Where is the hydrogen ion concentration highest in the mitochondria?
intermembrane space
The H+ concentration is highest in the intermembrane space of the mitochondria.
What happens to the H+ ion concentration in a mitochondrion?
Inside the matrix of the mitochondria. What happens to hydrogen ions (protons) during the electron transport chain? The high concentration of hydrogen ions in the intermembrane space is used to power ATP synthase as these hydrogen ions are allowed to flow back through a channel in ATP synthase.
How many H+ are pumped into the intermembrane space?
4 H+ ions
During the reduction of oxygen, two H+ ions are extracted from the matrix and transferred to the reduced oxygen atom, thus forming water (H2O). Simultaneously, the complex pumps 4 H+ ions into the intermembrane space.
What happens as the H+ ions enter the mitochondrial matrix?
Hydrogen ions in the matrix space can only pass through the inner mitochondrial membrane through a membrane protein called ATP synthase. As protons move through ATP synthase, ADP is turned into ATP. The production of ATP using the process of chemiosmosis in mitochondria is called oxidative phosphorylation.
Do you need high concentration of hydrogen ions in the mitochondrial matrix?
i.e. For ATP synthesis to occur there is no requirement for a high steady-state concentration of hydrogen ions in the mitochondrial matrix — quite the opposite (as is reflected by the pH 8). A relatively high concentration of hydrogen ions is only required in the inter-membrane space — as is indeed found.
Why is H + concentration low in the mitochondria?
The H + concentration is kept low in the matrix and high in the inter-membrane space, even though protons are continually flowing into the matrix. i.e. For ATP synthesis to occur there is no requirement for a high steady-state concentration of hydrogen ions in the mitochondrial matrix — quite the opposite (as is reflected by the pH 8).
When does mitochondrial NADH + H + arrive at etc?
Mitochondrial NADH+H+ arrives directly at the ETC from the TCA cycle and immediately oxidizes to NAD+, with its protons (hydrogen ions) remaining in the matrix, and its electrons (e-) going to complex I. As the electrons arrive on complex I, the complex immediately goes through a series of redox (reduction and oxidation) reactions.
Where do electrons go in the mitochondria complex?
As electrons move through complex III, more hydrogen ions are pumped across the membrane, and the electrons are ultimately delivered to another mobile carrier called cytochrome C (cyt C). Cyt C carries the electrons to complex IV, where a final batch of hydrogen ions is pumped across the membrane.
