Massage_connection

The Massage Connection ANATOMY AND PHYSIOLOGY

SECOND EDITION The Massage Connection ANATOMY AND PHYSIOLOGY Kalyani Premkumar University of Calgary Canada

Editor: Pete Darcy Managing Editor: Eric Branger Marketing Manager: Christen DeMarco Production Editor: Christina Remsberg Art Director: Jonathan Dimes Artwork: Dragonfly Media Group, Mark Miller Medical Illustration, Kim Battista, Mary Anna Barratt, and Susan Caldwell Compositor: Graphic World Printer: RR Donnelly-Willard Copyright © 2004 Lippincott Williams & Wilkins 351 West Camden Street Baltimore, Maryland 21201-2436 USA 530 Walnut Street Philadelphia, PA 19106 All rights reserved. This book is protected by copyright. No part of this book may be reproduced in any form or by any means, including photocopying, or utilized by any information storage and retrieval system with- out written permission from the copyright owner. The publisher is not responsible (as a matter of product liability, negligence, or otherwise) for any injury re- sulting from any material contained herein. This publication contains information relating to general princi- ples of medical care that should not be construed as specific instructions for individual patients. Manufac- turers’ product information and package inserts should be reviewed for current information, including contraindications, dosages, and precautions. Printed in the United States of America Library of Congress Cataloging-in-Publication Data The publishers have made every effort to trace the copyright holders for borrowed material. If they have inadver- tently overlooked any, they will be pleased to make the necessary arrangements at the first opportunity. To purchase additional copies of this book, call our customer service department at (800) 638-3030 or fax orders to (301) 824-7390. International customers should call (301) 714-2324. Visit Lippincott Williams & Wilkins on the Internet: http://www.LWW.com. Lippincott Williams & Wilkins customer service representatives are available from 8:30 am to 6:00 pm, EST. 04 05 06 07 1 2 3 4 5 6 7 8 9 10

To my dad, D.I. Paul (deceased), and my mother, Stella Paul, who lovingly supported me (financially and otherwise) throughout my undergraduate and postgraduate education and to my parents-in-law, A.G. Vedasundararaj (deceased) and Helen Vedasundararaj, who believed that I could use my medical education for the good of others.

Preface T he first edition of this book was written to meet the specific needs of massage ther- apy students and profession and to simplify the learning and teaching of anatomy and physiology. It was a result of having shared the intense frustration of massage therapy students as they tried to weed out irrelevant details from texts written for medical and nursing students and focus on what they needed to know for their profession. The specific requirements for the book were painstakingly determined by scrutinizing the curriculums of many massage therapy schools in the United States and Canada. In addition to personal experience, the input from massage therapy students and therapists was used to organize the objectives and contents of the book. The first edition was well received. As with any product, there is always scope for improvement; however, improvements are best made based on feedback from all stakeholders. Changes and additions made to the second edition are based on feedback from those who actually use the book—the massage therapy students, instructors, practitioners, and policy makers. The first edition was organized into three major divisions—anatomy and physiology— system-wise; topics in pathology; and case studies in relation to each body system. Based on feedback, the second edition is compiled as one major section, with each chapter dis- cussing one body system. Important pathology topics and relevant case studies have been incorporated into each chapter. A chapter outline and a detailed list of objectives are given at the beginning of each chapter to help the student construct a conceptual framework and identify the key points. Each chapter is interspersed with information boxes that describe pathologies relevant to the anatomy and physiology topic under study. Also included are boxes that give specific information relevant to massage therapists. All new terms and key terms are shown in boldface throughout the text. New to this edition is the inclusion of additional illustrations—and colorful ones at that. Color was significantly absent in the previous edition. Extensive review questions, with answers and pictures for labeling and coloring, are given at the end of each chapter to assess the understanding of basic concepts intro- duced. Case studies, giving typical scenarios that the therapist may encounter in the clinic, have been included. This will place the study of each system in the right context and encourage problem solving. The case studies may be used for discussion after the study of the chapter or used as a starting point for the study of individual systems. Exciting advances have been made in the field of massage therapy since the publica- tion of the first edition. Additional books have been published. A number of authentic studies have been published on the use and effects of massage therapy on the body. Sys- tematic studies on the effects of specific massage techniques for various diseases and conditions are also underway. It is important for these findings and advances to be in-

viii The Massage Connection: Anatomy and Physiology corporated into any textbook; the second edition strives to do so. The proven effects of massage on each body system have been added at the end of every chapter, based on cur- rent findings and including suggestions for additional reading. In recent years, massage therapy schools and associations have taken steps to reform the curriculum. This required revisiting the curriculum for the second edition. Based on curriculum changes, detail has been added to every chapter. Major revisions have been made to the chapters dealing with the muscle, skeletal, and nervous systems. Tables have been added that include origin, insertion, action, and innervation of muscles, together with illustrations of individual muscles. Tables listing muscles that produce specific movements across joints give the student a different perspective of muscles. Illustrations of muscles grouped together, bones indicating origins and insertions of various muscles, and photographs with bony landmarks are features that massage therapy students will find useful. The comprehensive index and the glossary at the end of the book have been specifi- cally designed for ease in locating important terms, topics, and concepts. By converting to hard cover, the book is now sturdier to withstand frequent handling. This change was based on feedback from students and practitioners who used the previ- ous edition as a text. In addition to the new features for students and practitioners, new resources have been created for instructors. Instructors will find the images from the book and PowerPoint slides for each chapter on the connection companion Web site ?????????. Also available is the Test Generator for The Massage Connection: Anatomy and Physiology, 2nd Edition. This CD-ROM contains test questions and answers for all twelve chapters and allows users to design their own tests and answer keys. With the software, instructors are able to select, delete, edit, or add questions to the tests they create. It is encouraging that the public is increasingly turning to alternative and comple- mentary practitioners for their health care needs. As such changes occur, it is important that the education of these practitioners be reformed to meet this societal need. It is en- visaged that this new edition, written for massage therapists and including all the rele- vant content that they need to practice, will move therapists in this direction.

Acknowledgments I am greatly indebted to many individuals who helped with the preparation of the book. I wish to acknowledge Pete Darcy, Eric Branger, and the rest of the team of professionals at Lippincott Williams & Wilkins for their assistance and support with the transformation of the first edition into its present format. I wish to thank the administrators of various schools and associations who shared their curriculum and objectives. I also thank the reviewers for their useful comments, without which it would have been difficult to modify the contents of the first edition and better meet the needs of this audience. I would also like to acknowledge the massage therapy students of Mount Royal College, Calgary, for their useful feedback and sugges- tions for improvement as they used the first edition as their textbook. I would especially like to thank Ms. Nobuko Pratt, my efficient and able research as- sistant, for the excellent job identifying and compiling relevant journal articles and for administrative assistance as I revised the book. A special thanks to the following reviewers who have made a major impact on the effec- tiveness and accuracy of the content: REVIEWERS William Rahner Desert Institute of Healing Arts John Balletto Tuscon, AZ Center for Muscular Therapy Stuart Watts William J. Ryan Academy of Oriental Medicine Department of Exercise and Rehabilitative Sciences Austin, TX Slippery Rock University of Pennsylvania Mary Sinclair Professional Institute of Massage Therapy Saskatoon, Saskatchewan Nadine Forbes Steiner Education Group Pompano Beach, FL

Figure Credits Last, but certainly not least, I wish to thank my husband and children for their encour- agement and great support. In addition to the artwork created by Dragonfly Media Group, Mark Miller Medical Il- lustrations, Kim Battista, Mary Anna Barratt, and Susan Caldwell, liberal use has been made of illustrations from the following Lippincott Williams & Wilkins sources: Agur. Grant’s Atlas of Anatomy, 10th Ed. Lippincott Williams & Wilkins, 1999. Anderson, Hall. Sports Injury Management, 2nd Ed. Lippincott Williams & Wilkins, 2000. Bear, Conner, Paradiso. Neuroscience, 2nd Ed. Lippincott Williams & Wilkins, 2000. Cipriano. Photographic Manual of Regional Orthopaedic and Neurological Tests, 2nd Ed. Lippincott Williams & Wilkins, 1991. Cohen, Wood. Memmler’s The Human Body in Health and Disease, 9th Ed. Lippincott Williams & Wilkins, 1999. Cormack. Essential Histology, 2nd Ed. Lippincott Williams & Wilkins, 2001. Daffner. Clinical Radiology, 2nd Ed. Lippincott Williams & Wilkins, 1998. Dean, Herbener. Cross-Sectional Human Anatomy. Lippincott Williams & Wilkins, 2000. Gartner H. Color Atlas of Histology, 3rd Ed. Lippincott Williams & Wilkins, 2001. Goodheart. Photoguide of Common Skin Disorders, 2nd Ed. Lippincott Williams & Wilkins, 2003. Hamill, Knutzen. Biomechanical Basis of Movement, 2nd Ed. Lippincott Williams & Wilkins, 2003. Hendrickson. Massage for Orthopedic Conditions. Lippincott Williams & Wilkins, 2002. Kendall. Muscles: Testing and Function, 4th Ed. Lippincott Williams & Wilkins, 1993. McArdle, Katch, Katch. Moore A. Essential Clinical Anatomy, 2nd Ed. Lippincott Williams & Wilkins, 2002. Moore. Clinically Oriented Anatomy, 4th Ed. Lippincott Williams & Wilkins, 1999. Oatis. Kinesiology. Lippincott Williams & Wilkins, 2003. Pilliterri. Maternal and Child Health Nursing, 4th Ed. Lippincott Williams & Wilkins, 2002.

xvi Figure Credits Porth. Pathophysiology, 6th Ed. Lippincott Williams & Wilkins, 2002. Rubin. Essential Pathology, 3rd Ed. Lippincott Williams & Wilkins, 2000. Sadler. Langman’s Medical Embryology, 9th Ed. Lippincott Williams & Wilkins, 2003. Smeltzer, Bare. Brunner and Suddarth’s Textbook of Medical-Surgical Nursing, 9th Ed. Lippincott Williams & Wilkins, 2002. Snell. Clinical Neuroanatomy. Lippincott Williams & Wilkins, 2001. Stedman’s Concise Medical Dictionary for the Health Professions, 3rd Ed. Lippincott Williams & Wilkins, 2001. Stedman’s Medical Dictionary, 27th Ed. Lippincott Williams & Wilkins, 2000. Tweitmeyer, McCracken. Coloring Guide to Human Anatomy, 3rd Ed. Lippincott Williams & Wilkins, 2001. Westheimer, Lopater. Human Sexuality. Lippincott Williams & Wilkins, 2003.

Contents CHAPTER 1 Introduction to Anatomy and Physiology .......................•• Levels of Organization—An Overview The Holistic Approach Homeostasis FEEDBACK SYSTEMS Systems of the Body Planes of Reference Anatomic Position Directional References Body Regions HEAD AND NECK TRUNK UPPER EXTREMITY LOWER EXTREMITY Body Cavities

xviii Contents Levels of Organization CHEMICAL LEVEL OF ORGANIZATION CELLULAR LEVEL OF ORGANIZATION TISSUE LEVEL OF ORGANIZATION Effects of Age on Tissue Implications for Bodyworkers CHAPTER 2 Integumentary System......................................................•• Functions of the Skin Structure of the Skin THE EPIDERMIS THE DERMIS NERVE SUPPLY TO THE SKIN BLOOD CIRCULATION IN THE SKIN Skin and Temperature Control Variation in Skin Color BLOOD FLOW AND SKIN COLOR CHANGES PIGMENTATION OF SKIN BY CAROTENE SUBCUTANEOUS LAYER, OR HYPODERMIS ACCESSORY STRUCTURES Absorption Through the Skin Microorganisms on the Skin Inflammation and Healing COMMON CAUSES OF INFLAMMATION CARDINAL SIGNS OF INFLAMMATION SYMPTOMS ACCOMPANYING INFLAMMATION RESOLUTION OF INFLAMMATION EXUDATIVE INFLAMMATION CHRONIC INFLAMMATION HEALING AND REPAIR

Contents xix Effects of Aging on the Integumentary System Integumentary System and Bodyworkers MASSAGE TECHNIQUES AND THE EFFECTS ON THE BODY EFFECT OF HEAT ON SKIN EFFECT OF COLD ON SKIN WATER AND SKIN BODY WRAPS AND SKIN SKIN LESIONS AND BODYWORKERS CHAPTER 3 Skeletal System and Joints................................................•• The Skeletal System BONE FUNCTIONS STRUCTURE AND FORMATION OF BONE BONE REMODELING PARTS OF A LONG BONE TYPES OF BONES The Human Skeleton The Axial Skeleton THE SKULL BONES OF THE FACE THE MANDIBLE THE VERTEBRAL COLUMN THE THORAX The Appendicular Skeleton PECTORAL GIRDLE AND THE UPPER LIMBS THE PELVIC GIRDLE AND LOWER LIMBS THE PELVIC GIRDLE Joints JOINT CLASSIFICATIONS STABILITY OF SYNOVIAL JOINTS MOVEMENT ACROSS THE JOINTS CLASSIFICATION OF SYNOVIAL JOINTS

xx Contents Individual Joints TEMPOROMANDIBULAR JOINT (TMJ) INTERVERTEBRAL ARTICULATION RIB CAGE ARTICULATIONS Joints of the Pectoral Girdle and Upper Limb THE STERNOCLAVICULAR JOINT ACROMIOCLAVICULAR JOINT GLENOHUMERAL JOINT THE ELBOW JOINT DISTAL (INFERIOR) RADIOULNAR JOINT MIDDLE RADIOULNAR JOINT JOINTS OF THE WRIST AND HAND THE WRIST JOINT (RADIOCARPAL JOINT) OTHER JOINTS OF THE HANDS Joints of the Pelvic Girdle and Lower Limbs SACROILIAC JOINT THE HIP JOINT THE KNEE JOINT TIBIOFIBULAR JOINT (PROXIMAL AND DISTAL) THE ANKLE JOINT AND JOINTS OF THE FOOT ARCHES OF THE FOOT Age-Related Changes on the Skeletal System and Joints The Skeletal System, Joints, and Massage CHAPTER 4 Muscular System ..........................................................................•• Muscle Tissue and Physiology of Muscle Contraction STRUCTURE OF SKELETAL MUSCLE THE MYOFILAMENT: THE SPECIALIZED PROTEINS OF MYOFIBRILS SLIDING FILAMENT MECHANISM CHARACTERISTICS OF WHOLE MUSCLE CONTRACTION MUSCLE TONE MUSCLE SPINDLES

Contents xxi TENDON ORGANS OTHER PROPRIOCEPTORS ISOTONIC AND ISOMETRIC CONTRACTIONS Muscle Energetics AEROBIC METABOLISM ANAEROBIC METABOLISM EFFICIENCY OF MUSCLE WORK MUSCLE RECOVERY MUSCLE FATIGUE MUSCLE PERFORMANCE MUSCLES AND HORMONES A Summary of the Role of CNS in Muscle Function Control Physical Conditioning EXERCISE TRAINING PRINCIPLES ADAPTATION TO TRAINING FACTORS AFFECTING RESPONSE TO TRAINING METHODS OF TRAINING EFFECT OF OVERTRAINING TRAINING DURING PREGNANCY MUSCLE ATROPHY Cardiac, Smooth, and Skeletal Muscle CARDIAC MUSCLE SMOOTH MUSCLE Muscle Terminology and Major Muscles of the Body MUSCLE TERMINOLOGY NAMES OF MUSCLES Origin and Insertion of Muscles THE AXIAL MUSCULATURE THE APPENDICULAR MUSCULATURE MUSCLES OF THE LOWER LIMB

xxii Contents Muscular System and Aging Muscular System and Massage CHAPTER 5 Nervous System ...............................................................•• Organization of the Nervous System STRUCTURE OF THE NEURON THE SYNAPSE CLASSIFICATION OF NEURONS NEUROGLIA PRODUCTION AND PROPAGATION OF IMPULSES DIFFERENCES IN PROPAGATION OF ACTION POTENTIAL IN MYELINATED AND UNMYELINATED AXONS SYNAPTIC TRANSMISSION EXAMPLES OF NEUROTRANSMITTERS ELECTRICAL SYNAPSES SUMMATION FACTORS THAT AFFECT NEURAL FUNCTION FUNCTIONAL ORGANIZATION OF NEURONS STANDARD TERMS AND GROUPING REGENERATION AND DEGENERATION OF NEURONS Sensory Nervous System SENSE ORGANS AND INITIATION OF IMPULSES CUTANEOUS RECEPTORS AN OVERVIEW OF ELECTRICAL AND IONIC EVENTS IN RECEPTORS PERCEPTION OF SENSATIONS THE SPINAL CORD, SPINAL NERVES, AND DERMATOMES ANATOMIC STRUCTURE OF THE SPINAL CORD DISTRIBUTION OF SPINAL NERVES NERVE PLEXUS REFLEXES MONOSYNAPTIC REFLEX: THE STRETCH REFLEX MUSCLE SPINDLE RECIPROCAL INNERVATION INVERSE STRETCH REFLEX

Contents xxiii POLYSYNAPTIC REFLEXES: WITHDRAWAL REFLEX THE FINAL COMMON PATH INPUT TO MOTOR NEURONS PATHWAYS OF CUTANEOUS AND VISCERAL SENSATIONS DIRECT PATHWAY OF FINE TOUCH AND PROPRIOCEPTION SENSES DIRECT PATHWAY OF PAIN AND TEMPERATURE (AND REMAINING FIBERS OF TOUCH) SENSES REPRESENTATION OF THE BODY IN THE CEREBRAL CORTEX The Brain and Brain Divisions THE CEREBRUM INTEGRATIVE CENTERS RIGHT AND LEFT HEMISPHERE SPECIALIZATIONS THE LIMBIC SYSTEM THE THALAMUS THE HYPOTHALAMUS THE BRAINSTEM: MIDBRAIN, PONS, AND MEDULLA Cranial Nerves OLFACTORY NERVE (CRANIAL NERVE I) TRIGEMINAL NERVE (CRANIAL NERVE V) FACIAL NERVE (CRANIAL NERVE VII) VESTIBULOCOCHLEAR NERVE (CRANIAL NERVE VIII) VAGUS (CRANIAL NERVE X) Control of Posture and Movement GENERAL PRINCIPLES OF THE CONTROL OF VOLUNTARY MOVEMENTS THE MOTOR CORTEX LESIONS AND MUSCLE TONE OTHER POSTURE-REGULATING SYSTEMS BASAL GANGLIA CEREBELLUM VESTIBULAR APPARATUS MOTOR SYSTEM LESIONS RETICULAR ACTIVATING SYSTEM AND AROUSAL MECHANISMS LEARNING AND MEMORY

xxiv Contents MENINGES, CEREBROSPINAL FLUID, AND ITS CIRCULATION BLOOD SUPPLY TO THE BRAIN The Autonomic Nervous System THE SYMPATHETIC DIVISION THE PARASYMPATHETIC DIVISION NEUROTRANSMITTERS OF SYMPATHETIC AND PARASYMPATHETIC DIVISIONS THE SYMPATHETIC SYSTEM AND THE ADRENAL MEDULLA GENERAL PATTERN OF RESPONSE PRODUCED BY THE SYMPATHETIC AND PARASYMPATHETIC SYSTEMS CONTROL OF AUTONOMIC FUNCTION Age-Related Changes in the Nervous System VISION HEARING TASTE AND SMELL AUTONOMIC NERVOUS SYSTEM IMPLICATION FOR BODYWORKERS Bodyworkers and the Nervous System CHAPTER 6 Endocrine System.............................................................•• General Properties of Hormones RECOGNITION OF HORMONES BY CELLS CHEMICAL STRUCTURE OF HORMONES STIMULI FOR HORMONE SECRETION CIRCULATING AND LOCAL HORMONES TRANSPORT AND DESTRUCTION OF HORMONES HORMONE ACTIONS Control of the Endocrine Glands The Endocrine Glands THE HYPOTHALAMUS THE PITUITARY GLAND (HYPOPHYSIS) THE THYROID GLAND

Contents xxv PARATHYROID GLANDS ADRENAL GLANDS PINEAL GLAND ENDOCRINE FUNCTION OF THE PANCREAS TESTIS, OVARIES, AND PLACENTA THE ENDOCRINE FUNCTION OF THE KIDNEYS THE ENDOCRINE FUNCTION OF THE HEART THYMUS DIGESTIVE TRACT THE ENDOCRINE FUNCTION OF ADIPOSE TISSUE Age-Related Changes in the Endocrine System Endocrine System and Massage STRESS AND BODYWORKERS CHAPTER 7 Reproductive System........................................................•• Genetic Sex, Fetal Development, and Puberty GENETIC SEX FETAL DEVELOPMENT PUBERTY The Male Reproductive System THE TESTIS THE VAS DEFERENS ACCESSORY GLANDS SEMEN PENIS ENDOCRINE FUNCTION OF THE TESTIS The Female Reproductive System THE OVARIES THE UTERINE TUBES (FALLOPIAN TUBES; OVIDUCT) THE UTERUS THE VAGINA THE EXTERNAL GENITALIA

xxvi Contents THE MENSTRUAL CYCLE THE PHYSIOLOGY OF SEXUAL INTERCOURSE (IN BRIEF) CONTRACEPTION (STRATEGIES FOR BIRTH CONTROL) Pregnancy DEVELOPMENT OF THE FETUS MATERNAL CHANGES IN PREGNANCY LABOR LACTATION AGE-RELATED CHANGES IN THE REPRODUCTIVE SYSTEM MASSAGE AND THE REPRODUCTIVE SYSTEM CHAPTER 8 Cardiovascular System .....................................................•• Blood FORMATION OF BLOOD CELLS RED BLOOD CELLS BLOOD TYPES WHITE BLOOD CELLS (LEUKOCYTES) PLATELETS HEMOSTASIS THE CLOTTING MECHANISM ANTICLOTTING MECHANISMS PLASMA Heart and Circulation AN OVERVIEW OF CIRCULATION FACTORS AFFECTING CARDIAC OUTPUT Blood Vessels and Circulation STRUCTURE AND FUNCTION OF BLOOD VESSELS MAJOR SYSTEMIC ARTERIES SYSTEMIC VEINS Dynamics of Blood Flow BLOOD PRESSURE PERIPHERAL RESISTANCE

Contents xxvii Regulation of the Cardiovascular System LOCAL MECHANISMS NEURAL MECHANISMS ENDOCRINE MECHANISMS COMPENSATIONS MADE BY THE CARDIOVASCULAR SYSTEM TO EFFECTS OF GRAVITY, EXERCISE, SHOCK, AND CARDIAC FAILURE Effect of Aging on the Cardiovascular System HEART BLOOD VESSELS BLOOD EFFECT OF REGULAR EXERCISE Massage and the Cardiovascular System CHAPTER 9 Lymphatic System ............................................................•• Body Fluid Compartments PHYSICAL FORCES THAT CAUSE MOVEMENT OF FLUID BETWEEN COMPARTMENTS EDEMA The Lymphatic System FUNCTIONS OF THE LYMPHATIC SYSTEM COMPONENTS OF THE LYMPHATIC SYSTEM DRAINAGE ROUTE OF LYMPH Massage and the Lymphatic System MASSAGE AND LYMPHEDEMA MASSAGE AND LOCALIZED SWELLING CANCER AND MASSAGE Immunity NONSPECIFIC IMMUNITY SPECIFIC IMMUNITY LYMPHOCYTES IMMUNIZATION ABNORMALITIES OF THE IMMUNE SYSTEM

xxviii Contents The Lymphatic System, Immunity, and Aging Basic Concepts of Health and Disease Immunity and Massage CHAPTER 10 Respiratory System...........................................................•• Function of the Respiratory System The Anatomy of the Respiratory System UPPER RESPIRATORY TRACT LOWER RESPIRATORY TRACT THE PULMONARY CIRCULATION THE LUNGS THE PLEURA Mechanics of Respiration EXTERNAL RESPIRATION RESPIRATION MUSCLES BREATHING PATTERNS, RESPIRATORY VOLUMES, AND CAPACITIES Gas Exchange TRANSPORT OF GASES Regulation of Respiration AUTOREGULATION IN TISSUE AUTOREGULATION IN LUNGS RESPIRATORY CONTROL SYSTEM OF THE BRAIN CHEMICAL CONTROL OF RESPIRATION OTHER MECHANISMS THAT CONTROL RESPIRATION Effect of Exercise on the Respiratory System Effect of Cold on the Respiratory System Effect of Aging on the Respiratory System Respiratory System and Massage

Contents xxix CHAPTER 11 Digestive System ..............................................................•• Functions of Gastrointestinal System Components of the Gastrointestinal System Walls of the Digestive Tract MUCOSA SUBMUCOSA MUSCULARIS SEROSA Peritoneum MESENTERY AND OMENTUM Movement in the Digestive Tract Factors Controlling Digestive Function An Overview of Nutrition Functions of Important Nutrients PROTEINS/AMINO ACIDS CARBOHYDRATES FAT VITAMINS OTHER NUTRIENTS Regulation of Food Intake Blood Supply to the Digestive Tract The Structure and Function of Individual Organs of the Digestive System THE MOUTH AND ASSOCIATED STRUCTURES SALIVARY GLANDS AND SALIVA PHARYNX ESOPHAGUS STOMACH SMALL INTESTINE

xxx Contents THE PANCREAS THE LIVER GALLBLADDER ABSORPTION IN THE SMALL INTESTINE THE LARGE INTESTINE Movement in the Colon and Defecation Digestion and Absorption of Food in the Gut CARBOHYDRATE DIGESTION AND ABSORPTION LIPID DIGESTION AND ABSORPTION PROTEIN DIGESTION AND ABSORPTION WATER ABSORPTION ELECTROLYTE (IONS) ABSORPTION VITAMIN ABSORPTION Metabolism CARBOHYDRATE METABOLISM LIPID METABOLISM PROTEIN METABOLISM Basal Metabolic Rate REGULATION OF METABOLIC RATE Age-Related Changes in the Gastrointestinal System ORAL CAVITY ESOPHAGUS STOMACH SMALL INTESTINE LARGE INTESTINE PANCREAS LIVER The Gastrointestinal System and Bodywork

Contents xxxi CHAPTER 12 Urinary System ..................................................................................•• Functions of the Urinary System Components of the Urinary System THE KIDNEYS Urine Formation REGULATION OF BODY FLUIDS—THE PROCESS OF CONCENTRATING AND DILUTING URINE REGULATION OF PH THE COMPOSITION OF URINE Transportation and Elimination of Urine THE URETER THE URINARY BLADDER THE URETHRA Urination or Micturition Age-Related Changes in the Genitourinary System KIDNEYS URETERS URINARY BLADDER AND URETHRA RELEVANCE TO BODYWORKERS Bodyworkers and the Urinary System

CHAPTER 1 Introduction Objectives On completion of this chapter, the reader should be able to: • Define anatomy and physiology and identify some of the subdivisions. • Identify word roots, prefixes, and suffixes and combining forms. • List the organizational levels of the body. • List the major organ systems of the body and explain the function of each system. • Describe the anatomic position. • Identify the abdominal regions and quadrants. • Identify the organs located in each abdominal region. • Define the principal directional terms and body planes. • Name the cavities of the body and identify the major organs contained in each cavity. • Differentiate intracellular, extracellular, interstitial, and intravascular body fluids. • Define homeostasis. • Identify the components of a feedback system. • Describe how a physiologic feedback mechanism maintains homeostasis. • Differentiate between positive and negative feedback mechanisms; give examples of each. • Define atoms and molecules. • Describe the different chemical reactions. • Define enzymes and explain their functions. • List the factors that affect enzyme activity. • Define pH. • Define buffers. Provide examples of buffer systems in the body. • Distinguish between organic and inorganic compounds and provide examples for both com- pound types. • Give a brief description of the structure and biologic functions of carbohydrates, lipids, proteins, and nucleic acids and provide examples. • Give a brief description of DNA structure and the genetic codes. • Give a brief description of protein synthesis regulation and the steps involved in the process. • Describe the structure of a cell and the functions of each organelle. • Describe the structure of the cell membrane. • Describe the different ways transport occurs across a cell membrane. • Define chromosomes. • Give a brief description of mitosis and meiosis. • Classify tissue. • Describe the structure and function of each tissue type; identify some locations where each type is found. • Describe and compare the different types of connective tissue. • Describe the structure of collagen. 1

2 The Massage Connection: Anatomy and Physiology • Describe the different types of cartilage and identify locations for each type. • Differentiate between skeletal, cardiac, and smooth muscle. • Describe the structure and function of nervous tissue. • Describe the inflammation process and tissue repair. • Describe the different outcomes of tissue repair. • Identify the different types of membranes and give the locations where each type may be found. • Describe the effects of aging on different types of tissue. • Describe the possible effects of massage on healthy tissue. W ith the recognition of massage as an alternative of a muscle; physiology describes how the muscle contracts. Remember that the structure of any body or complementary form of therapy, the demands is adapted to its functions; therefore, anatomy and made of the therapist are increasing. Although mas- physiology are closely related. sage is more involved with the knowledge and use of physical skills and techniques, the knowledge of Anatomy can be divided into many subtypes. Mi- anatomy, physiology, and pathology is also necessary croscopic anatomy involves structures that cannot be for the therapist to effectively use those learned mas- visualized with the naked eye. Macroscopic, or gross sage skills. The therapist is certainly not required to anatomy, considers structures that can be visualized know the field as thoroughly as medical professionals without aid. Surface anatomy involves the study of because diagnosis is not involved; however, the ther- general forms and superficial markings on the surface apist should have the knowledge to understand how of the body. Regional anatomy focuses on the super- the body functions and how different parts of the ficial and internal features of a specific area. Systemic body integrate. anatomy is the study of structures that have the same function. Developmental anatomy involves changes With this foundation, a therapist should under- that occur during the course of physical development. stand how various diseases affect specific functions Embryology is a study of changes that occur during and how to recognize those conditions in which development in the womb. Histology involves the ex- treatment may be detrimental to the client. Thera- amination of tissues, groups of specialized cells, and pists should also be able to recognize conditions that cell products that work together to perform specific may be harmful to his or her well-being. functions. Cytology involves the analysis of the inter- nal structure of individual cells. In addition, the therapist must have a thorough knowledge of various standard medical terms that are Physiology can also be divided into subtypes. Cell accepted and used in the medical field. This will help physiology relates to the study of the cell function, the therapist effectively discuss a client’s condition and systemic physiology considers the functioning with other health professionals, a situation that often of structures that serve specific needs, such as respi- occurs. The correct terminology will also help the ration and reproduction. Pathophysiology is the therapist keep up with the rapidly increasing knowl- study of how disease affects specific functions. edge in health-related fields relevant to massage. Levels of Organization—an Chapter 1 gives an overview of the organization of Overview the body and introduces basic anatomy and physiol- ogy terms. The body is made up of millions of individual units called cells. Cells are the smallest living part of the The definition of the term anatomy, meaning “cut- body. The cells, in turn, are made up of chemi- ting open,” originates from the ancient Greek. Al- cals—atoms (e.g., carbon, hydrogen, oxygen, nitro- though the study of anatomy need not involve “cut- ting,” it is the study of the external and internal AUTOPSY structures of the body and the physical relationship between the parts of the body. Anatomy answers the Autopsy is the examination of all of the organs and tissues questions: What? Where? Physiology, also of Greek of the body after death. Autopsies are of value because origin, is the study of the functions of the various they often determine the cause of death or reveal disease parts of the body. It answers the questions: Why? or structural defects. They can be used to check the effec- How? For example, anatomy describes the location tiveness of a particular drug therapy or surgery. Think It Through. . . Would you consider massage therapy to be alternative therapy, complementary therapy, or both?

Chapter 1—Introduction 3 gen, and phosphorus), molecules, and compounds Homeostasis (proteins, carbohydrates) organized in different ways to form the structures inside the cell. A col- Traditionally, the body has been divided into many lection of cells having the same function is called systems, according to specific functions. The ultimate tissue. For example, a collection of cells that pro- purpose of every system, however, is to maintain a duce contraction is called muscle tissue. Different constant cell environment, enabling each cell to live. tissues that are grouped together and perform the Fluid surrounds every cell of the body, and all sys- same function are called organs. For example, the tems are structured to maintain the physical condi- stomach, which helps with food digestion, is made tions and concentrations of dissolved substances in up of muscle tissue that helps move the food, con- this fluid. The fluid outside the cell is known as the nective tissue that binds the muscle tissue, blood extracellular fluid (ECF), and the fluid inside the vessels and glands, epithelial tissue that lines the cell is known as intracellular fluid (ICF) (see Figure inside of the stomach, and nervous tissue that reg- 1.2). The extracellular fluid inside the blood vessel is ulates the movement and secretion of glands. Or- known as the intravascular fluid, or plasma. The gans with the same function are grouped together fluid outside of the cells and the blood vessels is as systems; an organ may be part of more than known as the interstitial fluid. Because the intersti- one system. For example, the respiratory system in- tial fluid surrounds the cells, it is known as the inter- cludes organs that help deliver oxygen to the body; nal environment; the condition of constancy in the the reproductive system includes organs that help internal environment is called homeostasis. In short, the organism reproduce. The body may be consid- all systems maintain homeostasis by regulating the ered to have six different levels of organization— volume and composition of the internal environment. chemical, cellular, tissue, organ, and systemic (see Figure 1.1) The highest level of organization— Each system continuously alters its active state to the organismal level—is the living body. maintain homeostasis. The maintenance of homeo- stasis can be compared to the working of a baking The Holistic Approach oven. When the temperature is set, the heating ele- ment (the effector) is switched on—indicated by a Although it is easier to teach and learn anatomy and red light—to heat the oven. When the desired tem- physiology by dividing the body into organs and sys- perature is reached, the heating element is switched tems, it has to be understood that the body is com- off and the light goes out. When you open the oven plex and highly integrated. Each system is interde- door (without switching off the oven, of course) to pendent and works together as one—THE BODY. In check the food that is baking, the light comes on The Life Application Study Bible, (Life Application again—have you noticed that? When you open the Study Bible. Tyndale House Publishers, 1997:I oven door, the heat escapes and the temperature Corinthians 12:12-27.) the analogy of the human drops slightly. This drop in temperature is detected body is used in a different context; however, it aptly (receptor) and conveyed to the thermostat (the con- describes the working of the body: “. . . the body is a trol center) in the oven and the heating element is unit, though it is made up of many parts; and though switched on. all its parts are many, they form one body . . . if one part suffers, every part suffers with it; if one part is Similarly, the body has various detectors to detect honored, every part rejoices with it.” changes in specific elements. Let’s take, for example, the oxygen content in the blood. If the detectors (re- What happens to one tissue affects the whole body ceptors) find the level of oxygen becoming lower, they and what happens to the body affects all of its parts. It stimulate the system(s) that bring oxygen into the is this holistic concept that alternative/complementary body—the respiratory system works harder until the therapy, of which massage is one, adopts. To extend oxygen level reaches the normal range. this further, the manipulation of soft tissue in one area potentially affects the whole body. Imagine many similar detectors located all over the body—monitoring calcium, hydrogen, and The best learning approach for anatomy and phys- sodium levels; volume of blood; blood pressure; hor- iology is to view the body “holistically.” Although mone levels; and body temperature. Can you picture ideal, the body is too complex for the beginning stu- each of these regulators monitoring specific elements dent to fully appreciate how the different parts inte- and bringing about an appropriate action or change grate. This book, therefore, addresses individual sys- in various systems—all at the same time! You expect tems or parts of the body with the hope that, in the chaos. Instead, the body is orchestrated so beauti- end, the entire picture will fall into place. fully that all systems work in harmony with one aim—to maintain homeostasis. When a person is ill, therefore, the body must be treated as a whole and

4 The Massage Connection: Anatomy and Physiology 2 Cellular level 1 Chemical level Molecule (DNA) Atoms Cardiac muscle cell 3 Tissue level 6 Organism level Heart Cardiac tissue Aorta 4 Organ level Inferior vena cava 5 System level Heart Circulatory system FIGURE 1.1. Levels of Organization of the Body

Chapter 1—Introduction 5 Total body fluids: 40 liters ceptor in the body monitors the variable and sends input to the control center in the brain. The control Plasma Red blood cells center determines the normal range of values. De- volume: volume: pending on the change in the level of the variable, the 3 liters 2 liters control center sends out messages to structures that help nullify this effect. These structures are known as Interstitial the effectors. volume: 10 liters When you stand up from a lying down position, for example, blood pools in your lower limbs and your Extracellular Intracellular blood pressure drops as a result of the effects of grav- volume: volume: ity. This drop in pressure is detected by receptors lo- 15 liters 25 liters cated in the blood vessels walls in your neck. The re- ceptors convey the change in blood pressure to the (Blood volume: 5 liters) brain (control center) via the nerves, and the brain FIGURE 1.2. Body Fluid Compartments sends messages to the blood vessels (effectors) to constrict. With constriction, the volume decreases not as individual systems. Massage therapy, to bring and the pressure inside the blood vessels increases, about complete healing, should treat the entire per- bringing the blood pressure back to the normal son and not only the diseased part or state. range. Here, the feedback loop has nullified the change that occurs. This feedback mechanism is FEEDBACK SYSTEMS known as negative feedback (see Figure 1.3A). The sequence of events that result in maintaining Rarely, changes in the variable are enhanced. In homeostasis is known as a feedback system. In a such a feedback loop, change produced in the vari- feedback system, a particular variable is constantly able is conveyed to the control center, and the control monitored. Changes are instituted to decrease or in- center intensifies the change. This feedback mecha- crease the level of the variable to maintain the level nism is known as positive feedback (see Figure within the normal range. Numerous feedback sys- 1.3B). For example, at the time of labor, the head of tems are involved in the regulation of the internal en- the baby descends and stretches the cervix (the lower vironment. The variable in question is known as the end of the uterus). The stretch is detected by recep- controlled condition. Any factor that changes the tors and conveyed to the pituitary gland located in level of the variable is known as the stimulus. The re- the brain. The pituitary gland secretes a hormone (oxytocin) that produces uterine contractions. The uterine contractions push the baby down, further stretching the cervix. This process continues until the baby is born and the cervix is no longer stretched. Be- cause positive feedback reinforces the change, it is not a feedback mechanism commonly used by the body. When all the components of every feedback system work well and homeostasis is maintained, the body remains healthy. Regulatory Mechanisms Systems of the Body Try this simple experiment. Hold your breath for one This book, for convenience, divides the body into the minute and then start breathing. You will notice that you integumentary, skeletal, muscular, nervous, car- breathe more rapidly for a short while after you stop diovascular, lymphatic, respiratory, endocrine, re- holding your breath. This increase in breathing is caused productive, digestive, and urinary systems (see by regulatory mechanisms. The detectors, which noticed Figure 1.4). At times, the skeletal and muscular are that the carbon dioxide and hydrogen ion levels were in- considered together as musculoskeletal system. creasing in your body, conveyed that information to the control center in the brain, which, in turn, made your The integumentary (skin) system includes the respiratory muscles (effectors) work more actively. When skin and all of its structures, such as sweat glands, the carbon dioxide and hydrogen ion levels reach the nails, and hair. The major function of this system (see normal range, it is detected by the receptors and con- Figure 1.4A) is to protect the body from environmen- veyed to the control center, which, in turn, reduces the tal hazards and to maintain core temperature. For an activity of the respiratory muscles.

6 The Massage Connection: Anatomy and Physiology At the onset of labor, uterine contractions push head (or body) of baby into the cervix Results in stretch of cervix Stimulus Increases blood Receptors pressure Stretch detected by nerve cells in cervix Receptors Nerve Input impulses Baroreceptors in aorta and carotid arteries Control Center Nerve Input Brain Positive feedback: impulses (Pituitary Increased stretching of gland) cervix causes release of Control Center Oxytocin more oxytocin, which Output results in more stretching of cervix Brain Negative feedback: Effectors The decrease in blood pressure negates the Oxytocin produces more forceful contractions original change in of the uterus blood pressure Nerve Output impulses Effector Resultant descent of baby stretches the cervix more A decrease in heart rate Interruption of cycle: and force of contraction Birth of baby decreases A decreases blood pressure stretching of cervix, breaking the positive B feedback cycle FIGURE 1.3. A, Negative Feedback Mechanism; B, Positive Feedback Mechanism Flowchart for Figure 1.3A: Standing up after lying down - ↔ blood pools in leg - ↔ blood pressure decreases in blood vessels in neck (controlled condition) --- ↔ Receptors in walls of blood vessels of neck detect change and con- vey change to -- ↔ brain (control center) -- ↔ brain stimulates smooth vessels in blood vessels to contract -- ↔ blood vessels constrict and blood pressure increases --- ↔ blood pressure returns to normal (change nullified) (please illustrate flowchart as in diagram) Flowchart for Figure 1.3B: During labor, baby’s head descends and stretches the cervix - ↔ stretch of cervix detected by receptors - ↔ change conveyed to the pituitary gland in brain -- ↔ pituitary gland se- cretes the hormone oxytocin into the blood -- ↔ hormone conveyed by blood to the uterus -- ↔ hormone stimulates uterine muscles to contract - ↔ baby pushed out - ↔ birth of baby interrupts positive feedback cycle

Chapter 1—Introduction 7 example of how skin maintains homeostasis, con- and allow movement in various planes (joints). In ad- sider the effects of an increase in atmospheric tem- dition, this system protects tissue and organs—for ex- perature. The skin possesses sensors (nerve recep- ample, the ribs protect the lungs and heart, which are tors) that detect temperature change. When a rise in located in the chest. Minerals, including calcium, are temperature is detected, the network of blood vessels deposited in the bones and are mobilized when the in the skin, aided by the nervous system, dilate and blood levels of these minerals are lower than the nor- more blood reaches closer to the surface of the body mal range. Different parts of the bones also manu- where heat can be removed by conduction. The sweat facture blood cells. glands increase production, and the body is cooled by sweat evaporation until body temperature reaches The muscular system (see Figure 1.4C) is respon- normal values. Other skin functions include manu- sible for any form of movement. It includes all the facturing vitamin D and eliminating waste products. muscle tissue of the body. The skeletal, cardiac, and smooth muscle are three types of muscle tissue. This The skeletal system (see Figure 1.4B) comprises system allows the organism to move in the external the bones, bone marrow, and joints of the body. The environment. In addition, internal muscles help skeletal system’s major functions are to support the move blood inside the body (e.g., the heart). The body, provide an area for muscle attachment (bones), blood volume in any region can be altered by muscle Epidermis and Hair Skull associated glands Supporting bones Upper limb (scapula and collarbone) bones Sternum Ribs Cartilage Vertebrae Sacrum Fingernail Lower limb Supporting bones bones (hip) AB FIGURE 1.4. Systems of the Body. A, Integumentary; B, Skeletal (continued)

8 The Massage Connection: Anatomy and Physiology Central nervous system: Brain Spinal cord Axial Peripheral muscles nervous system: Peripheral nerves Appendicular muscles CD FIGURE 1.4., cont’d Systems of the Body. C, Muscular; D, Nervous contractions, which narrow or dilate the vessel, in the and your muscles shiver (rapid contraction and re- blood vessels walls. Muscles in the tube walls of the laxation), produces heat. respiratory tract alter the size of the tubes. Food is moved down the gut by the contraction and relax- The organs of the cardiovascular system (see Fig- ation of muscles. Urine is expelled from the body by ure 1.4E) are responsible for the circulation of blood. contraction of the muscles of the urinary bladder. This system includes the heart, blood vessels, and the The process of muscle contraction also produces heat blood. It helps transport oxygen, nutrients, and hor- and helps maintain body temperature. mones, among others, throughout the body to vari- ous tissue, according to the needs of the tissue. Con- The nervous system (see Figure 1.4D) consists of versely, it carries waste products from the tissue to structures that respond to stimuli from inside and other areas for excretion. outside of the body, integrating the sensed stimuli and producing an appropriate response. Nervous sys- The lymphatic system (see Figure 1.4F) consists of tem structures include the brain, the spinal cord, the lymph vessels, lymph nodes, and lymphoid tissue in nerves, and the supporting tissue. The nervous sys- such areas as the tonsils, spleen, and thymus. It is re- tem coordinates the activities of all other organ sys- sponsible for defense against infection and disease and tems. For example, the nervous system senses the to help remove excess water from the tissue spaces. change in temperature when you enter a cold room and, by making the hair on your arms stand on end The respiratory system (see Figure 1.4G) works closely with the cardiovascular system and includes the nose and nasal cavities and the pharynx, larynx,

Chapter 1—Introduction 9 Lymph node Axillary nodes Cisterna chyli Thoracic duct Cubital nodes Lymphatic Heart vessels Iliac nodes Artery Vein Popliteal nodes Superficial Capillaries inguinal nodes Lymphatic vessels EF FIGURE 1.4., cont’d Systems of the Body. E, Cardiovascular; F, Lymphatic (continued) trachea, bronchial tubes, and lungs. Although the res- thyroid, and adrenal glands and endocrine part of piratory system brings oxygen to the site where ex- the pancreas, ovary, and testis. The blood carries change can take place (i.e., between air and the these chemicals to other receptive organs and, in blood), it is the cardiovascular system that circulates turn, produces change. For example, during a preg- the blood and enables the tissue access to the oxygen. nant woman’s labor, the hormone oxytocin is se- The respiratory system also allows carbon dioxide, a creted by an endocrine organ in the brain (pitu- byproduct of metabolism, to be released in the air. itary) and is carried by the blood to the uterus. The uterus, in turn, responds by contracting. The endocrine system (see Figure 1.4H) works closely with the nervous system. Through the use The reproductive system (see Figure 1.4I) is re- of hormones, it produces long-term changes in var- sponsible for the propagation of the species and in- ious organ and system activities. Hormones are the cludes organs, such as the ovary and testis, that man- chemicals secreted by the organs of the endocrine ufacture sperms or eggs and secrete sex hormones. system, which include the pituitary, thyroid, para- Other organs include the fallopian tubes and uterus

10 The Massage Connection: Anatomy and Physiology Pineal gland Parathyroid glands Pituitary gland Nasal cavity Thyroid gland Adrenal gland Pharynx Larynx Trachea Thymus Bronchi Lung Pancreas G H Testis (male) Ovary (female) FIGURE 1.4., cont’d Systems of the Body. G, Respiratory; H, Endocrine in women and the vas deferens and accessory glands body is dehydrated, this system helps conserve water in men. The hormones, together with the genetic and salt. In addition, together with the respiratory make up, is responsible for the male or female char- system, the urinary system maintains the body fluid acteristics of the body. pH. Its structures include the kidney, ureter, urinary bladder, and urethra. The digestive system (see Figure 1.4J) also works in coordination with the cardiovascular system. Re- Planes of Reference sponsible for breaking down food into a form that can be used by the body, the cardiovascular system To study the relationship of one structure to the other carries the nutrients to the needed tissue. The diges- or to accurately explain its position, certain standard tive system includes the mouth, pharynx, esophagus, planes of references are used. Three planes are de- stomach, and small and large intestines. The urinary system (see Figure 1.4K) eliminates excess water, salts, and waste products. When the

Seminal vesicles Mammary glands Prostate gland Ductus deferens Uterine tube Urethra Ovary Epididymus Uterus Testis Vagina Penis External genitalia I Scrotum Parotid salivary gland Kidney Mouth Pharynx Submandibular and Esophagus sublingual salivary Stomach glands Ureter Liver Pancreas Urinary Gallbladder bladder Large Urethra intestine Small intestine K Rectum FIGURE 1.4., cont’d Systems of the Body. I, Reproductive; J, Digestive; K, Urinary

12 The Massage Connection: Anatomy and Physiology scribed here. The sagittal plane runs from front to Anatomic Position back, dividing the body into right and left parts. The coronal or frontal plane runs from left to right, di- Because the body can move in different ways, it is dif- viding the body into front and back portions. The ficult to describe the position of a structure without transverse or horizontal plane runs across the body, agreeing on a standard body position. This standard dividing it into top and bottom portions. These position is called the anatomic position. All struc- planes help to orient the position of studied structure tures are described in relationship to this position. In (see Figure 1.5). the anatomic position, the body is erect, with the feet parallel to each other and flat on the floor; the arms Superior are at the sides of the body, with the palms of the hands turned forward and the fingers pointing Frontal Sagittal straight down. The head and eyes are directed for- ward (see Figure 1.6). Directional References Posterior Medial In the anatomic position, a structure is described as superior/cranial or cephalic when it lies toward the Transverse Anterior head, or top, and inferior or caudal when it lies to- Lateral ward the bottom, or away from the head (Figure 1.6). For example, the tip of the nose is superior to the lips; the chin is inferior to both. A structure lying in front of another is anterior or ventral. A structure lying behind another is posterior or dorsal. For example, the ear is posterior to the cheek, and the cheek is an- terior to the ear. Those structures lying closer to an imaginary line passing through the middle of the body in the sagit- tal plane are said to be medial, while those away from the middle are lateral. For example, my belly button will always be medial to my widening waist- line. A structure lying away from the surface of the body is considered to be deep or internal, while a structure closer to the surface is considered superfi- cial or external. For example, the skin is superficial to the muscles; however, the bone is deep to the mus- cles. Proximal describes structures closer to the trunk (chest and abdomen) and distal describes structures away from the trunk. For example, the el- bow is proximal and the finger is distal to the wrist. Inferior Body Regions FIGURE 1.5. Planes of Reference The body is divided into many regions (see Figure 1.7). Knowledge of these regions helps health care professionals identify different areas of the body. Be- cause each region is related to specific internal or- gans, problems in internal organs often present as pain or swelling in these regions. For easy identifica-

Chapter 1—Introduction 13 Cranial Medial cephalic Lateral superior Proximal Anterior Posterior Ventral Dorsal Distal Caudal inferior FIGURE 1.6. Anatomic Position and Directional References tion, the major body regions are also shown in the scapular because it is the location of the bone photographs. Please refer to Figure 1.7. The major scapula. body regions are the head, neck, trunk, upper ex- tremity, and lower extremity. The abdomen is the region below the chest. The belly button (navel, or umbilicus) is located in the HEAD AND NECK center of the abdomen. The pelvic region is the low- ermost part of the abdomen and includes the pubic The head is divided into the facial region, which in- area and the perineum (the region containing the ex- cludes the eyes, nose, and mouth and the cranial re- ternal genitalia and the anus). The lower back area is gion—the top and back of the head. The neck, also known as the lumbar region, and the large hip area known as the cervical region, is the area that sup- is known as the buttock or gluteal region. The low- ports the head. Specific areas of the face are referred ermost, central region of the back is called the sacral to by different terms. The forehead region, frontal; region. To locate and relate pain and other problems eye, orbital; ear, otic; cheek, buccal, nose, nasal; of the organs lying inside, the abdomen has been di- mouth, oral; and chin, mental. vided into many subregions. TRUNK The abdomen is often divided into four regions— described as the right upper, left upper, right lower, The trunk refers to the combination of the chest and and left lower quadrants (see Figure 1.8). At times, the abdomen. The chest is also known as the thorax the abdomen is divided into nine regions, drawing or thoracic region and includes the mammary area two vertical imaginary lines just medial to the nipples (the region around the nipples), the sternal region and two horizontal lines, one at the lower part of the (the area between the mammary regions), the axil- rib cage and one joining the anterior prominent part lary or armpit region and, posteriorly, the vertebral of the hip bones. The nine regions (on the right) are region. The shoulder blade region is referred to as the right hypochondriac, right lateral or lumbar, and right inguinal or iliac (lowermost region on the right); (in the middle) epigastric, umbilical, and hy-

14 The Massage Connection: Anatomy and Physiology Head (cephalic): Forehead (frontal) Skull (cranial) Eye (orbital) Face (facial) Chin (mental) Cheek (buccal) Base of skull Head (cephalic) Ear (otic) (occipital) Neck (cervical) Neck (cervical) Nose (nasal) Mouth (oral) Shoulder Armpit (acromial) (axillary) Chest Breastbone Arm (thoracic) (sternal) Shoulder blade (brachial) (scapular) Front of Breast Upper elbow (mammary) Spinal column limb (antecubital (vertebral) or cubital) Navel Back (dorsal) Forearm (umbilical) Back of elbow Loin (lumbar) (ante- (olecranal) brachial) Abdomen Trunk Hip (coxa) Wrist (carpal) Groin (inguinal) Palm (palmar) Pelvis Thigh (femoral) Hand Between Back of hand Fingers (manual) hips (dorsum) (digital or (sacral) phalangeal) Pubis (pubic) Lower Buttock limb Anterior surface (gluteal) of knee (patellar) Shin Hollow behind knee Leg (crural) (popliteal) Foot (pedal): Calf (sural) Ankle (tarsal) Toes (digital Top of foot Sole (plantar) and phalangeal) (dorsum) B Heel (calcaneal) A FIGURE 1.7. Body Regions. A, Anterior view; B, Posterior view pogastric regions; (on the left) left hypochondriac, the back of the hand is the dorsum. The fingers are left lateral, and left inguinal or iliac regions (low- known as the digital or phalangeal region. ermost region on the left). LOWER EXTREMITY UPPER EXTREMITY The lower extremity is divided into the thigh, knee, The upper extremity is divided into the deltoid, leg, and foot regions. The upper part of the extrem- acromial or shoulder region, brachium or upper ity—the thigh—is known as the femoral region. The arm, antebrachium or forearm, and manus or front of the knee is the patellar region and the back hand regions. Between the upper arm and forearm is of the knee (similar to the front of the elbow) is called the elbow or cubital region. The front of the elbow is the popliteal fossa. The anterior part of lower leg is known as the cubital fossa. If you have had blood known as the crural region. The shin is the bony taken, it is likely that the needle was introduced into ridge that can be felt in the anterior part of the lower the blood vessel in the cubital fossa. This region is leg. The prominent, posterior, muscular part of the also known as the antecubital region. The back of lower leg is the calf or sural region. The joint be- the elbow is the olecranal region; the wrist is the tween the leg and foot is the ankle. Because the an- carpal region; the front of the hand is the palm, and kle is the location of the tarsal bones, this region is

Chapter 1—Introduction 15 also referred to as the tarsal region. The posterior cavity extends from the diaphragm into the pelvis. part of the foot is the heel or calcaneal region. The The abdominopelvic cavity can be divided into the part of the foot that faces the ground is the sole, or abdominal and the pelvic cavity. The major organs plantar surface, of the foot. The superior surface is in the abdominal cavity are the liver, gallbladder, referred to as the dorsum of the foot. The fingers of stomach, small and large intestines, pancreas, kid- the hands and toes of the foot are called digits. neys, and spleen. The uterus (in women), the urinary bladder, and the lower part of the large intestines are Body Cavities some organs that lie in the pelvic cavity. Although massage is given on the surface of the body, Levels of Organization it affects the structures located deep inside the body. If an imaginary cut is made in the sagittal plane to There are many ways to view the human body. Each look inside the body, many confined spaces or body view gives a different perspective on how the makeup cavities containing the organs will be seen (see Figure of the body and how the body works. It is similar to 1.9). Posteriorly, the brain and the spinal cord lie in viewing a flower. We can look at a flower’s colors, the cranial and vertebral, or spinal cavities, respec- with its green calyces and colorful petals, or we can tively. The cranial and vertebral cavities are continu- view it’s shape (the shape of it’s petals or how they are ous with each other. arranged) or we can consider the flower’s smell. We can pull the flower apart and view the individual Anteriorly, in the chest, is the thoracic cavity. In- parts. To go further, we can put the flower under a side the thoracic cavity, the two lungs lie in the magnifying glass and scrutinize the pollen. If we are pleural cavity and the heart lies in the pericardial really curious, we can take it to a laboratory and an- cavity. The thoracic cavity is separated from the ab- alyze the flower’s chemical makeup. So many differ- dominopelvic cavity below by the diaphragm. This Liver Stomach Spleen Right Epigastric Left Right Left hypo- region hypo- upper upper chondriac chondriac quadrant quadrant region Umbilical region (RUQ) (LUQ) region Right Left Right Left lumbar Hypogastric lumbar lower lower region (pubic) region region quadrant quadrant (RLQ) (LLQ) Right Left inguinal inguinal Small (iliac) (iliac) intestine region region A Large B Appendix Urinary bladder intestine FIGURE 1.8. Abdominal Regions. A, Anterior view showing nine abdominopelvic regions; B, Anterior view showing abdominopelvic quadrants

16 The Massage Connection: Anatomy and Physiology FIGURE 1.9. Body Cavities. A, Right lateral view; B, Anterior view ent ways—each giving a different view and perspec- resulting in red cells that become sickle-shaped and tive. break up easily. The final outcome—less red cells, less oxygen available to the cells—the patient has difficulty Similarly, for a full understanding of the human performing normal, day-to-day activities. All because body, we can study it in many ways. Here, we choose to of a slight change in the protein structure in hemo- view the organization of the body at the chemical level, globin. cellular level, tissue level and, finally, the systemic level. More time will be spent at the systemic level, Water, which makes up 50–60% of body weight, with each system being addressed as one chapter. has properties that are used to cool the body by evap- oration. Water is the medium in which ions dissolve CHEMICAL LEVEL OF ORGANIZATION and cells float. The acidity and alkalinity of this medium determine how well the various chemical re- Although a therapist seems to work at the systemic actions of the body occur. Therapists use water prop- level, the benefits of therapy are a result of changes erties to their advantage. Water is used for heat and produced at the chemical and cellular levels. Diseases, cold application. During rehabilitation, water exer- although they produce symptoms such as pain, fever, cise has been found to be beneficial. Knowledge of and edema, are actually caused by dysfunction at the the body at the chemical level and the chemical prop- cellular and chemical levels. Small changes in chemi- cal makeup can have serious effects. For example, in ELECTRICITY AND IONS IN THE BODY a disease known as sickle cell anemia, the protein in the hemoglobin molecule is slightly different from The detrimental effects of lightening and electric shock normal. This small change has drastic effects on the are a result of the presence of ions in the internal envi- properties of hemoglobin. The hemoglobin in sickle ronment. The ions conduct electricity easily. cell anemia, unlike normal hemoglobin, changes into a more solid form in an environment with less oxygen,

Chapter 1—Introduction 17 erties of water and other common substances are, other words, on their atomic number. Elements are therefore, beneficial to therapists. substances that cannot be split into simpler sub- stances by ordinary chemical means. (An atom is the The Atom smallest unit of matter that has the properties and characteristics of elements.) There are 92 elements in At the chemical level, the smallest unit of matter is the nature. As a standard, each element is given a sym- atom (see Figure 1.10). All living and nonliving things bol. Many symbols are connected to their English are made up of atoms. The characteristics of the each names, while other symbols to their Latin names. substance result from the types of atoms involved and The symbols and percentage of body weight for thir- how they are combined. An atom is made up of three teen of the most abundant elements in the human different types of particles—protons, neutrons, and body are given in Table 1.1. These elements are electrons. Protons carry a positive (ϩ) electrical mostly combined with other elements (discussed charge; neutrons have no charge; and electrons carry a later). Note that the elements oxygen, carbon, hydro- negative (-) charge. The protons and neutrons are al- gen, and nitrogen contribute to more than 90% of most the same size and mass, while the electrons are body weight. In addition to these elements, the body much lighter. Hence, the weight of the body is equal to has minute quantities of other elements (trace ele- all the neutrons and protons combined. ments), such as silicon, fluorine, copper, manganese, zinc, selenium, and cobalt. Normally, because positive charges attract nega- tive charges, an atom carries an equal number of pro- Isotopes tons and electrons. The number of protons in an atom is known as the atomic number. For example, The atoms of the same element may have different a hydrogen atom has an atomic number of 1, mean- numbers of neutrons in the nucleus. Although this ing that it has one proton and one electron. The pos- difference in number does not affect the property of itively charged proton is usually in the center, with the atom, the weight of the atoms may differ (Re- the nucleus and the negatively charged electron member, neutrons are of the same mass and size as moving around it in an orbit referred to as the elec- protons.). Hydrogen, for example, may have a proton tron shell. and no neutrons or one neutron or two neutrons in the nucleus. The atoms of an element that has a dif- At times, the electrons may not equal the number ferent number of neutrons in the nucleus are known of protons in an atom. In this case, the chemical may as isotopes. Isotopes are referred to by the combined have more positive charges or more negative charges. They then tend to attract or repel other chemicals, Table 1.1 depending on their charges. This is the basis for the movement of an electrical impulse down the nerves. The Name and Body Weight Percentage of the Elements in the Body All atoms are assigned to groups called elements, based on the number of protons they carry or, in Element Symbol Body Weight (%) (Atomic Number) Proton Neutron Electron Oxygen (8) O 65 Carbon (6) C 18.6 Hydrogen (1) H Nitrogen (7) N 9.7 Calcium (20) Ca 3.2 Phosphorus (15) P 1.8 Potassium (19) K 1.0 Sodium (11) Na 0.4 Chlorine (17) Cl 0.2 Magnesium (12) Mg 0.2 Sulfur (16) S 0.06 Iron (26) Fe 0.04 Iodine (53) I 0.007 0.0002 FIGURE 1.10. Representation of the Structure of an Atom

18 The Massage Connection: Anatomy and Physiology number of protons and neutrons (i.e., mass num- tron to fill the level. In this way, atoms with outer en- ber). The mass number is the number of protons and ergy levels that are not full gain, loose, or share elec- neutrons in an atom. In the above example, hydrogen trons to fill the outer energy level. This interaction in- with one proton is hydrogen-1 (1H); with one proton volves the formation of chemical bonds that hold and one neutron, hydrogen-2 (2H); and with one pro- the interacting atoms together, maintaining stability. ton and two neutrons, hydrogen-3 (3H). Atoms with full outer shells are stable—they do not take part in these reactions—and are said to be inert. Some of the isotopes of certain elements contain nuclei, which spontaneously emit subatomic parti- When atoms are held together by chemical bonds, cles known as radioisotopes. Radioisotopes are said the property of this “particle” is different from that of to be radioactive. These emissions can be dangerous the individual atoms. Water, for example, forms by as they can damage or destroy cells and exposure to bonding two hydrogen atoms and one oxygen atom. these emissions increases the risk of cancer. In medi- The product (water) has completely different proper- cine, radioisotopes are used for medical imaging and ties than hydrogen or oxygen. A chemical structure destroying cancerous cells. formed with two or more elements is referred to as a compound—a substance that can be broken down Electrons, Energy Levels, and Chemical Bonds into its elements by ordinary chemical means. When atoms held together by bonds share electrons, the re- Generally, atoms have the same number of protons sulting substance is called a molecule. A molecule and electrons (an equal number of positive and nega- may have atoms of the same element or of different tive charges) and are considered electrically neutral. elements. Even when the protons and electrons in an atom When atoms are bonded together, the resulting are equal, not all electrons can orbit in the same elec- substance is denoted by a molecular formula. The tron shell. Each electron shell can hold only a specific formula indicates the involved elements by their number of electrons. For example, the first shell chemical symbol. The number of each element in- (closest to the nucleus) can hold two electrons; the volved in forming the molecule or compound is de- second shell, eight electrons; the third shell, eight noted, in subscript, beside the element. For example, electrons; the fourth shell, 18 electrons, and so on. water is made up of two hydrogen atoms and one oxy- Imagine a circular theatre, with a stage in the center gen atom. The molecular formula for water is H2O. and chairs arranged in successive circular rows. Not all of the audience can sit in the first row. If there are Chemical Bonds only a few people, even the first row may not get filled. If there are more people in the audience, the Atoms can interact in three ways; therefore, there are first row gets filled and may spill over to the second three types of chemical bonds—ionic bonds, cova- row. Depending on the number of people, the second lent bonds, and hydrogen bonds. row may or may not get filled. Similarly, there are many electron shells (referred to here as energy lev- Ionic Bonds els) in an atom. The first energy level can have only two electrons in its orbit, and the second level can Some atoms may lose or gain an electron when bond- have only eight. The number of electrons in the en- ing with another atom. In the first case, this atom has ergy level affects the property of the atom. Atoms one electron less than the number of protons, mean- with energy levels that are not full react with other ing that there are more positive than negative atoms and try to fill the level. For example, the hy- charges. This atom is referred to as a cation (posi- drogen atom has an atomic number of 1 (one proton and one electron). Because the first energy level is CHEMICAL REACTIONS lacking one electron, it tries to attract another elec- Chemical reactions are denoted in a standard manner. RADIOACTIVE EMISSIONS e.g., A ϩ B → AB By carefully directing emissions on cancerous areas, ra- dioactive isotopes are used to kill cancerous cells. This is The plus (ϩ) sign denotes the two chemicals that react. The referred to as radiation therapy. arrow points in the direction of the chemical that has been formed. Arrows that point in both directions indicate the re- Exposure to radioactive emissions is dangerous, as it action is reversible and can proceed in both directions. can also destroy rapidly multiplying living cells. For this reason, pregnant women should ensure that they are not A superscript plus (ϩ) sign indicates the positive elec- exposed to radiation as it may affect the developing fetus. trical charge of the ion and the superscript minus (-) sign indicates a negative charge.

Chapter 1—Introduction 19 METABOLITES AND NUTRIENTS Atom Electron Ion Na donated Metabolites are molecules synthesized or broken down + inside the body by chemical reactions. Nutrients are es- sential elements and molecules obtained from the diet Na that are required by the body for normal function. SALT Sodium: 1 valence electron A salt is an ionic compound consisting of any cation other Atom Ion than a hydrogen ion and any anion other than a hydrox- ide ion. This means that, in chemistry, the term salt does Electron - not imply table salt as it does in the kitchen. accepted tively charged). In the second case, this atom gains Cl Cl an electron and has more electrons than protons, meaning that there are more negative charges than Chlorine: 7 valence electron positive charges. This atom is referred to as an an- ion. Both cations and anions, with their unequal + - number of protons and electrons, are known as ions. Ions are denoted by their chemical symbol, with pos- Na Cl itive or negative signs given in superscript. For ex- ample, sodium ion is represented as Naϩ; chlorine as Ionic bond in sodium chloride (NaCl) Cl-. Being positively charged, cations attract anions and vice versa. This type of bonding is known as Packing of ions in a sodium chloride crystal ionic bonds. Ionic bonds and ions are especially im- portant in nerve conduction and brain activity. FIGURE 1.11. Representation of Ionic Bond Formation (e.g., sodium chloride [table salt]) The formation of salt—table salt is a good example (see Figure 1.11). The chemical name of table salt is Covalent Bonds sodium chloride (NaCl); it is made up of sodium and chlorine. Sodium has an atomic number of 11. This In some cases, atoms share their electrons rather means that it has 11 protons (and 11 electrons) to be than gain or lose them. Such bonds are known as co- neutral. Of the eleven electrons, two occupy the first valent bonds (see Figure 1.12). The resultant chemi- energy level and eight occupy the second energy level cal is termed a molecule. A good example is the ele- and fill it. The remaining one electron (2 ϩ 8 ϭ 10) or- ment hydrogen. Hydrogen has an atomic number of bits alone in the third energy level. Because the outer 1 (i.e., 1 proton and 1 electron). However, the outer energy level is not full, the sodium atom is reactive and tends to donate its electron to another atom. Chlorine has an atomic number of 17. This means it has 17 protons and 17 electrons, making it neutral. Of the electrons, two occupy the first energy level, eight occupy the second level, and seven occupy the outer level. One more electron will fill its outer energy level; chlorine has a tendency to attract an electron. By ionic bond, sodium and chlorine come together to satisfy each other’s needs. Sharing electrons, the positively charged sodium is attracted to the nega- tively charged chlorine and they stay together to form the compound sodium chloride—table salt. When sodium chloride is dissolved in water, the ions sepa- rate—ionize—and positively charged sodium ions (Naϩ) and negatively charged chloride ions (Cl-) are found.

20 The Massage Connection: Anatomy and Physiology ELECTROLYTES molecular level in the body, these hydrogen bonds can alter the properties of proteins, making them Soluble inorganic molecules with ions that conduct an change their shape and structure. electrical current in solution are known as electrolytes. Matter exists as solids, liquids, or gases as a result HH HH of the degree of interaction between the atoms and molecules. For example, hydrogen molecules do not attract each other and, therefore, exist as gas. Water, however, has more interactions and exists as liquid throughout a wide temperature range. Hydrogen Hydrogen Chemical Reactions atoms molecule There is a constant reaction in the human body be- FIGURE 1.12. Representation of Covalent Bond Formation (e.g., tween atoms and molecules. Cells control these reac- hydrogen molecule) tions to stay alive. In the chemical reaction, new bonds form between atoms or present bonds break shell needs another electron to be complete. There- down to form a different compound. The term me- fore, one hydrogen atom shares its electron with an- tabolism refers to all the chemical reactions that oc- other hydrogen atom, completing their energy levels cur in the body. When a chemical reaction occurs, en- and forming a molecule. This is how hydrogen nor- ergy may be expended or released. mally exists—in pairs, and is referred to as hydrogen molecules. A hydrogen molecule is symbolized as H2. What is energy? Energy is the capacity to work, and work is movement or a change in the physical struc- Similarly, many different elements may bond to- ture of matter. Energy can be in two forms—potential gether. Carbon dioxide gas has one carbon atom and energy or kinetic energy. For example, imagine an two oxygen atoms bonded covalently (CO2). Water elastic band stretched across two poles. The stretched has two hydrogen atoms and one oxygen atom elastic band has potential energy. If the band comes bonded covalently (H2O). Elements may share one, two, or three electrons. In the human body, covalent δ- bonds are the most common. H O When covalent bonds are formed, the electrons may be shared equally or unequally between the specific O+ atoms. When shared equally, these bonds are known as nonpolar covalent bonds. Sometimes, one atom at- H HH tracts the shared electron more than the other atom. In this case, the atom that attracts the electron to a greater Oxygen Hydrogen δ+ δ+ degree would be slightly more negatively charged than atom atoms the other atom. The other atom will be slightly more Water positively charged. These charges are represented with molecule the symbol ␦ϩ or ␦- (see Figure 1.13). These covalent bonds are known as polar covalent bonds. FIGURE 1.13. Representation of Polar Covalent Bond Hydrogen Bonds Hydrogen δ- Water bonds δ+ δ+ molecules Other than ionic and covalent bonds, other weak at- tractions may be present between atoms of the same OH molecule or compound or between atoms in other molecules. The most important of these weak attrac- H tions are hydrogen bonds, in which a hydrogen atom involved in a polar covalent bond is attracted to oxy- FIGURE 1.14. Hydrogen Bonds Holding Water Molecules To- gen or nitrogen involved in a polar covalent bond by gether itself. This attraction is important. Although mole- cules are not formed through the hydrogen bonds, this bonding can alter the shape of the molecules. For example, it is this weak attraction that holds water together and makes it form a drop. We refer to this force as surface tension (see Figure 1.14). At the

Chapter 1—Introduction 21 undone from one pole, it springs back to its original Different Types of Mixtures length. This is kinetic energy. Of course, kinetic energy was initially used to stretch the elastic band and tie it When different elements or compounds are blended to- to the two poles. Remember that energy cannot be lost, gether without forming chemical bonds, a mixture is it is only converted from one form to another. formed. For example, if you mix salt and sugar together, you form a dry mixture. Now, if you add some water, During chemical reactions, much of the energy in you form a liquid mixture. In both, no chemical bonds the body is converted to heat, which maintains the are formed. core body temperature. When the body is cold, me- tabolism (chemical reactions) increases and more Three different mixtures can be formed in liquids— heat is produced. That’s why we shiver. The muscles solution, colloid, and suspension. In a solution, the ele- quickly contract and relax (shivering), and the chem- ments/compounds mixed with water are small and ical reactions that occur during this process generate evenly dispersed. Hence, a solution appears clear. The the needed heat. fluid in the solution is known as the solvent, and the dis- solved elements/compounds are known as solutes. The body “captures” energy in the form of high- energy compounds. These compounds require energy In a colloid, the elements/compounds are larger parti- to build up; however, when broken down, they release cles; they tend to scatter light and make the mixture less a lot of energy. This high-energy compound is adeno- clear or transparent. Although the particles are large, sine triphosphate (ATP). ATP is formed from the they do not settle down if the mixture is left undisturbed. chemicals adenosine monophosphate (AMP) and Milk is an example of a colloid. adenosine diphosphate (ADP) by combining with phosphorus. For example, chemical reactions in the In a suspension, the particles are very large and tend body break glucose down into smaller compounds. to settle down to the bottom of the container if left undis- The energy that is released is “captured” by combin- turbed for some time. An example of a suspension is a ing ADP with organic phosphate to form ATP. When mixture of sand particles of different sizes in water. If the mechanical energy is needed to walk, ATP is broken mixture is left undisturbed, the sand particles settle to the down to release energy and ADP and P. bottom, according to the mass. In the body, blood is an example of a suspension. If undisturbed, the larger parti- cles—the cells—settle to the bottom of the container. Types of Chemical Reactions in the Body Reversible reactions may be represented as: Many types of reactions take place in the body. Some AB ↔ A ϩ B reactions occur to break down compounds into smaller bits. This is a decomposition reaction. The Role of Enzymes AB → A ϩ B The various chemical reactions in the body would proceed too slowly to be of any use if they did not This is what happens when food is broken down have mechanisms in place to speed up the reaction. and digested. Similarly, when a person loses weight, The enzyme is one of the mechanisms that help that fat is broken down into smaller fragments. Within the process. Enzymes are proteins and, although they do cell, chemical reactions break down substances and not actually participate in the chemical reaction it- the energy released is used to do work. This process self, facilitate the reaction. Enzymes do not get con- is known as catabolism. sumed or altered in the process. The body has nu- merous enzymes that speed up specific chemical Building up, or synthesis, is the opposite of decom- reactions. The importance of specific enzymes is re- position. In this process, kinetic energy is invariably alized when one of them is deficient in the body. used to form compounds from fragments. The kinetic energy is converted to potential energy to be used later Enzyme activity can be modified by various factors, in a decomposition reaction when work is needed. The such as temperature, acidity, or alkalinity. For exam- process of building up is known as anabolism. ple, the activity of many enzymes is significantly re- duced when the temperature drops, slowing down A ϩ B → AB chemical reactions. Similarly, an acidic environment is detrimental to enzymes. When muscle activity is in- Another reaction that occurs in the body is ex- creased, many chemical reactions are triggered to change. In this process, the fragments get shuffled. produce energy for contraction. One of the metabo- lites formed, especially if oxygen supply is inadequate, AB ϩ CD → AD ϩ CB is lactic acid. If this metabolite is not rapidly removed, the muscle environment becomes acidic and the ac- Some reactions can proceed in both ways. The di- rection in which the reaction proceeds is altered by many factors, referred to as reversible reactions. AB → A ϩ B → AB

22 The Massage Connection: Anatomy and Physiology ACIDS AND BASES carbonate and carbonic acid compounds work as buffers. The body has both inorganic and organic acids and bases. An acid is any solute that dissociates in solution and re- HCO3- ϩ Hϩ → H2CO3 → H2O ϩ CO2 leases hydrogen ions, lowering the pH. A base is a solute that removes hydrogen ions from a solution and, thereby, In this chemical reaction, HCO3 (bicarbonate), a increases the pH. weak base, combines with the hydrogen ions to form H2CO3 (carbonic acid), a weak acid. This weak acid tivity of various enzymes slows down or stops and can be further broken down to CO2 (carbon dioxide), muscle fatigue results. which can be breathed out, and H2O (water), which can be used for other reactions or excreted by the kid- Acidity and Alkalinity neys. Alternately, if the pH becomes acidic, the weak carbonic acid H2CO3 can break down to form HCO3- For the purpose of enzyme activity and to maintain (a weak base) and Hϩ (hydrogen ions). the shape and structure of the proteins, the body must maintain the right state of acidity and alkalin- Important Organic Compounds in the Body ity. If there are more Hϩ (hydrogen ions), a solution is acidic. If there are more OH- (hydroxyl ions), the so- Organic compounds are compounds that have the el- lution is alkaline. The acidity and alkalinity of a solu- ements carbon, hydrogen and, usually, oxygen. Many tion is measured in terms of pH (hydrogen ion con- of the compounds have the carbon atoms in chains, centration). As the quantity of hydrogen ion is so linked by covalent bonds. There are four important small, it is cumbersome to express in actual numbers. organic compounds in the body—carbohydrates; If needed, the number would be something like proteins; fats or lipids; and nucleic acids. The first 0.0000001. To make it easier, this is expressed by pH. three are vital sources of energy in the body. The The pH is actually a measure of hydrogen ion con- structure of the body is mostly made up of proteins. centration in the body fluid; the pH scale extends Lipids are needed for building certain structures, from 0 to 14. Water is considered to be a pH of 7.0; a such as cell membranes. Lipids are also stored and neutral pH. This means that water contains used as a reserve. Nucleic acids are used to form ge- 0.0000001, or 1 Œ 10-7 of a mole of hydrogen ions per netic material. liter. If the pH is lower than 7.0, it denotes that the fluid has more hydrogen ions or that it is acidic. For Carbohydrates example, if a solution has a pH of 5.0, it contains 0.00001 or 1 Œ 10-5 of a mole of hydrogen ions per Carbohydrates are organic compounds that have car- liter (i.e., more hydrogen ions than a solution of pH bon, hydrogen, and oxygen in a ratio of 1:2:1. Sugars 7.0). If a solution has a pH above 7.0, it has less hy- and starches are typical examples. Carbohydrates are drogen ions than water and is alkaline. typical sources of energy for the cell and can be eas- The pH of the body is 7.4 (range, 7.35–7.45) (i.e., True Meaning of Organic slightly alkaline). For body enzymes to be active and for chemical reactions to proceed optimally, it is vital The term “organic” is often used to denote something that pH be maintained at this level. This implies that natural from nature, without it being contaminated by the body needs regulatory mechanisms that monitor synthetic, man-made substances. According to the scien- the hydrogen ion levels carefully and get rid of them tific definition, organic compounds are chemical struc- as and when they form above normal levels. tures that always have carbon and hydrogen as part of their basic structure. One of the body’s compensatory mechanisms is the presence of many buffers. Buffers are compounds Inorganic compounds are chemical structures that, in that prevent the hydrogen ion concentration from general, do not have carbon and hydrogen atoms as the fluctuating too much and too rapidly to alter the pH. primary structure. The body uses buffers to convert strong acids (that dissociate easily into hydrogen ions) to weak acids Body Weight and Organic Compounds (that dissociate less easily). Proteins, hemoglobin, and a combination of bicarbonate and carbonic acid Carbohydrates account for 2–3% of body weight; lipids, compounds are a few of the buffers present in body 10–12%; and proteins, about 20%. fluids. The later is an important buffer. The following chemical reaction indicates how a combination of bi-

Chapter 1—Introduction 23 ily broken down by the cells of the body. Carbohy- The enzymes that facilitate chemical reactions are drates may be simple or complex. proteins, as are the buffers. The blood contains pro- tein in the plasma. Hemoglobin is a plasma protein Simple sugars or monosaccharides contain 2–7 used to transport gases. The antibodies are plasma carbon atoms. Glucose, for example, has six carbon proteins used in defense. Many of the hormones are atoms. Fructose, found in fruits, is another example. made of proteins. Simple sugars dissolve easily in water and are easily transported in the blood. Complex sugars are formed Proteins consist of organic molecules chains known by the combination of two or more simple sugars. as amino acids. There are about 20 significant amino They are broken down by the digestive tract into its acids in the human body. Different proteins in the body simplest form before being absorbed into the body. are formed by combining amino acids, using covalent bonds in different sequences. A protein chain may have Simple sugars that are absorbed are reconverted any number of amino acids and is known as a polypep- by chemical reactions in the presence of enzymes tide. Some proteins may have 100,000 or more amino into various complex forms by the liver, muscle, and acids. Each amino acid has a different chemical struc- other tissues. Glycogen is one form of complex car- ture and this, in turn, alters its properties. bohydrate. This form of carbohydrate is insoluble in body fluids. When the demand for energy goes up, The shape of a protein is one property that may be glycogen is broken down into its simple form and altered. Certain proteins may be flat and appear as a transported by blood to the needed areas. long chain; certain proteins are more complex and form spirals. Others may be folded or coiled to form Lipids complex three-dimensional structures (e.g., hemoglo- bin). The structural properties are determined by the Lipids are organic compounds that have carbon, hy- sequence in which the amino acids are arranged. The drogen, and oxygen atoms, however, in a different ra- alteration of just one amino acid sequence can alter tio than carbohydrates. These compounds are insolu- the function of the protein drastically, as in the ex- ble in water and must be transported in the blood by ample of sickle cell anemia given earlier. special mechanisms. For example, in blood, lipids combine with proteins and are carried as lipopro- Nucleic Acids teins. Lipids are used to form important structures, such as cell membranes and certain hormones, and Nucleic acids are large organic molecules containing are an important source of energy. When there is carbon, hydrogen, oxygen, nitrogen, and phosphorus. more lipid supply than needed, it is stored in various Found in the nucleus of the cell, they are important regions for future use. The properties of lipids make for storing and processing information in every cell. them important body insulators. Fatty acids, glyc- Nucleic acid is the major component of ova and erides, steroids, and phospholipids are some of the sperm and conveys such information as shape, eye important lipids found in the body. color, and sex. There are two types of nucleic acid— DNA (deoxyribonucleic acid) and RNA (ribonu- Proteins cleic acid). Proteins are the organic compounds that are most DNA is in the form of a double helix (i.e., two spi- abundant in the body. All proteins contain carbon, rals, parallel to each other). The two strands are hydrogen, oxygen, and nitrogen. In addition, some proteins may contain sulfur. There are about 100,000 AMINO ACID different kinds of proteins in the body. The word amino is derived from the presence of amino Proteins form the structural framework for the group (nitrogen and two hydrogen atoms—NH2) and an body. The bulk of our muscles are made of proteins. acid group (carbon, two oxygen, and hydrogen—COOH). SATURATED AND UNSATURATED FAT GLYCOPROTEIN A small change in the chemical bond in fatty acids alters Some organic compounds exist as a combination of pro- their properties. There are two forms of fatty acids of im- teins and carbohydrates. An example is glycoprotein, a portance—saturated and unsaturated fatty acids. Although large protein with small carbohydrate groups attached. the body can break down both types, the presence of in- Antigens are examples of glycoproteins. creased amount of saturated fatty acids in the diet in- creases the risk of heart disease. Ice cream, fatty meat, and butter have a high content of saturated fatty acids.

24 The Massage Connection: Anatomy and Physiology held together by hydrogen bonds. A small segment nections between cell membranes of adjacent cells of DNA molecule forms a gene. Each gene deter- help stabilize the tissue. mines the traits we inherit from our parents. They also control protein synthesis in each cell. The RNA Cytoplasm conveys the message from the gene to the cell and determines the amino acids sequence when proteins The material enclosed by the cell membrane is are synthesized. known as cytoplasm (see Figure 1.15). The cyto- plasm contains the nucleus and special structures, or High-Energy Compounds organelles, floating in the fluid. The fluid inside the cell is known as the intracellular fluid, or cytosol. All cells require energy to carry out their functions. Ions, soluble and insoluble proteins, and waste prod- This energy is derived by catabolism of organic sub- ucts can be found in the cytosol. The major difference stances in the presence of enzymes. The energy liber- between the intracellular fluid and extracellular fluid ated is stored as potential energy in the form of high- is that the intracellular fluid has more potassium ions energy bonds. High-energy bonds are covalent and proteins. In addition, it has stored nutrients in bonds created in specific organic substrates in the the form of glycogen and amino acids. presence of enzymes. When the cell needs energy, these bonds are broken and the energy harnessed. Organelles AMP is the most important organic substrate used The cell has many organelles. Some of the organelles by the cells to form covalent bonds. The cells use the are enclosed in a lipid membrane, separating them energy liberated by nutrient breakdown to convert from the cytosol; others are in direct contact with the AMP to ADP, which is then converted to ATP. Both cytosol (Figure 1.15). The membranous organelles in- ADP and ATP are formed by attaching phosphate clude the mitochondria, endoplasmic reticulum, groups by covalent bonds. the Golgi apparatus, lysosomes, and peroxisomes. The nonmembranous structures include the cy- ADP ϩ phosphate group ϩ energy → ATP ϩ H2O toskeleton, the microvilli, centrioles, cilia, fla- ATP → ADP ϩ phosphate group ϩ energy gella, and ribosomes. As the body needs energy, ATP is broken down. Mitochondria Other compounds with high-energy bonds exist, but ATP is the most abundant. The mitochondria are double-membrane structures, which may be long and slender or short and fat. The CELLULAR LEVEL OF ORGANIZATION number of mitochondrion vary from cell to cell, from red blood cells, having no mitochondria, to liver cells, So far, we have viewed the body at the chemical level which are packed with them. The presence of mito- and reduced it to a collection of chemicals. Such chondria indicates the demand for energy by specific fragmentation is useful in understanding the physical cells. properties of the body and how the chemical struc- tures contribute to the property. However, the body is The inner membrane of the mitochondria is much more than a mixture of chemical compounds. thrown into folds to increase the surface area. The in- It is a dynamic, living being with its functional unit, side of the mitochondria contains the enzymes re- the cell, behaving like a miniature human, respond- quired for breaking down nutrients to liberate energy ing to internal and external stimuli. for cellular function; 95% of the ATP requirements are provided by mitochondrial activity. The human body has two classes of cells—somatic cells and sex cells. The somatic cells include all cells Endoplasmic Reticulum other than ova and sperm. The endoplasmic reticulum, as the term suggests, is a Typically, cells are surrounded by a medium network of intracellular membranes (which are in known as extracellular fluid. Of the extracellular the form of tubes and sacs) that is connected to the fluid, the fluid that actually surrounds the cells nuclear membrane. It contains enzymes and partici- (i.e., fluid not inside blood vessels) is known as the pates in protein and lipid synthesis. Some endoplas- interstitial fluid. The inside of the cell is separated mic reticulum appear smooth—smooth endoplasmic form the interstitial fluid by the cell membrane, reticulum—while others appear rough as a result of which plays many important roles—it serves as a the presence of ribosomes (discussed later). physical barrier between the inside of the cell and the extracellular fluid; it controls the entry of nu- The function of the endoplasmic reticulum varies trients and other substances; and it contains spe- from cell to cell. The rough endoplasmic reticulum cial receptors that respond to specific stimuli and alter the functioning of the inside of the cell. Con-

Chapter 1—Introduction 25 Chromatin Centrioles Mitochondrion Endoplasmic Pinocyctic vesicle reticulum Nucleolus Ribosomes Nucleus Cytoskeleton Golgi apparatus Cell membrane: Cytoplasm Protein Lipid Protein Lysosome Pinocyctic vesicle FIGURE 1.15. The Structure of a Typical Cell helps manufacture, process, and sort proteins. containing contents to be destroyed. On fusion, the Smooth endoplasmic reticulum helps manufacture enzymes become activated and digest the contents. fats and steroids. In muscle cells, it stores the cal- Substances that can be recycled diffuse back into the cium required for muscle contraction. In liver cells, it cytosol. Unwanted contents are expelled into the ex- contains enzymes that help detoxify harmful agents tracellular fluid by exocytosis. In sperm cells, lysoso- such as drugs and alcohol. mal enzymes are secreted outside and help the sperm penetrate the ovum. Golgi Apparatus (Golgi Complex) Peroxisomes The Golgi apparatus appears as flattened membrane disks known as saccules. If considered similar to a Peroxisomes are similar to lysosomes, except they factory, endoplasmic reticulum serves as the packag- help detoxify substances, such as alcohol and hydro- ing center of the cell. Chemicals manufactured by the gen peroxide, that are produced by the cell. In this endoplasmic reticulum enter the Golgi complex way, peroxisomes protect the cell from the harmful where they are processed, sorted, and packaged in effects of toxic substances. secretory vesicles ready for dispatch to the outside of the cell, or for storage inside the cell as storage vesi- Cytoskeleton cles. Secretions, such as hormones and enzymes, are packaged by this structure. The cytoskeleton is actually a framework of proteins located inside the cell that gives the cell its flexibility Lysosomes and strength. The cytoskeleton is in the form of fila- ments (threadlike structures) and tubules (micro- Lysosomes are vesicles filled with digestive enzymes. tubules). The filaments help anchor organelles inside The lysosomes are manufactured in the Golgi appa- the cell, as well as anchor the cells to surrounding ar- ratus. The lysosomes enzymes are activated when eas. Tubules help maintain the shape of the cell and they fuse with damaged organelles or other vesicles help transport substances within the cell.

26 The Massage Connection: Anatomy and Physiology Microvilli brane. Channels in the nuclear membrane control the movement of substances in and out of the nucleus. Microvilli are small fingerlike projections of the cell The nucleus contains a denser structure called the membrane that increase the surface area. They are nucleolus, in which ribosomes (containing RNA) are found in those cells involved in absorbing substances assembled. from the extracellular fluid. Unlike the processes oc- curred by the cell membrane in endocytosis, the mi- The nucleus contains all the information required crovilli are more stable and are anchored to the cy- for the cell to function and controls all cellular oper- toskeleton of the cell. The microvilli present on the ations. The nucleus has the information needed for surface of intestinal cells increase the surface area for the manufacture of more than 100,000 proteins. It absorption by 20%. also controls which proteins will be synthesized and in what amounts in a given time. The Centrosome The information required by the cell is stored in The centrosome is a structure located close to the nu- DNA strands. The DNA strands are found in thread- cleus. It consists of the pericentriolar area, which is like structures known as chromosomes. Each hu- composed of protein fibers and centrioles. The cen- man cell has 23 pairs of chromosomes. trioles are two, short, cylindrical structure composed of microtubules. They are only found in those cells DNA is actually a double-helix strand, with the two capable of dividing. Muscle cell, neurons, mature red strands held together by hydrogen bonds (see Figure blood cells, and cardiac muscle cells—all cells not ca- 1.16). The genetic code in the DNA is in the se- pable of multiplying—lack centrioles. The centriole is quence of nitrogenous bases. The nitrogenous bases important at the time of cell division to separate DNA adenine, thymine, cytosine, and guanine are ar- material. ranged in different ways to form the genetic code. Three of the bases, arranged in a specific way, code for a specific amino acid. In this way, the DNA has Cilia Strand 1 Strand 2 Cilia are projections from the cell membrane found C Cytosine in certain cells, such as those in the respiratory tract. G Guanine Cilia have nine pairs of microtubules, surrounding a A Adenine central pair They move rhythmically in one direction T Thymine and move mucus and other secretions over the cell surface. Flagella Flagella (singular, flagellum) can be considered longer cilia. Rather than moving the fluid over the cell surface like the cilia, flagella help move the cell in the surrounding fluid. A good example of a cell with flagellum is the sperm cell of the testis. Ribosomes Hydrogen bond Ribosomes are tiny organelles that manufacture pro- teins. They may be fixed to the endoplasmic reticu- Phosphate lum (rough endoplasmic reticulum) or float freely in group the cytosol. Deoxyribose sugar The Nucleus FIGURE 1.16. The Structure of DNA The nucleus of the cell is a denser area found in most cells (mature red blood cells do not contain a nu- cleus). Some cells, such as skeletal muscle cells, may have more than one nucleus. A membrane known as the nuclear membrane, or nuclear envelope, sur- rounds the nucleus, resembling the plasma mem-