Electron Transport Chain Diagram Labeled

ninja icon

Understanding:

• Transfer of electrons between carriers in the electron ship chain in the membrane of the cristae is

coupled to proton pumping

The final stage of aerobic respiration is the electron transport chain, which is located on the inner mitochondrial membrane

The inner membrane is arranged into folds (cristae), which increases the surface expanse available for the transport concatenation

The electron transport chain releases the free energy stored within the reduced hydrogen carriers in order to synthesise ATP

This is called oxidative phosphorylation, as the energy to synthesise ATP is derived from the oxidation of hydrogen carriers

Oxidative phosphorylation occurs over a number of singled-out steps:

Proton pumps create an electrochemical gradient (proton motive force)
ATP synthase uses the subsequent diffusion of protons (chemiosmosis) to synthesise ATP
Oxygen accepts electrons and protons to form h2o

Step 1: Generating a Proton Motive Force

The hydrogen carriers (NADH and FADH₂) are oxidised and release high energy electrons and protons
The electrons are transferred to the electron transport chain, which consists of several transmembrane carrier proteins
As electrons pass through the concatenation, they lose free energy – which is used by the concatenation to pump protons (H⁺ ions) from the matrix
The accumulation of H⁺ ions within the intermembrane space creates an electrochemical gradient (or a proton motive force)

ETC1

ninja icon

Understanding:

• In chemiosmosis protons lengthened through ATP synthase to generate ATP

Step Two: ATP Synthesis via Chemiosmosis

The proton motive force will crusade H⁺ ions to move downwardly their electrochemical gradient and lengthened back into matrix
This diffusion of protons is called chemiosmosis and is facilitated past the transmembrane enzyme ATP synthase
As the H⁺ ions move through ATP synthase they trigger the molecular rotation of the enzyme, synthesising ATP

ETC2

ninja icon

Agreement:

• Oxygen is needed to bind with the free protons to maintain the hydrogen gradient, resulting in the formation

of water

Step Three: Reduction of Oxygen

In guild for the electron transport concatenation to proceed functioning, the de-energised electrons must exist removed
Oxygen acts as the last electron acceptor, removing the de-energised electrons to prevent the chain from condign blocked
Oxygen likewise binds with free protons in the matrix to form water – removing matrix protons maintains the hydrogen slope
In the absenteeism of oxygen, hydrogen carriers cannot transfer energised electrons to the chain and ATP production is halted

ETC3

Summary: Oxidative Phosphorylation

Hydrogen carriers donate loftier energy electrons to the electron transport chain (located on the cristae)
As the electrons move through the chain they lose energy, which is transferred to the electron carriers within the chain
The electron carriers use this energy to pump hydrogen ions from the matrix and into the intermembrane infinite
The accumulation of H⁺ ions in the intermembrane space creates an electrochemical slope (or a proton motive force)
H⁺ ions return to the matrix via the transmembrane enzyme ATP synthase (this improvidence of ions is called chemiosmosis)
As the ions pass through ATP synthase they trigger a phosphorylation reaction which produces ATP (from ADP + Pi)
The de-energised electrons are removed from the concatenation past oxygen, allowing new loftier energy electrons to enter the concatenation
Oxygen likewise binds matrix protons to form water – this maintains the hydrogen gradient by removing H⁺ ions from the matrix