This class introduces students the most important concepts in biochemistry, enable them to explore complicated phenomena in life science. To achieve that, the class focuses on the following topics: thermodynamics, water chemistry and weak bonds, structure and function of biological molecules, enzyme kinetics and its regulation. Some basic metabolic pathways involving important molecules, such as carbohydrate, lipids, and nitrogen-containing compounds, may also be introduced briefly during the lectures. Significance of these metabolic pathways in living things will be highlighted.