Physiology

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Physiology Da-Nian Zhu
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Chapter 1
INTRODUCTION
1. Physiology its research field ?
Definition of physiology ? The task of
physiological research How
Why Influence of environment
Adaptation and regulation
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? Relationship between medicine physiology
Physiology is one of basic medical sciences ?
Three levels of physiological research
Cellular molecular level Organic
systemic level Integrative level ? Methods
of physiological research Acute and
chronic animal experiment in vitro in
vivo experiment molecular biological
experiment
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2. Internal environment of the body ? Body
fluid (60 of body weight)
Intracellular fluid (40) Extracellular
fluid (20) Plasma (5)
Interstitial fluid (15) Lymph
(lt1) Cerebrospinal fluid (lt1)
Aqueous humor (lt1) etc.
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Distribution transfusion of body fluid
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? Concept of internal environment (1870)
By Claude Bernard
(1813-1878) milieu interne milj?
int?n French ? Concept of homeostasis
(1920) By W. B.
Cannon (1871-1945) ? Importance of maintaining
the homeostasis Enough nutritional
substances O2 Low level of metabolic
products CO2 Water, electrolyte,
acid-base balance Temperature, osmotic
pressure, etc. ? Homeostasis is a dynamic
equilibrium ? Regulation of homeostasis
Involve all systems, especially the lung kidney

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3. Regulation of physiological function ?
Nervous regulation Definition the
characteristics Reflex reflex arc
? Humoral regulation Definition the
characteristics Hormone its secretory
forms Telecrine, paracrine,
neurosecretion, etc. ? Autoregulation
Definition the characteristics
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Reflex reflex arc
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4. Automatic control system in the body ?
Non-automatic control system Open loop
system ? Feedback control system
Closed loop system, Automatic control
Negative feedback system Positive
feedback system ? Feed-forward control
system More quickly, less oscillated
foresighted
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Feed-forward signals
Receptor
Effector
Center
Feedback signals