In the pdf below, we have included a description of the PvACR2 and the PvPht1;3 equillibrium, and it's role in the Pteris Vittata arsenic tolerance mechanism. We have included diagrams of the proteins and performed calculations to calculate the arsenic out and arsenic in values to model the substate concentrations needed for the proteins to work in accordance with each other. To add, we have also included all our constants, unit conversions, and graphs from Matlab. To explain the graphs and equillibrium in further detail, we have also included the files to our Matlab code, and screenshots of the code itself.