Chapter 16, Problem 24P

You are studying similarities and differences in how organisms respond to high salt concentrations and high temperatures. You begin your investigation by using microarrays to compare gene expression patterns of S. cerevisiae in normal growth conditions, in $\text{high-salt}$ concentrations, and at high temperatures. The results are shown here with the values of red and green representing the extent of the increase and decrease, respectively, of expression for genes $\text{a–s}$ in the experimental conditions versus the control (normal growth) conditions. What is the first step you will take to analyze your data?