chapter 9 Flashcards
What is the function of cellular respiration?
to break down glucose or other organic molecules to provide the energy needed to regenerate ATP.
What are the reactants and the products of cellular respiration?
the reactants are glucose and oxygen, the products are carbon dioxide, water, and energy
In what parts of the cell do the metabolic pathways of cellular respiration take place?
Glycolysis takes place in the cytosol; pyruvate oxidation, citric acid cycle, and oxidative phosphorylation take place in the mitochondria.
What are the energetic and/or product outputs of Glycolysis
2 pyruvate, 2 NADH, 2 H+ and 4 ATP
What are the energetic and/or product outputs of the Citric acid cycle
2 ATP, 6 NADH, 2 FADH2
What are the energetic and/or product outputs of Oxidative phosphorylation
about 26-28 ATP
Where does glycolysis occur?
in the cytosol
Is glycolysis aerobic?
No, it doesn’t require oxygen
What are the two phases of glycolysis?
Energy investment and energy payoff
At what phase in glycolysis is energy used?
Energy investment
What is the final product of glycolysis?
For each glucose molecule that enters glycolysis, two pyruvates are produced
Where in the cell does the citric acid cycle take place?
Inside the mitochondrion
Does substrate level phosphorylation occur in the citric acid cycle, how many times per cycle?
Yes, once per cycle
What is produced as a result of each cycle of the citric acid cycle?
1 ATP, 3NADH, 1 FADH2, 2 CO2
Where in the mitochondria does oxidative phosphorylation occur?
cross the inner membrane
What molecules carry electrons to the machinery of oxidative phosphorylation?
NADH
Is the process of oxidative phosphorylation aerobic? If so, what does oxygen have to do with the process?
Yes, it is aerobic. Oxygen serves as the final electron acceptor of the electron transport chain.
How does the availability of oxygen affect oxidative phosphorylation?
If there isn’t any oxygen then electron transport shuts down and there isn’t the chemical gradient needed to power oxidative phosphorylation. In short, it doesn’t happen
Describe chemiosmosis.
Electron transfer in the electron transport chain causes proteins to pump H+ from the mitochondrial matrix to the intermembrane space; The energy stored in a H+ gradient across a membrane couples the redox reactions of the electron transport chain to ATP synthesis; H+ then moves back across the inner membrane, passing through the proton, ATP synthase; ATP synthase uses the exergonic flow of H+ to drive phosphorylation of ATP; This is an example of chemiosmosis, the use of energy in a H+ gradient to drive cellular work
Compared to glycolysis and the citric acid cycle, how would you describe the amount of ATP that oxidative phosphorylation produces.
OP produces 90% of the ATP produced by cellular respiration
Describe fermentation.
fermentation uses anaerobic substrate-level phosphorylation instead of an electron transport chain to generate ATP
What are the reactants and the products of fermentation?
reactants are glucose and products are either 1) ethanal (alcohol) and carbon dioxide or 2) lactic acid
