PHYSIOLOGY,Yue Limin(岳利民) Department of Physiology School of Preclinical and Forensic Medicine Sichuan University,Two Textbooks: 生理学姚泰 主编 人卫出版社 2005 医学英语原版改编双语教材 ， 科学出版社，2006 Teaching Guide Teaching Outline Teaching Schedule Website of the Dept. of Physiology: http:/219.221.200.61/2006/xiaoji/c20/,Teaching Materials,Teaching references, Textbook of Medical Physiology 10th Ed, by Guyton and Hall Medical Physiology, by Walter F.Boron precise; local,2. Humoral Regulation,Definition: The chemical substances secreted by some special cells are delivered in the extracellular fluid to all of parts of body to regulate cellular functions.,Properties:,Slow ; diffusive; lasting,metabolism; growth ; reproduction,Significancy:,Local: paracrine; autocrine; neurocrine,N-H Regulation :Extension of N. Regulation,.,paracrine,3. Autoregulation being independent of either neural or humoral factors local; limited,IV. Principle of Automatic Control of Physiological Functions Cybernetics,Non-automatic Control System (Open Loop),Automatic Control System-Feedback Control (Closed Loop ),Feed-forward Control System,Three control systems:,1) Components,-Closed Loop,Property: Bidirectional communication of signal,output variable,2) Types,Negative Feedback:,Definition: The role of the feedback signal is opposite to the previous control signal or to the activity of controlling system.,Significance: to keep the functional activity being constant or homeostasis,(),Example of Negative Feedback the thermostat,Positive Feedback:,Definition: The role of the feedback signal is to increase the previous activity of controlling system.,Significance: to keep the functional activity going on until its end.,(),Deliverying process:,Uterine contraction,Dilation of cervix,Posterior pituitary,oxytocin,+,2. Feed-forward Control,Definition: controlled system adjusts its activities by feed-forward signal before the variation of output variable (before feedback signal reaches it).,Significance: to avoid possible variation of the output variable,Feed-forward signal,Summary,Physiology is to study all of the life activities of living organisms on the three leves,Internal Environment is the actual enviroment in which cells of body live directly-extracellular fluid, ECF,Homeostasis is relatively constant state of physical and chemical properties of internal environment,Main types of regulation on physiological function are nervous regulation, humoral regulation and autoregulation,Negative feedback is to keep functional activities being constant,What are internal environment and its characteristic,What are reflex and its structural basis,What are physiology and levels of physiological study,Problems:,What are nervous regulation and humoral regulation and their properties,What are homeostasis and its its significance,What are negative feedback and the significance of this regulating mechanism,How is homeostasis maintained in the body,