Plant Pigments and Photosynthesis Lab Report

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Plant Pigments and Photosynthesis Lab Report
Photosynthesis, in a nutshell, is the process that allows plants to capture the sun’s energy and store it as chemical potential energy in the bonds of carbohydrate molecules. There are two processes in which this takes place, called Photosystems. In Photosystem I, light from the sun travels into the chloroplast and goes through the antennae pigment, into the reaction center. The light that travels into the first reaction center is called P700. An electron is then sprung out of the reaction center into the e- transport train, or the cytochrome system. The electron is then taken to NADP+. The NADP+ is then reduced into NADPH. After the loss of the electron from P700, the P700 can no longer function. Photosystem II is then needed. The antennae pigment of Photosystem II absorb light energy of P680. The pigment is exited and transfers this absorbed energy to an electron, causing it to break free, and travel to other electron transport molecules until it reaches P700, replacing its lost electrons. The lost electrons of P680 are replaced by extracting electrons from two water molecules. That leaves four hydrogen ions, that are released into the Thylakoid space, and combine to form some O2. The O2 diffuses out of the cell and out of the plant. The final phase of energy capture is the chemiosmotic synthesis of ATP. It uses the energy from the Hydrogen ions. They work with ATP synthetase enzymes to synthesis ATP from ADP. After energy capture, the ATP and NADPH work to fix the carbon in Carbon Fixation. This is called the Calvin Cycle. Through the Calvin cycle glucose is produced. So basically, Photosynthesis takes place in two main parts. In the first part, energy is captured, in the second part the energy is used to make sugar.
In this lab we were looking for whether or not light and chloroplasts are required for light reactions to occur. The hypothesis would be: If light reactions occur, then ...