Book excerpt: PhysioEx™ 9.0: Laboratory Simulations in Physiology with 9.1 Update is an easy-to-use laboratory simulation software and lab manual that consists of 12 exercises containing 63 physiology lab activities that can be used to supplement or substitute wet labs. PhysioEx allows you to repeat labs as often as you like, perform experiments without harming live animals, and conduct experiments that are difficult to perform in a wet lab environment because of time, cost, or safety concerns. PhysioEx 9.1 features input data variability that allows you to change variables and test out various hypotheses for the experiments. 9.1 retains the popular new improvements introduced in 9.0 including onscreen step-by-step instructions and “Stop & Think” and “Predict” questions that help you think about the connection between the experiments and the physiological concepts they demonstrate.