Stored in food due to the arrangement of the electrons in the bonds
Potential Energy
2 main pathways for cellular respiration
Aerobic
Anaerobic (fermentation)
Cellular respiration is:
Exergonic/endergonic
Anabolic/catabolic
ΔG>/<0
Exergonic, catabolic, ΔG<0
Loss of electrons
Oxidation
Gain electrons
Reduction
Stages of cellular respiration
- glycolysis
- Pyruvate oxidation and the citric acid cycle
- Oxidation phosphorylation
Why isn’t glucose oxidized all at once?
Too much energy would be lost
Glycolysis takes place in
Cytosol
Glycolysis splits glucose into 2 molecules of
Pyruvate
Glycolysis has a net yield of ___ ATP
2
Pyruvate enters the mitochondria through
Active transport
3 rxns take place with pyruvate oxidation
- COO- removed and given off as CO2
- Remaining 2-Carbon molecule is oxidized (NADH formed)
- Coenzyme A added to form acetyl CoA (high potential energy)
Series of 8 steps, each catalyze by enzyme
-redox rxns
Citric acid cycle
Citric acid cycle occurs in
Mitochondria matrix
1 cycle of citric acid cycle produces:
2 CO2
1 GTP (ATP)
1 NADH
1 FADH2
Per glycolysis molecule…
-glycolysis + 2 ATP
-Krebs Cycle + 2 ATP
____________
Total = Net + 4 ATP
2 steps to oxidative phosphorylation
- electron transport chain
- chemiosis
(Where majority of ATP is produced)
Collection of molecules embedded in mitochondrial inner membrane
ETC
Final electron acceptor is
Oxygen
Exergonic flow of electrons is used to pump H+ across membrane
Chemiosis
Energy-coupling mechanism that uses energy stored stored in a H+ gradient to drive cellular work
Chemiosis
Uses energy of H+ gradient to power
ATP synthesis
H+ ions flow through ATP synthase up/down conc. Gradient
Down
Still uses ETC but O2 is not the final e- acceptor
Anaerobic respiration
