Electron Transport Chain: A rollercoaster ride that produces energy

Where does the light reaction on Photosynthesis take place?

In the thylakoid membrane

Where is light energy converted into electron flow?

In the reaction center chlorophyll

In what order do the electrons move through the electron transport chain?

Water, photosystem II, photosystem I, NADPH

What is produced during the light reaction? Choose the correct chemical equation

2 H2O + 2 NADP + nPi + hv produce O2 + NADPH + 2H+ + nATP

Where does the electron flow that we measure with DCPIP originate?

Photosystem II

What would be the best negative control?

Remember that a negative control should NOT show change during the experiment.

Keep a sample in the dark

What would be a good positive control for this experiment?

Remember that a positive control should show a change during the experiment.

Expose a sample to visible light

Looking at the water extract, what wavelength should we use to illuminate the treatment sample?

580 nm

If it does transfer energy and the electrons are excited, how will the amount of oxidized (blue) DCPIP change in relation to the controls?

Less oxidized (blue) DCPIP than the negative control

Why do we use DCMU?

We avoid further reduction of DCPIP under the lab light

Looking at the absorbance spectrum in the VIEW IMAGE button, what wavelength should we use?

610 nn

Compare the values obtained for the three samples. Was your hypothesis right?

Is red pigment really a photosynthetic light?

Yes, because photosystem II was active in green light

What is your most important finding?

The red pigment can use green light for photosynthesis