1. Cellular Respiration

2. Cellular Respiration

3. “The Powerhouse”
Image from:

4. Aerobic Cellular Respiration
extracts energy from food in the presence of oxygen
energy is used to synthesize ATP from ADP and Pi
eukaryotes & prokaryotes that are obligate aerobes undergo Cellular respiration

5. Image from: http://factfictionfancy. wordpress

6. Aerobic Cellular Respiration
4 stages:
Glycolysis
Pyruvate oxidation (Transition stage)
Citric acid cycle
Electron transport Chain & oxidative phosphorylation

7. 6 Carbons Glucose sugar
Electron
Transport Chain
32 ATP
6O2
6H2O C
Pyruvate
oxidation
CO2 2
Citric Acid Cycle
2 ATP
CO2 C 4 C
2 ATP
Glycolysis C

8. 1. Glycolysis takes place in cytoplasm
enzymes break down one molecule of glucose into two molecules of pyruvate
some ATP and NADH are produced

9. 2. Pyruvate Oxidation (transition stage)
occurs in the mitochondria
pyruvate is transported (via carrier protein) into mitochondria and is oxidized, forming acetyl-CoA
CO2 and NADH are produced

10. 3. Citric Acid (Krebs) Cycle
takes place in mitochondria
acetyl-CoA enters a cycle and is completely oxidized to CO2
ATP, NADH and FADH2 are produced

11. 4. Electron Transport… takes place in mitochondria
the NADH and FADH2 from the first 3 stages are oxidized
H2O and a large amount of ATP is produced (32-34)

12. ATP can be produced in two ways:
1. Substrate-level phosphorylation
- catalyzed by a kinase
- phosphate is transferred directly from a substrate
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13. 2. Oxidative phosphorylation catalyzed by ATP synthase
process uses energy transferred indirectly from a series of redox reactions
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14. What if there is no O2?
many organisms can extract energy from food without using oxygen using anaerobic respiration and fermentation
much lower amount of energy release in anaerobic pathways

15. Anaerobic Respiration
We know what obligate aerobes are…
What about…
obligate anaerobes?
facultative anaerobes?
Obligate anaerobes - bacteria that cause botulism, tetanus, protist Trichonympha
Facultative anaerobes - yeast, E. coli bacteria that live in our gut

16. Classwork/Homework
Read 4.1
1-7 pg 171
Review notes 20