1. Chapter 7: Cellular Respiration

2. Cellular Respiration
Process where cells make ATP by breaking down glucose
Autotrophs and heterotrophs both undergo respiration
Occurs in the cytoplasm and mitochondria

3. Cellular Respiration Overall equation:
C6H12O6 + 6O2  6CO2 + 6 H2O + ATP
How is this equation different from photosynthesis?

4. What’s so great about ATP?
Every time you move a muscle, think, breathe, replicate your DNA, every time your heart beats - you use ATP to do this work!

5. Mitochondria Parts Matrix: Fluid
Inner membrane: folded membrane inside mitochondria
Cristae: inner folds of innermembrane
Intermembrane space: space between outer and innermembrane

6. Two pathways exist for accessing stored energy…
Aerobic Pathways take place in the presence of oxygen
Anaerobic Pathways take place in the absence of oxygen
Both pathways: 1) Begin with Glycolysis
2) Produce a Pyruvic Acid Intermediate
3) Differ in ATP production and final product

8. Step 1: Glycolysis
6-carbon glucose molecule is broken down into two 3-carbon pyruvic acid molecules.
Location: cytoplasm
Reactant: glucose
Products: pyruvic acid and 2 ATPs
Anaerobic: does not require oxygen

9. If oxygen is present then Aerobic respiration occurs
If oxygen is not available then cells continue to perform glycolysis to make 2 ATPs

11. Step 2: Kreb’s Cycle Krebs Cycle: Reactants: Products:
Series of reactions that occur in mitochondrial matrix
Reactants:
Pyruvic acid
(from glycolysis)
Products:
2 CO2
2 ATP
NADH (e- carrier)

12. Step 3: Electron Transport Chain and Chemiosmosis
The “big ATP payoff”
Location: cristae (inner membrane) of mitochondria
Reactants: NADH, O2
Products: NAD+, H2O, 34 ATP

13. Step 3: Electron Transport Chain and Chemiosmosis
NADH transfers e- to the Electron transport chain
(e- move down a series of proteins)
Figure 4.22

14. Step 3: Electron Transport Chain and Chemiosmosis
NADH transfers e- to the Electron transport chain
(e- move down a series of proteins)
At the end of the chain, the electrons combine with oxygen & H+ to produce H2O.
Figure 4.22

15. Step 3: Electron Transport Chain and Chemiosmosis
Energy from the e- pulls H+ into the intermembrane space.
Figure 4.22

16. Step 3: Electron Transport Chain and Chemiosmosis
H+ move from HIGH conc. to LOW conc.
They diffuse through ATP synthase, generating 34 ATPs (chemiosmosis)
Outer mitochondrial membrane
Inner mitochondrial membrane
Electron transport chain proteins
NADH 26
1/2 O2 + 2H+
H2O H+
Cytosol
Intermembrane space 2
ADP + P
ATP

17. Total Energy Production: 36 ATP
2 ATP from glycolysis
2 ATP from Kreb’s Cycle
34 ATP from ETC (chemiosmosis)
38 ATP Made In Total
- 2 ATP for transporting pyruvic acid into the Mitochondria from Glycolysis
36 Net ATP Made
Aerobic Respiration is 20 times more efficient than Glycolysis alone.

18. Anaerobic vs. Aerobic
Anaerobic pathway (fermentation): Glycolysis  2 ATP

19. Anaerobic vs. Aerobic
Anaerobic pathway (fermentation): Glycolysis  2 ATP
Aerobic Pathway:
Glycolysis + Kreb’s Cycle + ETC  36 ATP

20. Make and fill in this chart
Process
Location
Reactants
Products
# of ATP Made
Glycolysis
Kreb’s Cycle
Electron Transport Chain

21. Movies: , &

22. Fact
Fact: Our bodies uses ATP at the rate of about 1 million molecules per cell per second.
There are more than 100 trillion cells in the human body. That’s about 100,000,000,000,000,000,000 ATP molecules used in your body each second!

23. What is the relationship between autotrophs and heterotrophs?