1. Photosynthesis and Cellular Respiration

2. ATP is used by all cells as their basic energy source
All living things depend on energy
ATP is used by all cells as their basic energy source
Where does this ATP come from?

3. Where does Energy (ATP) come from?
Photosynthesis
Cellular Respiration (aerobic)
What is it for?
Who does it?
Formula
Organelle
Reactions/location
Reactants
Products
If NO oxygen is present, then…

4. Autotrophs Heterotrophs
use light energy from sun to produce food (sugars)
Heterotrophs
obtain energy from the food they consume

5. Photosynthesis
6CO2 + 6H2O C6H12O6 + 6O2
Cellular Respiration

6. Photosynthesis
SUN
6CO2 + 6H2O C6H12O6 + 6O2
glucose

7. Question:
Where does photosynthesis take place?

8. Plant Leaf
Nucleus
Cell Wall
Chloroplast
Central Vacuole

9. Chloroplast Stroma Thylakoid Granum
Organelle where photosynthesis takes place.
Stroma
Thylakoid
Granum

10. Two Parts to Photosynthesis

11. Two main parts of Photosynthesis
Calvin Cycle
aka
Light Independent Rxn
Occurs in the stroma
Uses the ATP and NADPH
Converts CO2 to glucose
Light Dependent Rxn
Occurs in the thylakoids
Captures energy from sun as ATP
NADPH
Produces O2

12. Thylakoid
Has pigment chlorophyll – absorbs light
Granum

13. C6H12O6

14. Question:
Why are plants green?

15. Chlorophyll Molecules
Located in the thylakoid membranes.
Chlorophyll pigments absorb light (blue and red).
Plants are green because the green wavelength is reflected, not absorbed.

16. Thylakoid
Has pigment chlorophyll – absorbs light
Granum

17. Wavelength of Light (nm)
400
500
600
700
Short wave
Long wave
(more energy)
(less energy)

18. Question:
During the fall, what causes the leaves to change colors?

19. Fall Colors
During the fall, the green chlorophyll pigments are greatly reduced revealing the other pigments.

20. What factors affect photosynthesis?
SUN
6CO2 + 6H2O C6H12O6 + 6O2
intensity of sunlight
water
temperature