1. Photosynthesis What do you know….?
Production of carbon compounds using light
Energy conversion(light  chemical energy)

2. Experiment: Testing a leaf for starch

3. Action & absorption spectra of photosynthesis
Energy for photosynthesis comes from light
Electromagnetic energy, travels in waves with specific wavelengths.
Visible light is used by plants
Visible light 400 – 740nm. Short wavelengths have more energy than long ones.
Different pigments in chloroplasts absorb different wavelengths.

4. Action spectra = rate of photosynthesis at particular wavelengths.
Absorption spectra of common photosynthetic pigments.
Action spectra = rate of photosynthesis at particular wavelengths.
Easiest way to measure the rate of photosynthesis is to monitor the production of oxygen

6. Compare the two graphs. What conclusions can you draw?
Blue and red light = greatest absorption, also have highest rates of photosynthesis
Green light absorption is very low. Corresponds to low rate of photosynthesis.
Are absorption and action spectrum the same for all plants? Why/why not?

7. Experiment:
Separating photosynthetic pigments by chromatography
Method on moodle.