Stage 4 The Electron Transport Chain Flashcards
where do the hydrogen atoms derived from NADH and FADH2 go?
they carry a series of compounds or proteins associated with the inner mitochondrial matrix
what are the components of the ETC arranged in order of
increasing electronegativity
how is free energy used in the electron transport chain?
the free energy released from electrons after redox reactions because they are in a more stable position are used to build an electrochemical gradient of H+ ions
what is the function of transport proteins?
pump ions from the mitochondrial matrix to the intermembrane space
what is an example of a redox reaction in the electron transport chain?
NADH and FADHS deposit their electrons to the protein components of the electron transport chain. NADH and FADH2 are oxidized meaning they lose electrons while the proteins of the electrons transport chain are reduced or they gain electrons
why are electrons proportional to H+ ions
the more electrons transferred the greater number of H+ ions that can be pumped to accumulate in the intermembrane space
how is the proton motive force formed?
after the chemical potential energy of the electrons is converted to electrochemical potential energy, it forms a protein gradient across the inner mitochondrial membrane
why is it both an electrical and concentration gradient?
it is a concentration because there are more H+ions in the intermembrane space than in the matrix. The term electrical is used because hydrogen atoms carry a positive charge and there are more positive charges in the intermembrane space than in the matrix
how are chemiosmosis atoms similar to osmosis?
hydrogen atoms move passively flow down the concentration gradient moving from the intermembrane space back into the mitochondrial matrix. it is similar to osmosis as the passive movement of molecules to restore equilibrium however it is hydrogen atoms rather than water hence the term chemiosmosis
why use energy to pump hydrogen atoms to the intermembrane space only to pump it all back?
the hydrogen moves back in through specific channels provided by ATP synthase. ATP synthase needs the downhill current created by ATP synthase created by hydrogen atoms to attach ADP and phosphate. for every hydrogen atom pumped, 1 ATP is formed
why is the method of ATP formation called Oxidative Phosphorylation?
the electron transport chain will only continue to shuttle electrons if oxygen is present as the last electron acceptor
how is the problem of the 2NADH produced from glycolysis into the cytoplasm not passing the inner mitochondrial membrane and getting stuck in the intermembrane space fixed?
the glycerol phosphate shuttles take the electrons from the NADH from glycolysis and give them to FAD to produce FADH2, which can pass across the intermembrane space
how many hydrogen atoms does FADH2 produce after being made from the glycerol phosphate shuttle and why?
because FADH2 enters the electron transport chain at Q-ubiquinone it only pumps 2 hydrogens per pair of electrons and therefore only produces 2 ATP rather than 3
