NADH is the electron donor for the
electron transport chain. The first complex to accept the donated
electrons is NADH dehydrogenase. Clicking on each of the
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The electron transport chain
is embedded in the inner membrane of the mitochondria. It
consists of four large protein complexes, and two smaller
mobile carrier proteins.
NADH is the electron donor in this system.
It initiates the electron transport chain by donating electrons
to NADH dehydrogenase (blue).
NADH donates two electrons to NADH dehydrogenase.
At the same time, the complex also pumps two protons from
the matrix space of the mitochondria into the intermembrane
The two electrons are now transferred
to the mobile carrier protein known as ubiquinone. Ubiquinone
transports the electrons, two at a time, to the next complex
in the chain.