The textbook, in a well simplified approach, describes some topical concepts that will help the readers to understand the basic biochemical activities that enhance life in various species of organisms. Also,the chemistry, functions and metabolism of such organic compounds as carbohydrates, proteins, lipids, nucleic acids and vitamins, as well as the roles of such organic molecules as enzymes and hormones in biological systems are discussed.In addition, the Text gives a detailed description of the various biological pigments in different species of organisms, as well as some basic biochemical activities and processes in plants.