Knowing that in the end, you get 6 molecules of water from one glucose molecule. This is the overall formula for cell respiration, however, you ask how many water molecules are produced specifically during electron transport chain? When protons flow through ATP synthase, they cause it to turn (much as water turns a water wheel), and its motion catalyzes the conversion of ADP and Pi to ATP. When protons flow back down their concentration gradient (from the intermembrane space to the matrix), their only route is through ATP synthase, an enzyme embedded in the inner mitochondrial membrane. The proton gradient generated by proton pumping during the electron transport chain is a stored form of energy. Eventually, the electrons are passed to oxygen, which combines with protons to form water. The electrons flow through the electron transport chain, causing protons to be pumped from the matrix to the intermembrane space. This step regenerates NAD+ and FAD (the oxidized carriers) for use in the citric acid cycle. NADH and FADH2 made in the citric acid cycle (in the mitochondrial matrix) deposit their electrons into the electron transport chain at complexes I and II, respectively. The electron transport chain and ATP synthase are embedded in the inner mitochondrial membrane. Overview diagram of oxidative phosphorylation. Four electrons are required to reduce each molecule of O 2 _2 2 start subscript, 2, end subscript, and two water molecules are formed in the process. Complex IV passes the electrons to O 2 _2 2 start subscript, 2, end subscript, which splits into two oxygen atoms and accepts protons from the matrix to form water. Cyt C carries the electrons to complex IV, where a final batch of H + ^+ + start superscript, plus, end superscript ions is pumped across the membrane. As electrons move through complex III, more H + ^+ + start superscript, plus, end superscript ions are pumped across the membrane, and the electrons are ultimately delivered to another mobile carrier called cytochrome C ( cyt C). Both complex I and complex II pass their electrons to a small, mobile electron carrier called ubiquinone ( Q), which is reduced to form QH 2 _2 2 start subscript, 2, end subscript and travels through the membrane, delivering the electrons to complex III. Beyond the first two complexes, electrons from NADH and FADH 2 _2 2 start subscript, 2, end subscript travel exactly the same route.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |