1. Cellular Respiration

2. C6H12O6 + 6O2 → 6CO2 + 6H2O + Energy (as ATP)

3. ATP ADP + P

5. Glycolysis
Phase 1

6. “glucose breaks”
Occurs in cytoplasm
Energy Investment Phase.

7. PHOSPHORYLATION –
ATP invested for
activation. (This
destabilizes the glucose
molecule slightly.)
Destabilized
form of glucose.

8. Destabilized
form of glucose.
Rearrangement of atoms.
Fructose-6-phosphate forms.
It is an isomer of glucose-6-
phosphate.
PHOSPHORYLATION –
More ATP is invested,
resulting in Fructose 1,6
diphosphate.

9. Fructose 1,6
diphosphate is broken
down into TWO 3
carbon molecules.
Remember: There are
TWO product
molecules for this and
each succeeding step.
Net result: Two
glyceraldehyde
phosphate molecules.
C C

10. Energy Yielding Phase

11. Glyceraldehyde phosphate
is oxidized as NAD picks
up high energy electrons
and hydrogen.
2 NADH are formed.
These are high energy
molecules.

12. ATP Production

13. Phosphate transferred to
another carbon.

14. Water produced.
ATP produced. 2
pyruvate molecules
result.
Depending on the organism,
and oxygen conditions, the 2
pyruvate molecules go through
one of the following: alcohol
fermentation, lactic acid
fermentation (both anaerobic
respiration) or aerobic
respiration.

15. Summary of Glycolysis
Starts with:
1 glucose molecule (C6H12O6)
2 ATP
Ends with:
2 pyruvate molecules
2 NADH
4 ATP (Gross), 2 ATP (NET)
2 H2O
This process stores a small amount of
energy in the bonds of ATP. Where
did the energy come from?
Bond energy in GLUCOSE!

16. ATP production
4 ATP generated
- 2 ATP invested
2 ATP net

17. The Fate of Pyruvate
Phase 2

18. Depending on the type of
organism, and / or oxygen
conditions, pyruvate will be
broken down via one of the
following pathways.

19. Anaerobic Pathways

20. Occurs if oxygen is ABSENT.

21. Pyruvate
Occurs in yeast and some bacteria.
NET ATP production: 2 ATP (from glycolysis)
NADH from glycolysis is recycled so that NAD
can be reused in glycolysis.

22. Occurs in muscles during power
activities such as powerlifting and
sprinting.
NET ATP production: 2 (from glycolysis)
CONSIDER THIS: WHY DO HUMANS NOT PRODUCE
ALCHOHOL IN THEIR MUSCLES WHEN OXYGEN IS ABSENT?

23. Transition Reactions and Krebs Cycle

24. If oxygen is present

26. REMEMBER: There are
TWO pyruvate molecules * NADH carries enough
from the original glucose energy to make 3 ATP
molecule. Everything you molecules in the electron
see on this page happens transport chain.
TWICE.
TRANSITION REACTIONS:
1. Pyruvate is transported into mitochondria by a carrier molecule.
2. Require a “multienzyme complex” which
1. Removes CO2
2. NAD accepts hydrogen and high energy electrons. NADH forms.*
3. CoA joins acetyl group to make it active.

27. 2C
6C
4C
Acetyl CoA reacts with oxaloacetate (4C) to produce citrate (6C).

28. 6C
Citrate is isomerized to
isocitrate.
6C

29. Isocitrate loses CO2.
6C NAD picks up hydrogen, electrons
and energy from isocitrate.
Which has more
energy:
isocitrate or
ketoglutarate. . .
5C

30. 1. CO2 is removed.
5C
2. NADH forms.
3. CoA is bonded with a
high energy bond.
4C

31. 4C 4C
ATP forms.

32. 4C FADH2 forms.
Every FADH2 molecule is used
to produce 2 ATP molecules in
the electron transport chain.
4C

33. 4C
4C

34. 4C
Another NADH molecule
forms and oxaloacetate
reforms.
4C

35. The cycle begins again . . .
2C
6C
4C

36. Summary of Transition Reactions and Krebs
Cycle
Each pyruvate molecule entering the
mitochondria goes through the
transition reactions and Krebs cycle
and results in:
2 CO2
4 NADH
1 FADH2
1 ATP
From one glucose molecule:
2 CO2 X 2 = 4 CO2
4 NADH X 2 = 8 NADH
1 FADH2 X 2 = 2 FADH2
1 ATP X 2 = 2 ATP

37. The Electron Transport Chain
Phase 3

38. NADH and FADH2 transfer their electrons to carriers in the inner membrane of
the mitochondria. Each NADH generates 3 ATP. Each FADH2 generates 2 ATP.
http://www.youtube.com/watch?v=nXop37NVOAY&feature=related

39. For every NADH that enters the
chain, 3 ATP are formed.
For every FADH2 that enters the
chain, 2 ATP are formed.
FADH2
FAD
Water is the final electron acceptor.
The electrons, hydrogen and oxygen
combine to form one water molecule.

40. Where is all the ATP
generated?

41. x3
x3
x2
x3
x2 x3
x3 x3
x2

42. Glycolysis
- 2 ATP
+ 4 ATP
2 NADH x 3 = + 6 ATP
Transition Reactions and Krebs Cycle
-2 ATP*
+2 ATP
8 NADH x 3 = +24 ATP
2 FADH2 x 2 = +4 ATP
36 ATP