1. KEY CONCEPT
Photosynthesis produces glucose that stores chemical energy.

2. The equation for Photosynthesis is:
6CO2 + 6H2O C6H12O6 + 6O2

3. Photosynthesis occurs in chloroplasts.
Chloroplast Structure
Thylakoids
Contains chlorophyll in its outer membrane
Grana
Stack of thylakoids
Stroma
Protein substance around the grana
chloroplast
stroma
grana (thylakoids)

4. Steps of Photosynthesis
(1) Light absorption reaction
* Chlorophyll absorbs light energy
(2) Light dependent reaction
* H2O is broken and O2 released
Light independent reaction
* Calvin Cycle: CO2 enters, cycle repeats 6 times, glucose is produced

5. Light Absorption Reaction
Light waves hit chlorophyll
chloroplast
leaf cell
leaf

6. Light Dependent Reaction
Occurs in the Thylakoid
The chlorophyll (which absorbed the light energy) releases high energy electrons.
These high energy electrons break water molecules, releasing oxygen and H atoms.
The oxygen diffuses out to the atmosphere.

7. Light Dependent Reaction (overall view)

8. Light Independent Reaction
Occurs in the Stroma
CO2 from the atmosphere diffuses into the stroma.
In the Calvin Cycle, molecules of CO2 bond to other molecules.
The Calvin Cycle repeats 6 times to form one glucose molecule.

9. Light Independent Reaction (overall view)

10. Photosynthesis (full visual)
Pigments are in thylakoids
C6H12O6
granum (stack of thylakoids)
thylakoid
sunlight
1 six-carbon sugar
6H2O
6CO2
6O2
chloroplast 1 2 4 3
energy
stroma (fluid outside the thylakoids)