Mitochondria and chloroplasts Flashcards
anabolic reaction
energy requiring
catabolic reaction
energy yielding
F0 component of ATP synthase
integral membrane
Forms a channel that allows protons (H⁺) to pass through the membrane. This component harnesses the energy from the proton gradient to drive the rotational motion necessary for ATP synthesis
F1 component of ATP synthase
peripheral, on cytoplasmic side of membrane
catalytic sites for ADP+Pi–>ATP
mechanism of ATP production by ATP synthase in terms of energy transfers
proton gradient = stored energy
as protons floe through F0, energy converted to mechanical energy to move the stalk, which mechanically deforms the F1 subunits (alpha and beta). this conformational energy is converted to chemical bond energy
components of proton gradient
membrane potential (difference in voltage)
difference in proton concentration (change in pH)
conformational changes ATP synthase
initial conformation accepts an electron and a proton. neutralisation causes conformational change=proton facing other side of membrane. release of proton=revert to original conformation
3 complexes in mitochondrial inner membrane that pump protons
NADH dehydrogenase
cytochrome bc1 complex
cytochrome oxidase complex
cytochrome oxidase complex
stores oxygen that combines with the electrons to form water
what do mobile electron carriers do
transfer electrons between proton pumping complexes
ubiquinone
lipid-like
carries electrons from NADH dehydrogenase to the cytochrome bc1 complex
cytochrome c
carries electrons from cytochrome bc1 complex to cytochrome oxidase complex
direction of proton transfer for mitochondria
protons are pumped into intermembrane space from matrix via the pumps
establishes proton gradient
protons pass to the matrix via ATP synthase
high electron transfer potential
donates electrons
-ve
strong reducing agent
eg NADH
why is H2O a poor electron donor
low electron transfer potential
+ve
