oxidative phosphorylation Flashcards
what does electron flow down the electron-transport chain lead to?
the transport of protons across the inner mitochondrial membrane from inside the matrix to the intermembrane space.
What term is used to describe an ATP-generating process in which an inorganic substance such as oxygen serves as the ultimate electron acceptor?
respiration
What organelle is the site of oxidative phosphorylation in eukaryotes?
mitochondria
What is a cytochrome?
a protein that transfers electrons and that also contains a heme prosthetic group
What type of gradient is critical to ATP formation by oxidative phosphorylation?
proton
What type of protein makes the outer mitochondrial membrane relatively permeable?
porin
Which electron carrier has a lipid tail?
coenzyme Q
Which enzyme catalyzes the reduction of oxygen to water?
cytochrome c oxidase
Which enzyme transfers electrons from a membrane-soluble carrier to a water-soluble carrier in the electron-transport process?
Q-cytochrome c oxidoreductase
Which of the citric acid cycle enzymes is also part of an electron-transport complex?
succinate dehydrogenase
What is the net yield of ATP molecules produced during cellular respiration, per molecule of glucose completely oxidized to carbon dioxide and water?
30
Which carrier in the electron-transport chain is a protein (as opposed to a small molecule)?
Cytochrome c
what is a component of the etc?
FADH2
iron sulphur proteins
cytochrome c1
NADH
What does NOT participate in, nor is a component of, the electron-transport chain?
ATP
What does not pump protons?
Complex II
Which electron carrier is not able to transfer one electron at a time?
NADH
what is the pmf generated by?
the etc in mitochondria
what does the pmf do?
drives ATP synthesis in the mitochondria
what are the components of the pmf?
charge gradient of protons
chemical gradient of protons
What is not true of the proton motive force (pmf)?
Generation of the pmf in mitochondria requires succinate.
What is the ultimate electron acceptor in aerobic organisms?
oxygen
what are the features of the chemiosmotic theory?
- Electron transfer in mitochondria is accompanied by an asymmetric release of protons on one side of the inner mitochondrial membrane.
- Energy is conserved as a transmembrane pH gradient.
- Oxidative phosphorylation cannot occur in membrane-free preparations.
what is not a feature of the chemiosmotic theory?
The membrane ATPase, which plays an important role in other hypotheses for energy coupling, has no significant role in the chemiosmotic theory
The energy for ATP synthesis is generated by the movement of protons from the __________ side of the inner mitochondrial membrane establishing a(an) __________ gradient.
matrix; pH
