1. PHOTOSYNTHESIS What do you know? What do you want to know?

2. Photosynthesis uses sun energy to make sugar (glucose) (
Plants and algae only
Autotrophs- make their own food
Heterotrophs- can’t make their own food
All living organisms ( including plants) use cellular respiration to get energy from their food
Next slide equation

4. Photosynthesis EQUATION
Sunlight+6CO2+ 6H20 C6H12O6 + __O2
Reactants- light , carbon dioxide, & water
Products: sugar and oxygen

5. Light & Pigments
Sunlight is “white” but contains mixtures of visible wavelengths
Chlorophyll is a PIGMENT in the chloroplast of the plant cell that absorbs light
Did we see chlorplasts in the onion? Why not!!!

8. Leaves absorb blue-violet & red-orange light very well - Green light is reflected- why plants look green!

10. Types of Pigments Chlorophyll a Chlorophyll b Xanthophyll Carotene
Absorbs all colors of light
except green
Plays major role in light
reactions of photosynthesis
Chlorophyll b
Appears yellow-green
Absorbs additional light
Xanthophyll
Yellow pigment
Carotene
Red & orange pigments
Major
Pigments
Minor
Pigments

11. LOCATION OF PHOTOSYNTHESIS
Chloroplasts organelle in plant cells
Chloroplast- many hang out in the middle of the leaves ( mesophyll )

12. CHLOROPLAST STRUCTURE
** Chloroplast has double membrane **
Thylakoids: sac-like photosynthetic
membranes
Arranged in stacks called GRANA
Have chlorophyll and other pigments
Stroma: Fluid area surrounding
thylakoids

13. Print this for CP!!
Boozeman 5:00 Minutes

14. * Light-Dependent:
takes place in
thylakoids-
* Calvin Cycle:
stroma

15. Light Reaction Chlorophyll molecules in thylakoid capture light energy
This energy releases electrons from H2O
H2O then splits into O2 and H+
Oxygen is a "waste product" & escapes to the atmosphere
4 steps

16. So what happens to the electrons and hydrogen ions?
Light Reaction
So what happens to the electrons and hydrogen ions?
Chloroplasts use them to make an energy-rich molecule called NADPH and ATP
The overall result of the light reaction?
Light + H Oxygen + NADPH + ATP

17. Light reaction is charging up the “battery” needed to synthesize sugars in Calvin Cycle
- ADP and NADP+ recycle

18. Calvin Cycle Does NOT use light at all
Can use energy that was made in light cycle to form sugar

19. The Calvin Cycle Occurs in the STROMA.
Uses CO2 and energy powered by ATP and NADPH to produce sugar
NAPDH and ATP are recycled back to the Light Cycle for “recharging”

20. Reactants:
Products:

21. Two Processes
Calvin Cycle
Light Reaction

22. Online Activity 8.1-
Animation of Light and Dark Cycles
Page 6 –Start

23. Factors Affecting Photosynthesis
Temperature
Light intensity

24. Carbon Cycle