Overview of Photosynthesis - Diagrams from UC Davis

The Light Dependent Reactions

1. The Light Dependent Reactions of photosynthesis occur on the thylakoid membranes of the chloroplast. Using the diagram below describe the path of electrons through the "Z scheme" pictured below and answer the following questions.

2. The electron pathway through the "Z scheme" is non-cyclic, where does the supply electron come from and where do they end up ?

3. What products result specifically from photosystem I and photosystem II ?

4. What substances are necessary as reactants for the light dependendent reactions and what substances would be produced as a result of these reactions ?

5. The diagram below illustrates the activities of light dependent reactions as they occur on the thylakoid membranes. How is the electrochemical gradient, needed for chemiosmosis, being established with respect to the thylakoid membrane ?

5. What three activities pictured above contribute to the strength of the electrochemical gradient ?

6. Briefly describe how the establishment of an electrochemical gradient can be used to synthesize ATP ?