1. U N I T I Textbook of Medical Physiology, 11th Edition GUYTON & HALL Copyright © 2006 by Elsevier, Inc. Chapter 1: Functional Organization of the Human Body and Control of the “Internal Environment” Slides by John E. Hall, Ph.D.

2. Copyright © 2006 by Elsevier, Inc. Physiology The science that is concerned with the function of the living organism and its parts, and of the physical and chemical processes involved.

3. Copyright © 2006 by Elsevier, Inc. The study of disordered body function (i.e. disease) The basis for clinical medicine Pathophysiology

4. Copyright © 2006 by Elsevier, Inc. Anatomy The study of the structure of the body.

5. Copyright © 2006 by Elsevier, Inc. The Human Body - A Complex Society of Differentiated Cells Cells: the basic structural and functional unit (~ 100 trillion) Tissues: (e.g. muscles, epithelial, nervous ) Organs: (e.g. kidney, heart, liver, pancreas) Organ systems: (e.g. cardiovascular, urinary)

6. Copyright © 2006 by Elsevier, Inc. Figure 1-2; Guyton & Hall Exchange Between the Capillaries and Interstitial Fluid

7. Copyright © 2006 by Elsevier, Inc. Negative Feedback Control of Arterial Pressure Promotes Stability Art. Pressure Sympathetic Activity Heart Rate Vasoconstriction

8. Copyright © 2006 by Elsevier, Inc. Baroreceptor Reflex : Negative Feedback System - Promotes Stability Blood vessels, Heart Baroreceptors Set-point Error signal Vasomotor Centers Sympathetic System Effectors Blood Pressure Sensor Controlled Variable +

9. Copyright © 2006 by Elsevier, Inc. Cardiopulmonary Reflexes: Feed-Forward Control of Blood Pressure – Anticipates a Change Blood vessels, Heart Baroreceptors Error signal Vasomotor Centers Sympathetic System Effectors Blood Pressure Sensor Controlled Variable Set-point Cardiopulmonary Receptors Cardiopulmonary Pressures +

10. Copyright © 2006 by Elsevier, Inc. Feedback and Feed-Forward Control Negative feedback: promotes stability Feed-forward: anticipates change Positive feedback: promotes a change in one direction, often leading to instability, disease, and sometimes death.

11. Copyright © 2006 by Elsevier, Inc. Positive Feedback of Hemorrhagic Shock Figure 1-3; Guyton & Hall

12. Copyright © 2006 by Elsevier, Inc. Hemorrhagic Shock: Positive Feedback Severe Hemorrhage Venous Return Cardiac Output Blood Pressure Coronary Blood Flow Cardiac Contractility +