Cellular Respiration Flashcards
How are metabolic pathways regulated?
- “End product Inhibition”- they are regulated by their product- stops overproduction
A sigmoid curve is a representation of what type of inhibition?
A sigmoid curve is representation of cooperative allostery
What happens to C-O bonds and C-H bonds when burning glucose?
When burning glucose, C-O bonds increase, C-H bonds decrease
In what form is oxidation energy stored?
NAD- reduced to NADH
How does NAD create energy? What happens when it is coupled with oxygen?
NADH is oxidized it releases energy
When NADH is coupled with oxygen, electrons flow away from NADH
When coupled with oxidation of glucose, e- flow toward NAD+
What is the best electron acceptor?
Oxygen!
Formula for NAD+ reduction
NAD+ + H+ + 2e- NADH
What is redox potential?
The tendency to lose or gain electrons
List the 4 steps of cellular respiration
1) Glycolysis
2) Pyruvate Processing
3) Citric Acid Cycle
4) Electron Transport and Chemiosmosis
What are start and end products of glycolysis?
- ATP is used to split C6 into 2C3 (pyruvate) in cytosol
What happens during pyruvate processing?
Pyruvate is oxidized to create acetyl coA. Biproducts are NADH, H+, ATP
This happens in the mitochondria
What are products of citric acid cycle- what catalyzes this reaction?
- Acetyl coA gives 2CO2, FADH, NADH
- catalyzed by dehydrogenases
What is step in cell resp that isn’t a redox reaction?
Only step that isn’t redox is GTP
Electron Transport Chain
A series of redox reactions coupled to transport of protons across inner mitochondria membrane
- Required to get rid of NADH because cells need more ATP than NADH they need NAD+ for citric acid to continue
-
What carries electrons through ETC?
Ubiquinone
Which complex of the ETC in cellular respiration releases the most H+?
Complex 3
After the ETC, what is the next step?
The next step is using the transported electron and the gradient set up by ETC to use ATP synthase
High _____ shuts down glycolysis, citric acid cycle, and ETC (different for each one)
High ATP shuts down glycolysis
High NADH shuts down citric acid cycle
High Proton gradient shuts down ETC
In anaerobic respiration, what happens?
Just glycolysis
Pyruvate is used as the main electron acceptor, to replenish NAD+.
What is chemiosmosis?
Protons travel down electrochemical gradient through ATP synthase to create ATP
Two types of fermentation
- Alcoholic- glycolysis gives H+ to acetaldehyde, creating ethanol
- Lactic Acid- glycolysis gives H+ to pyruvate yielding lactate as a biproduct
Is ATP synthase endergonic or exergonic?
Exergonic!
