Fig. 13. Graphs of WECB elastic modulus based on the three treatments: formic acid, citrate/phosphate buffer changes, and temperature exposure. Open symbols represent the yield region and filled symbols represent the Hookean region. Elastic modulus of the yield region appears to remain fairly constant throughout the treatments. Hookean elastic modulus either remains fairly consistent or decreases. At the extreme of each of the treatments [i.e. high temperature, strong formic acid concentration at longer incubation times (1 h) and low pH] the Hookean region disappears completely so no modulus can be determined. Values are means ± s.e.m. (N=2-5).