BSCI 105 Study Guide - Midterm Guide: Photosystem I, Light-Dependent Reactions, Light-Independent Reactions

• School: University of Maryland
• Department: Biological Sciences Program
• Course: BSCI 105
• Professor: Keller

Document Summary

The photosystems take in light energy in the form of photons and through a series of processes, convert this into chemical energy. The products of photosystem ii are used as the reactants of photosystem i to excite the electrons. Photosystems use energy from the collected light to carry electrons throughout light reactions. Throughout light reactions, the photosystems produce atp and nadph to be used in the dark reactions (calvin cycle). Photosynthesis can be considered one big reaction coupling process. The calvin cycle fixes carbon by attaching one molecule of co2 to a molecule of rubp using the enzyme rubisco. The product of the calvin cycle is g3p which is used to make starch, a polymer of glucose, in the chloroplast stroma. In the transition step, pyruvate is converted into acetyl coa. This is considered irreversible because as pyruvate is transitioning, co2 and nadp+ are released and used up since co2 is exhaled.