygen/water align with their functions in the respiratory chain.

NADH is oxidized as it loses its e-

14.1.g Review how pyruvate move from the cytosol to the mitochondrial matrix, and identify the metabolic intermediate into which its converted before entering the citric acid cycle.

Pyruvate goes through the porin of O.M. and through I.M- is converted to Acetyl CoA in Matrix.

14.2.d Estimate the number of ATP molecules that could be synthesized from the energy released by the transfer of two electrons from NADH to molecular oxygen.

Since two e- will pump 6 p+, which produce one ATP per p+, 6 ATP can be made.

14.0.e Summarize the stages involved in generating ATP by oxidative phosphorylation.

Stage 1: Energy of electron chain transport is used to pump protons (H+) across the membrane. Stage 2: Energy in the proton gradient is harnessed by ATP synthase to make ATP

14.1.n Review the membrane potential across the inner mitochondrial membrane, and state in which direction it is energetically favorable for protons to flow.

The p+ create a mem. potential across inner mem.: Matrix side becomes more (-) and intermem. becomes more (+). Its favorable to flow back to the Matrix.