1. Chapter 8 Cellular Energy

2. Cooperative Activity
What do you know about energy?

3. Energy - what we know Cannot be created or destroyed Can change forms
Stored in chemical bonds

4. Energy - what we know (cont.)
Released when bonds are broken
Needed to form bonds

5. Review: Chemical Reactions
Chemically changing substances
Metabolism: sum of all the chemical reactions that occur in our body

6. Review: Chemical Reactions (cont.)
Chemical equations show how substances change
Reactants  Products
Na + Cl  NaCl

7. Photosynthesis

8. Photosynthesis How plants convert solar energy into glucose
Takes place in chloroplasts

9. Why is it called photosynthesis?
Photo means “light”
Synthesis means “to put together”
What are we putting together?
glucose

10. Chloroplasts Capture light Contain pigments like chlorophyll

12. Chloroplasts & Chlorophyll

13. Accessory Pigments
Chlorophyll = main pigment
Each pigment reflects a different color

14. Accessory Pigments (cont.)
Carotene – Orange
Xanthophyll – Yellow
Anthocyanin – Red

15. Phases of Photosynthesis
Sunlight is converted into ATP (aka light reaction)
ATP is converted into glucose (aka dark reaction)

16. Photosynthesis: Chemical Equation
Reactants
6 CO2 + 6 H2O >
C6H12O6 + 6 O2
Products
Light

17. What affects the rate of photosynthesis?
Light Intensity
Temperature
Water
Other

18. Why do leaves fall off the tree?
Chlorophyll breaks down in cold temps
No use for leaves so they fall off to save energy
Trees hibernate in winter

19. What’s up with that tree?
Why are Japanese Maple trees red?
Do they perform photosynthesis?

20. ATP (Adenosine Tri-Phosphate)
Portable form of energy
“Energy currency”
Delivers energy where needed in cell

21. Cellular Respiration
Process of releasing energy stored in the bonds of glucose

22. Step 1 – Glycolysis
Takes place in cytoplasm
Does not require oxygen (Anaerobic)
2 ATP produced

23. 2. Fermentation (Aerobic)
2 ATP produced
Occurs during rapid & heavy exercise
Feel burning sensation in muscles

24. 2. Respiration Takes place in mitochondria Requires oxygen (aerobic)
34 ATP produced

25. and the total is… 4 ATP: Glycolysis & Fermentation
36 ATP: Glycolysis & Respiration

26. ~ Cellular Respiration ~ The Chemical Equation
Reactants
C6H12O6 + 6 O2 
6 CO2 + 6 H2O + ATP Products

27. Comparing the reactions
Photosynthesis
6 CO2 + 6 H2O + Light  C6H12O6 + 6 O2
Cellular Respiration
C6H12O6 + 6 O2  6 CO2 + 6 H2O + ATP