Oxidative Phosphorylation and Cellular Respiration

Flashcards covering key concepts of oxidative phosphorylation, cellular respiration, biochemistry of mitochondria, and related metabolic pathways.

What are the key components of oxidative phosphorylation?

The electron transport chain, ATP synthesis, and the proton gradient across the inner mitochondrial membrane.

What are NADH and FADH2 in the context of cellular respiration?

They are electron carriers that donate high-energy electrons to the electron transport chain.

What is the ultimate electron acceptor in oxidative phosphorylation?

Molecular oxygen (O2).

What is the main function of the proton gradient generated during oxidative phosphorylation?

It is used to power ATP synthesis.

How many high-energy electrons does FADH2 provide compared to NADH?

FADH2 pumps fewer protons than NADH and enters the electron transport chain at Complex II.

What happens to electrons in Complex IV of the electron transport chain?

They reduce molecular oxygen to water.

What are reactive oxygen species (ROS)?

Free radicals generated during incomplete reduction of oxygen; they can damage cellular biomolecules.

What processes do chemoautotrophs utilize for energy?

They obtain energy from chemical reactions involving inorganic compounds.

Describe the role of complex I in the electron transport chain.

Complex I (NADH-Q oxidoreductase) receives electrons from NADH and pumps protons to create a gradient.

What is produced during the citric acid cycle?

NADH, FADH2, ATP (or GTP), and carbon dioxide.

What physiological condition does a 'dead zone' refer to?

An area in water where oxygen concentration is too low for aquatic life, often due to nutrient runoff.

What occurs during the process of oxidative phosphorylation to generate ATP?

Protons are pumped across the membrane, creating a gradient that drives ATP synthesis.

What is the primary reaction that occurs in complex II?

It oxidizes succinate to fumarate and reduces FAD to FADH2 to pass electrons to ubiquinone.

How do organisms utilize anaerobic respiration?

They use final electron acceptors other than oxygen to produce ATP.

What is the significance of the Q cycle in the electron transport chain?

It couples the transfer of electrons from ubiquinol to cytochrome c and pumps protons.

What is the role of superoxide dismutase in cells?

It converts superoxide radicals into hydrogen peroxide, helping to protect cells from oxidative damage.