1. PHOTOSYNTHESIS
Photosynthesis occurs in the chloroplasts of plant cells, algae and in the cell membrane of certain prokaryotes.
light
6CO H2O C6H12O O2
glucose

2. pigments – structures containing light absorbing substances.
chlorophyll – the primary pigment involved in photosynthesis; chlorophyll a and chlorophyll b
carotenoids – a pigment that absorbs a different wavelength of light than chlorophyll; gives leaves their fall colors
thylakoids – membranes of disk-shaped structures in the chloroplast that captures energy

3. Stage 1: Absorption of Light
Pigment molecules in the thylakiods of chloroplast absorb light energy.
Thylakoids

4. Stage 2: Conversion of Light Energy to Chemical Energy
Electrons in the pigment are excited by light and move through an electron transport chain.
Stage 3: Storage of Chemical Energy
Carbon atoms from CO2 in the atmosphere are used to make organic compounds (sugars) in which chemical energy is stored.

5. Stage 1
Stage 2
Stage 3
electron transport
chain

6. light-dependent reactions – Stage 1
(light reactions) Stage 2
light-independent reaction – Stage 3
(dark reactions)

7. Which metabolic process is shown at letter A?
C6H12O6

8. Factors that affect Photosynthesis:
1. light intensity
2. CO2 concentration
3. temperature