生理学英文练习题-第一章-绪论

CHAPTER 1 INTRODUCTION

Summary

Physiology is the study of how living organisms work. It is the science that describe the normal functions and their regular patterns of the living organisms. The vast field of physiology can be divided into viral physiology, bacterial physiology, cellular physiology, plant physiology, human physiology,and many more subdivisions. However, the Human Physiology is very important and basic biomedical course for medical students.

The body has three fundamental characteristics of living organism which are metabolism, excitability and reproduction. The metabolism include material metabolism and energy metabolism. The material metabolisms of carbonhydrate, lipid, proteins etc. have mainly been learned in BIOCHMISTRY. The energy metabolism will be learned in the 7th Chapter in PHYSIOLOGY. The excitability is very important physiological term, the property of living organisms that permit them to react to stimuli is defined as excitability.

Since the normal functions of organs or organ systems was emphasized, homeostasis is another very important physiological concept. Homeostasis signifies a stable and constant status of the internal enviroment in the body of living organism. It is a dynamic balance of pH, osmostic pressure, temperature, ions concentrations, and so on. Homeostasis is a necessary for the normal functions of cells, organs and organ systems. Therefore, homeostasis is the soul concept of PHYSIOLOGY.

The living organism needs to overcome the possible disorder caused by the metabolisms, then homeostasis could be maintained and the normal functions of the living organisms could be gone on. How to maintain the homeostasis? There are mainly three mechanisms to maintain the homeostasis. They are neural regulation, humoral regulation and auto-regulation. Three regulatory patterns exhibit different mechanisms and features.

Feedback, a term borrowed from engineering, is a fundamental feature of homeostasis. Feedback regulation anticipates changes in a regulated variable, improves the speed of the body’s homeostatic responses, and minimizes fluctuations in the level of the variable being regulated. In the negative feedback system, a change in the variable being regulated brings about response that tend to push the variable in the direction opposite to the original change. The homeostasis could be maintained after negative feedback regulation. In positive feedback system, an initial disturbance in the system sets off a train of events that increases the disturbance even further. Some special physiological activities in the living organism are carried out by the positive feedback system such as processes of giving birth, blood coagulation, micturition.

Definition

1.Physiology（生理学）

2.Acute experiment（急性实验）

3.Chronic experiments（慢性实验）

4.In vitro（离体）