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NADH and FADH2 in the electron transport chain do not directly donate electrons to oxygenWhy?
Wiki User
∙ 14y ago
The temperature in cells is not high enough. Each of the redox reactions in the electron transport chain are catalyzed by an enzyme. NADH dehydrogenase transfers electrons from NADH to ubiquinone, and cytochrome c oxidase transfers electrons from cytochrome c to oxygen. So there is no enzyme to pass the electrons directly from NADH to oxygen.
Wiki User
∙ 14y ago
Wiki User
∙ 14y agoBecause that's the whole point of the ETC. NADH donates electron through three intermediates, generating 1 ATP per intermediate until it finally reaches O2. FADH2 only goes through ubiquinone or carrier Q before giving it to oxygen and thus creates 1 drop per electron with 2 electrons resulting in 2 ATP. If they donated directly to oxygen, they would bypass all these intermediates, thus bypassing the part where ATP is made, therefore yielding no ATP and defeating the purpose of the ETC. If your question is physically why oxygen is unable to just take it from NADH and FADH2, then I would say that it is because oxygen is never allowed to come into contact with anything other than the doners that are meant to give it to oxygen. It is probably physically separated in the mitochondrial membrane.
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What happens to electrons when pigments in photosystem II absorbs light?
they move through an electron transport chain to photosystem 1
What event contributes directly to the creation of a proton gradient across the thylakoid membrane?
the flow of electrons through electron transport chain II
Where are the proteins of electron transport chains located?
where are the proteins of the electrons transport chain located
Why is oxygen needed for the final step in cellular respiration?
Oxygen is the final electron acceptor. Oxygen, with it's great electronegativity, pulls electrons through the electron transport chain where these electrons provide the motive force to pump protons into the outer lumen of the mitochondria. When these protons fall down their concentration gradient oxygen is there to pick then up with the electrons and form water.
After electrons leave photosystem II they go into an electron transport chain of three protein complexes Where do they go after that electron transport chain?
They go into photosystem I.
The electron transport chain receives electrons directly from?
NADH
Series of electron acceptors in the thylakoid membrane that removes energy from excited electrons to produce ATP?
Electron transport chain.
Transport chain series of proteins embedded in a membrane along which energized electrons are transported as electrons are passed from molecule energy is released?
Transport chain series of proteins embedded in a membrane along which energized electrons are transported as electrons are passed from molecule energy is released?
How many electrons can a NADH molecule carry?
The electron transport chain is also known as the respiratory chain. NADH carries electrons in the form of hydrogen atoms to the electron transport chain.
Do the energized electrons at the primary electron acceptor flow to the reaction center?
No, the electrons flow from the reaction center to the primary electron center. Just the opposite of what you said.
What does the electron transport chain use the high energy electrons for the Krebs cycle for?
The electrons are passed down the electron transport chain for use in ATP production.
High-energy electrons from NADH and FADH2 are passed into and along the?
Electron Transport Chain
Energized electrons at the primary electron acceptor flow to where?
an electron transport chain.
Where does the electron transport chain get its electrons from?
it gets electrons[2 eletrons from NADH and 2 electrons from FADH2] from NADH and FADH2....In case of NADH- it is directly from glycolysis but in case of FADH2-it is not directly attached to ETC but succinate is oxidised to fumarate realising FADH2
What uses energy from the high-energy electrons to transport hydrogen across the thylakoid membrane?
Electron transport chain
Where does the electron transport chain get high energy electrons that are passed down the chains?
High-energy electrons from NADH and FADH2 are passed along the electron transport chain
What does the electron transport train produce?
The electron transport chain is used to make ATP.
