Oxidative Phosphorylation Overview

A process where cells use free energy stored in nutrients to create ATP (adenosine triphosphate), the primary energy currency of cells.

A process where cells use energy from ATP to build complex molecules, like proteins and carbohydrates.

The transfer of electrons from one molecule to another. Oxidation is the loss of electrons, and reduction is the gain of electrons.

Enzymes that catalyze reactions involving the transfer of electrons and hydrogen atoms, without directly using molecular oxygen.

A state where tissues are not receiving enough oxygen to function properly, leading to impaired cellular processes.

Enzymes that catalyze the oxidation-reduction reactions in biological systems. These enzymes transfer electrons from one molecule to another.

Molecules that carry electrons within the electron transport chain, facilitating the transfer of energy.

A series of protein complexes embedded in the inner mitochondrial membrane. Electrons are passed from one complex to another, releasing energy along the way.

The process by which the energy released from electron transport is used to create ATP by phosphorylation of ADP.

The theory explaining how the energy from electron transport is used to drive ATP synthesis. It involves the pumping of protons across the mitochondrial membrane, creating an electrochemical gradient that drives ATP production.

The synthesis of ATP from ADP and inorganic phosphate (Pi). This process is essential for providing energy for cellular activities.

Reduced cofactors, like NADH and FADH2, that carry electrons from the breakdown of fuels to the electron transport chain.

Cytochromes are a group of heme-containing proteins that are involved in electron transport in living organisms. They are often involved in redox reactions where an electron is transferred from one molecule to another.

Mitochondrial complexes are groups of proteins that work together in the mitochondria to carry out electron transport and ATP synthesis.

The electron-transport chain is a series of protein complexes embedded in the inner mitochondrial membrane. It is responsible for generating the majority of the ATP in eukaryotic cells.

The process of generating ATP through the movement of protons across a membrane. It requires a proton gradient, a membrane impermeable to ions, and proteins that couple electron flow with proton movement.

Complex I is the first protein complex in the ETC, responsible for transferring electrons from NADH to Coenzyme Q (CoQ).

The outermost layer of a mitochondrion, relatively porous and allowing passage of metabolites.

Complex II is the second protein complex in the ETC. It directly transfers electrons from succinate to CoQ, playing a role in the tricarboxylic acid (TCA) cycle.

Complex III is the third protein complex in the ETC. It plays a central role in the transfer of electrons from reduced CoQ (QH2) to cytochrome c.

The space between the outer and inner membranes of a mitochondrion, similar to the cytosol but with a higher proton concentration.

Complex IV is the last protein complex in the ETC. It is responsible for transferring electrons from cytochrome c to oxygen, generating water as a byproduct.

The inner layer of a mitochondrion, relatively impermeable, containing the electron transport chain and forming folds called cristae.

The central compartment of a mitochondrion, where the citric acid cycle and other metabolic processes occur, with a lower proton concentration.

Different forms of energy including mechanical, light, sound, heat, electrical and chemical energy.

The study of energy transformations and how energy is used in living organisms.

A protein that controls the production of energy molecules (ATP) during times of low oxygen. IF1 stops the cell from breaking down existing ATP. It only binds to the enzyme (ATP synthase) when the pH is low.

A protein involved in the breakdown of ATP during hypoxia. It works in the opposite direction of ATP Synthase, using ATP to pump protons across the membrane.

Rotenone, amytal, antimycin A, and cyanide are compounds that inhibit electron transport by blocking the flow of electrons along the electron transport chain, ultimately impacting oxygen consumption.

The energy currency of the cell, used to fuel many cellular processes. This is what the cell uses to power life.

When the electron transport chain is blocked by inhibitors, the electron carriers before the blockage site become reduced (gain electrons), while those after the blockage site remain oxidized (lose electrons).

Feedback inhibition is a regulatory mechanism where the product of a metabolic pathway inhibits an enzyme earlier in the pathway. In glycolysis, the high level of ATP inhibits PFK-1, slowing down glucose breakdown.

PFK-1 is a key regulatory enzyme in glycolysis. Its activity is influenced by several factors, including ATP levels and the presence of allosteric effectors.

The space between the inner and outer mitochondrial membranes. This compartment plays an important role in oxidative phosphorylation, as it provides the space for the proton gradient.

The electron transport chain is a series of protein complexes embedded in the inner mitochondrial membrane, playing a crucial role in oxidative phosphorylation. It accepts electrons from NADH and FADH2 and facilitates ATP production.