This course explains the physiological mechanisms that are important for the life of the organism, carried out by all systems in the body of invertebrate and vertebrate animals. The information will emphasize to the topics such as an introduction to the principles of physiological systems, cell signaling and endocrine regulation, structure and function of neurons, the movement of cells and muscles, sensory, circulatory, respiratory, urinary, digestive and reproduction system utilizing the concepts of comparative, anatomy and functional approaches.