Citric acid cycle/ETC Flashcards
Citric acid cycle
- There to finish oxidation of glucose, by converting acteyl-coA to C02. Then the result after is FADH and NADH. (only step that is not ready for redox reaction)
ETC
- required to get rid of all the NADH. Cell needs more ATP and needs NAD+ for citric acid cycle to continue. Series of redox reactions
Why does NADH deliver its electrons directly to 02?
- reaction needs to be catalyzed
- NADH can only bind to first enzyme complex of electron transport chain - gradual release of energy
Are the intermediate stages of citric acid cycle reactive?
Yes! All of them are highly reactions radicals with free electrons.
Cyanide
- shuts down ETC
Oxidative phosphorylation
- protons flow through Chanel ATP synthase and make ATP.
- The formation of ATP is a chemiosmotic mechanism.
What is the proof that ATP synthase and ETC function independently?
- vesicles containing ATP synthase was made, increase [proton] outside vesicle, protons flow inward through ATP synthase, ATP production on inside
- ATP synthase is older, use to not have ETC, can also function in reverse (via ATP hydrolysis)
How is glycosis, citric acid cycle, and ETC regulated?
- glycolysis shut down by high [ATP]
- citric acid cycle by high [NADH]
- ETC by high proton gradient
What happens to ETC and citric acid cycle if there is no oxygen?
- ETC shuts down, pyruvate oxidation and citric acid cycle can no longer operate, they need NAD+ which comes from ETC
Under anoxic conditions, what is the only thing that can provide energy?
Fermentation
Fermentation
- step backward
- does not generate energy, just replenishes NAD+ that was used up in glycolysis
Why does oxidation of fats take longer than carbohydrates or proteins?
- there are more C-H bonds in fats so it takes longer to complete, giving more NADH
