Mitochondrial Energy Conversion and Chemiosmotic Coupling

This set of flashcards covers mitochondrial structure, the electron-transport chain, oxidative phosphorylation, and the metabolic processes of the citric acid cycle based on the provided lecture notes.

The link between bond-forming reactions and membrane transport processes in the mitochondria is called __________.

chemiosmotic coupling

The energy released by the electron transfers between protein complexes in the electron-transport chain is used to drive the movement of __________ to one side of the membrane.

protons

During metabolism, food molecules are ultimately converted into __________, which then enters the citric acid cycle.

acetyl CoA

Electrons removed during the oxidation of acetyl groups in the citric acid cycle are captured by the activated carriers __________ and __________.

NADH; FADH2

The production of ATP in the cytosol during glycolysis, which occurs in the absence of oxygen, is known as __________ phosphorylation.

substrate-level

During oxidative phosphorylation, a phosphate group is added to __________ to produce ATP.

ADP

The citric acid cycle stops immediately when $O_2$ is removed because it requires the oxidized forms of __________ and __________.

NAD+; FAD

The __________ mitochondrial membrane contains porins, allowing passage of molecules with a mass less than $5000\,\text{daltons}$.

outer

The inner mitochondrial membrane is a single, highly convoluted membrane that forms discrete-looking sections called __________.

cristae

The __________ is the compartment that contains the mitochondrial genome and the enzymes for the citric acid cycle.

mitochondrial matrix

Proteins of the electron-transport chain, ATP synthase, and transport proteins for pyruvate are all located in the __________ membrane.

inner mitochondrial

The __________ of the mitochondria is chemically equivalent to the cytosol with respect to pH and small molecules.

intermembrane space

Mitochondrial division is mechanistically similar to __________ cell division.

prokaryotic

Specific proteins that are released during the process of __________ are located within the mitochondrial intermembrane space.

apoptosis

The mitochondrial matrix contains enzymes required for the oxidation of __________.

fatty acids

When the high-energy bond in NADH is cleaved, it donates a pair of electrons and produces $NAD^+$ and a(n) __________.

hydride ion ($H^-$)

Mitochondria can use both __________ and __________ directly as fuel.

pyruvate; fatty acids

In the electron-transport chain, __________ acts as the final electron acceptor.

oxygen ($O_2$)

The movement of electrons along the electron-transport chain is coupled to the pumping of protons into the __________.

intermembrane space

The final result of electron transfers in the electron-transport chain is that $O_2$ is reduced to __________.

$$H_2O$$

In chemiosmosis, energy is harnessed from the movement of protons __________ a concentration gradient into the matrix.

down

Internal to the electron-transport chain, the component __________ does not act as a proton pump.

cytochrome c

NADH donates its electrons to __________, which is the first of the three respiratory enzyme complexes.

NADH dehydrogenase

The first mobile electron carrier in the respiratory chain is __________, and the second is __________.

ubiquinone; cytochrome c

The respiratory enzyme complex responsible for transferring electrons to oxygen is __________.

cytochrome c oxidase

The pH in the mitochondrial matrix is __________ than the pH in the intermembrane space.

higher (more alkaline)

The total proton-motive force is driven by both the proton concentration gradient and the __________ generated by the electron-transport chain.

membrane potential