Environmental impacts on enzyme function

The x axis on the line graph is labeled pH and has labels at 2,4,6,8,10, 12, and 14. The y axis is labeled enzyme activity. There are no marks on the y axis. There are 2 colored lines on the graph, with a key labeled A blue line and B red line. Line A begins at pH 2 and the origin of the y axis, rises sharply and peaks at pH 6, then declines sharply and returns to the y axis origin at pH 10. Line B begins at pH 6 and the origin of the y axis, rises sharply and peaks at pH 10, then declines sharply and returns to the y axis at pH 14. The peaks of Line A and Line B are at the same enzyme activity level.