This miniprogram was designed to give students a basic understanding of enzyme kinetics. In the first experiment in this series, students prepare an extract from wheat germ. They then determined the initial velocity (Vo) of the reaction catalyzed by purified acid phosphatase and by the acid phosphatase activity present in the extract. From these data, they estimate the amount of the enzyme that is present in the wheat germ. In the second experiment, the student examines the effects of substrate concentration on the reaction velocity. Data are analyzed using Michaelis-Menton and Lineweaver-Burk plots and students calculate values of Vmax and Km.