2. Photosynthesis & Cellular Respiration

3. The opposite of photosynthesis!!
Photosynthesis makes glucose
Cellular Respiration breaks glucose into ATP

4. Cellular Respiration takes place in the mitochondria

5. 3 steps for Cellular Respiration
1) Glycolysis
2) Krebs Cycle (Citric Acid Cycle)
3) Electron Transport Chain (ETC)

6. 1) Glycolysis
In the cytoplasm, glucose splits into 2 pyruvic acids & ENERGY is released.
NADH is produced (Goes to Electron Transport Chain)
2 NET ATP are produced

7. Where Pyruvic Acid goes:
A. No oxygen: it stays in the cytoplasm for anaerobic respiration
B. Yes oxygen: it travels into the mitochondria for aerobic respiration

8. In the presence of oxygen, pyruvic acid travels to the mitochondria
The 2 NADH produced in glycolysis are shuttled directly over to the Electron Transport Chain

9. 2) Krebs Cycle Oxygen MUST be present
Occurs in the mitochondrial matrix

10. 2) Krebs Cycle
1. Pyruvic acid enters the mitochondria and is converted to citric acid

11. 2) Krebs Cycle
2. Energy molecules (NADH and FADH2) are produced to carry electrons to the electron transport chain.

12. 2) Krebs Cycle .
3. CO2 is released as waste; breathed out when you exhale
2 ATPs are produced

13. Turn to a Partner What are the products of the Krebs Cycle? (4)
Using the diagram, walk your partner through the steps of the Krebs cycle
What are the products of the Krebs Cycle? (4)
Which continue to the electron transport chain?
# of ATPs produced?

14. NADH & FADH2 Continue to the Electron Transport Chain

15. 3) Electron Transport Chain (ETC)
Occurs in the cristae (mitochondrial membrane)
(For prokaryotes it occurs in the cell membrane.)

16. 3) Electron Transport Chain (ETC)
1. NADH & FADH2 enter the cristae.

17. 3) Electron Transport Chain (ETC)
2. They lose their hydrogens (H+) and electrons (e-) to be shuttled through the ETC.

18. 3) Electron Transport Chain (ETC)
3. Electrons are accepted by oxygen and combines with H+, forming water that is released into the cell

19. 3) Electron Transport Chain (ETC)
4. H+ builds up inside the cristae and is passed through transport protein (ATP synthase) adding ADP and P to form ATP.

20. ETC continued… ETC Produce 32 - 34 ATP
NOTE: 2 ATP are used by transport proteins to move NADH from glycolysis into the ETC.
This results in a Net Gain of 32 ATP from the ETC.

21. What are the products of the ETC? (2)
Turn to a Partner
What are the products of the ETC? (2)

22. Cellular Respiration Recap

23. What is the total # ATP from 1 molecule of glucose during cellular respiration?
36 ATP from Aerobic Respiration
(=with Oxygen)
38% of total energy in glucose is held in the bonds of ATP produced
62% released as heat

24. Cornell Summary