Human Physiology Zou Yuan, PhD Department of Physiology Dalian Medical University
What is Physiology? • A branch of biological science. • To study normal functions of organs and organ systems of the body.
What will be learn in Physiology • Physiological function of organs
Blood Circulation Blood
Respiration Digestion and Absorption
Energy Metabolism and Body temperature Regulation
Kidney The Nervous System
Two themes of Physiology • Homeostasis • Integration
Developmental History of Physiology William Harvey(1578-1657) An english physician who, by observing the heart in small animals and fishes, proved experimentally that heart receives and expels blood during each cycle, found valves in the veins and the flow of blood in one direction. He developed the first complete theory of the circulation of blood. He published his observations and interpretations in Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus (1628), often abbreviatedDe Motu Cordis.
W. Beaumont (1785-1853) American frontier doctor who treated Alexis Saint Martin, a nineteen-year-old Canadian trapper accidentally wounded in the stomach. When the wound healed, Beaumont observed that a hole remained in the stomach cavity. He used the opportunity to insert and withdraw various foods after varying periods of time and tabulate the results. Pavlov, Ivan Petrovich (1849-1936) Russian physiologist. He received the Nobel prize in medicine and physiology in 1904. stomach secretion and nervous regulation.
1993, Glasgow, Integrative Physiology At present, from gene to function. We can see, the research levels from whole body, to organs, tissues, cells, organelles, and genes.
Methodology • Physiology is a experimental science. • In vivo: perform on the whole animals. • In vitro: perform on isolated tissue or organ. • Acute: perform on the animals under anesthesia. • Chronic: perform on conscious animals for a long time.
Application and significance • Medicine • Need for know ourselves • Need for practice • Plant Physiology, Animal Physiology, and so forth. • Diving Physiology, Aviatic Physiology.
Fundamental Characteristics of Living Organism • Metabolism • Excitability • Reproduction or adaptation
Metabolism: • Catabolism: catabolic reaction, decomposition. • Anabolism: anabolic reaction, synthesis of molecules. • Material metabolism: learned in Biochemistry. • Energy metabolism: will be learned in Physiology.
Excitability: • Definition: A ability of response to environmental stimuli. • Stimulus: changes in external or internal environment. • Physical stimulus: thermal electric phonic photic
Chemical stimulus: • Biological stimulus: chemical substances bacteria, virus
Response: • Excitatory response: excitation • Inhibitory response: inhibition • Essence of excitability: • AP production
Reproduction • A process by which an animal produces one or more individuals similar to itself. • Reproduction makes species succession possibility.
Regulation of Body Functions • Nervous Regulation • Humoral or Neuro-humoral Regulation • Auto-Regulation
Homeostasis • Internal environment: • Cells to live, namely extracellular fluid. • Interstitial fluid, plasma, etc. • Physical and chemical status are stable: T, pH, etc. • Homeostasis: W.B. Cannon • Constant condition of internal environment. • A dynamic equilibrium: CellTissueOrganSystem. • Homeostasis needs regulatory mechanisms.
Nervous Regulation • It is completed under CNS by reflex that the regular response was made to internal or external stimuli under CNS. • Reflex arc: • Sensor, afferent and efferent limbs, reflex center, and effector. • Classification: • Unconditional reflex: congenitally available • Conditional reflex: learned by individual life. • Properties: • Accuracy: reflex arc is stereotyped. • Rapidity: speed of AP
Hormonal or Neuro-hormonal Regulation • It is completed by special chemicals or metabolic products. • Regulative types: • Endocrine: • Paracrine: • Neuro-endocrine: • Properties: • Slow in onset, diffuse in nature, longer in duration.
Auto-regulation • It is completed by a tissue or organ itself, neither on nervous nor humoral control. • Properties: • Local in range • Limited in action
Feedback Control of body function • Feedback: • To feed the output information back to the control so as to modify the nature of control. Physiological information Control element Effector Feedback information
Forms of feed back: • Positive Feedback: • Negative Feedback: • Feed-forward control:
Contents • Chapter 1 Introduction • Chapter 2 The Cell and its Function • Chapter 3 Blood and Body Fluid • Chapter 4 The Heart and Circulatory system • Chapter 5 Respiration • Chapter 6 Digestion and Absorption • Chapter 7 Energy Metabolism and Body temperature Regulation • Chapter 9 The Kidney • Chapter 10 The Nervous System • Chapter 11 The Endocrine system