Chapter 1 *Lecture PowerPoint Major Themes of Anatomy and Physiology *See separate FlexArt PowerPoint slides for all figures and tables preinserted into PowerPoint without notes. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Introduction • Anatomy and physiology (A&P) is about human structure and function—the biology of the human body • We want to know how our body works! • A&P is a foundation for advanced study in health care, exercise physiology, pathophysiology, and other health-care-related fields • Considers the historical development and a central concept of physiology—homeostasis 1-2 The Scope of Anatomy and Physiology • Expected Learning Outcomes – Define anatomy and physiology and relate them to each other. – Describe several ways of studying human anatomy. – Define a few subdisciplines of human physiology. 1-3 Anatomy—The Study of Form • Examining structure of the human body – Inspection – Palpation – Auscultation – Percussion • Cadaver dissection – Cutting and separation of tissues to reveal their relationships • Comparative anatomy Figure 1.1 – Study of more than one species in order to examine structural similarities and differences, and analyze evolutionary trends 1-4 Anatomy—The Study of Form • Exploratory surgery – Open body and take a look inside • Medical imaging – Viewing the inside of the body without surgery – Radiology—branch of medicine concerned with imaging • Gross anatomy – Study of structures that can be seen with the naked eye • Cytology – Study of structure and function of cells • Histology (microscopic anatomy) – Examination of cells with microscope • Ultrastructure – View molecular detail under electron microscope • Histopathology – Microscopic examination of tissues for signs of disease 1-5 Physiology—The Study of Function • Subdisciplines – Neurophysiology (physiology of nervous system) – Endocrinology (physiology of hormones) – Pathophysiology (mechanisms of disease) • Comparative physiology – Limitations on human experimentation – Study of different species to learn about bodily function • Animal surgery • Animal drug tests – Basis for the development of new drugs and medical procedures 1-6 The Origins of Biomedical Sciences • Expected Learning Outcomes – Give examples of how modern biomedical science emerged from an era of superstition and authoritarianism. – Describe the contributions of some key people who helped to bring about the transformation. 1-7 Greek and Roman Legacy • Physicians in Mesopotamia and Egypt – 3,000 years ago used herbal drugs, salts, and physical therapy • Hippocrates, the Greek physician – ―Father of medicine‖ – Established a code of ethics (Hippocratic Oath) – Urged physicians to seek natural causes of disease rather than attributing them to acts of the gods and demons 1-8 Greek and Roman Legacy • Aristotle – One of the first philosophers to write about anatomy and physiology – Believed that diseases had either supernatural causes or physical causes • Called supernatural causes of disease theologi • Called natural causes for disease physiologi • This gave rise to the terms physician and physiology – Believed that complex structures are built from simpler parts 1-9 Greek and Roman Legacy • Claudius Galen – Physician to the Roman gladiators – Did animal dissections since use of cadavers was banned in his time – Saw science as a method of discover, not just a body of facts taken on faith – Wrote book advising followers to trust their own observation more than the teaching of dogma of the ―ancient masters‖ 1-10 The Birth of Modern Medicine • Christian culture of Europe in Middle Ages – Science severely repressed – Taught medicine primarily as dogmatic commentary on Galen and Aristotle – Crude medical illustrations • In Jewish and Muslim cultures free inquiry was less inhibited • Jewish physician Maimonides (Moses ben Maimon) – Wrote 10 influential medical texts – Was physician to Egyptian sultan, Saladin • Avicenna (Ibn Sina) from Muslim world – ―The Galen of Islam‖ – Combined Galen and Aristotle findings with original discoveries – Wrote The Canon of Medicine, used in medical schools for 500 years 1-11 The Birth of Modern Medicine • Andreas Vesalius – Taught anatomy in Italy – Catholic Church relaxed restrictions on dissection of cadavers and permitting autopsies – Barbering and surgery were considered ―kindred arts of the knife‖ – Performed his own dissections rather than the barber-surgeons – Published first atlas of anatomy, De Humani Corporis Fabrica (On the Structure of the Human Body) in 1543 1-12 The Birth of Modern Medicine • William Harvey – Early physiologist—contributions represent the birth of experimental physiology – Remembered for early studies on blood circulation – Realized blood flows out from heart and back to it again – Published book De Motu Cordis (On the Motion of the Heart) in 1628 • Michael Servetus – Along with Harvey, they were the first Western scientists to realize that blood must circulate continuously around the body, from the heart to other organs, and back to the heart again 1-13 Early Medical Illustrations Figure 1.2 Figure 1.3 1-14 The Birth of Modern Medicine • Robert Hooke – Made many improvements to the compound microscope— two lenses: ocular lens (eyepiece) and objective lens (near specimen) • Invented specimen stage, illuminator, coarse and fine focus controls • His microscopes magnified only 30X • First to see and name ―cells‖ – Published first comprehensive book of microscopy (Micrographia) in Figure 1.4 1665 1-15 The Birth of Modern Medicine • Antony van Leeuwenhoek – Invented a simple (single-lens) microscope with great magnification to look at fabrics (200X) – Published his observations of blood, lake water, sperm, bacteria from tooth scrapings, and many other things • Carl Zeiss and Ernst Abbe – Greatly improved compound microscopes – Added condenser and superior optics • Eliminated blurry edges (spherical aberration) and rainbowlike distortions (chromatic aberration) 1-16 The Birth of Modern Medicine • Matthias Schleiden and Theodor Schwann – With improved microscopes, examination of a wide variety of specimens followed – Concluded that ―all organisms were composed of cells‖ – First tenet of cell theory • Considered as the most important breakthrough in biomedical history • All functions of the body are interpreted as effects of cellular activity 1-17 Living in a Revolution • Modern biomedical science – Technological enhancements • Advances in medical imaging have enhanced our diagnostic ability and life-support strategies • Genetic Revolution • Human genome is finished • Gene therapy is being used to treat disease • Early pioneers were important – Established scientific way of thinking – Replaced superstition with natural laws 1-18 Scientific Method • Expected Learning Outcomes – Describe the inductive and hypothetico– deductive methods of obtaining scientific knowledge. – Describe some aspects of experimental design that help to ensure objective and reliable results. – Explain what is meant by hypothesis, fact, law, and theory in science. 1-19 Scientific Method • Francis Bacon, in England, and René Descartes, in France – Philosophers who invented new habits of scientific thought – Sought systematic way of seeking similarities, differences, and trends in nature and drawing useful generalizations from observable facts • Governments of England and France – Established academies of science that still exist today • Science and scientific methods – Set standards for truth 1-20 The Inductive Method • Described by Francis Bacon – Making numerous observations until one becomes confident in drawing generalizations and predictions from them – Knowledge of anatomy obtained by this method • Proof in science – Reliable observations – Tested and confirmed repeatedly – Not falsified by any credible observation • In science, all truth is tentative – ―Proof beyond a reasonable doubt‖ 1-21 The Hypothetico–Deductive Method • More physiological knowledge gained by this method • Investigator asks a question • Formulates a hypothesis—an educated speculation or possible answer to the question – Characteristics of a good hypothesis • Consistent with what is already known • Testable and possibly falsifiable with evidence 1-22 The Hypothetico–Deductive Method • Falsifiability—if we claim something is scientifically true, we must be able to specify what evidence it would take to prove it wrong • Hypothesis—to suggest a method for answering questions: written as ―if–then‖ statements 1-23 Experimental Design • Sample size – Number of subjects used in a study – Controls for chance events and individual variation • Controls – Control group and treatment group – Comparison of treated and untreated individuals • Psychosomatic effects – Effects of the subject’s state of mind on his or her physiology – Use of placebo in control group 1-24 Experimental Design • Experimenter bias – Prevented with double-blind study • Statistical testing – Provides statements of probability – Difference between control and test subjects was not random variation – Results due to the variable being tested 1-25 Peer Review • Critical evaluation by other experts in the field – Done prior to funding or publication – Done by using verification and repeatability of results • Ensures honesty, objectivity, and quality in science 1-26 Facts, Laws, and Theories • Scientific fact – Information that can be independently verified by a trained person • Law of nature – Generalization about the predictable way matter and energy behave •