An Overview of Anatomy and Physiology (해부학 기초정리)

An Overview of Anatomy and Physiology (pp. 2-3) 1. Anatomy is the study of body structures and their relationships. Physiology is the science of how body parts function. Topics of Anatomy (pp. 2-3) 2. Major subdivisions of anatomy include gross anatomy, microscopic anatomy, and developmental anatomy. Topics of Physiology (p. 3) 3. Typically, physiology concerns the functioning of specific organs or organ systems. Examples include cardiac physiology, renal physiology, and muscle physiology. 4. Physiology is explained by chemical and physical principles. Complementarity of Structure and Function (p. 3) 5. Anatomy and physiology are inseparable: What a body can do depends on the unique architecture of its parts. This is called the complementarity of structure and function. Levels of Structural Organization (pp. 3-4) 1. The levels of structural organization of the body, from simplest to most complex, are: chemical, cellular, tissue, organ, organ system, and organismal. 2. The 11 organ systems of the body are the integumentary, skeletal, muscular, nervous, endocrine, cardiovascular, lymphatic, respiratory, digestive, urinary, and reproductive systems. The immune system is a functional system closely associated with the lymphatic system. (For functions of these systems see pp. 6–7). Maintaining Life (pp. 4-9) Necessary Life Functions (pp. 4-8) 1. All living organisms carry out certain vital functional activities necessary for life, including maintenance of boundaries, movement, responsiveness, digestion, metabolism, excretion, reproduction, and growth. Survival Needs (pp. 8-9) 2. Survival needs include nutrients, water, oxygen, and appropriate body temperature and atmospheric pressure. Homeostasis (pp. 9-12) 1. Homeostasis is a dynamic equilibrium of the internal environment. All body systems contribute to homeostasis, but the nervous and endocrine systems are most important. Homeostasis is necessary for health. Homeostatic Control Mechanisms (pp. 9-12) 2. Control systems of the body contain at least three elements: receptor(s), control center, and effector(s). 3. Negative feedback mechanisms reduce the original stimulus, and are essential for maintaining homeostasis. Body temperature, heart rate, breathing rate and depth, and blood levels of glucose and certain ions are regulated by negative feedback mechanisms. 4. Positive feedback mechanisms intensify the initial stimulus, leading to an enhancement of the response. Positive feedback mechanisms rarely contribute to homeostasis, but blood clotting and labor contractions are regulated by such mechanisms. Homeostatic Imbalance (p. 11-12) 5. With age, the efficiency of negative feedback mechanisms declines, and positive feedback mechanisms occur more frequently. These changes underlie certain disease conditions. The Language of Anatomy (pp. 12-20) Anatomical Position and Directional Terms (pp. 12-14) 1. In the anatomical position, the body is erect, facing forward, feet together, arms at sides with palms forward. 2. Directional terms allow body parts to be located precisely. Terms used to describe body directions and orientation include: superior/inferior; anterior/posterior; ventral/dorsal; medial/lateral; intermediate; proximal/distal; and superficial/deep. Regional Terms (pp. 14) 3. Regional terms are used to designate specific areas of the body (see Figure 1.7). Anatomical Variability (p. 15) 4. People vary internally as well as externally, although extreme variations are rare. Body Planes and Sections (p. 15) 5. The body or its organs may be cut along planes, or imaginary lines, to produce different types of sections. Frequently used planes are sagittal, frontal, and transverse. Body Cavities and Membranes (pp. 15-19) 6. The body contains two major closed cavities. The dorsal cavity, subdivided into the cranial and spinal cavities, contains the brain and spinal cord. The ventral cavity is subdivided into the superior thoracic cavity, which houses the heart and lungs, and the inferior abdominopelvic cavity, which contains the liver, digestive organs, and reproductive structures. 7. The walls of the ventral cavity and the surfaces of the organs it contains are covered with thin membranes, the parietal and visceral serosae, respectively. The serosae produce a thin fluid that decreases friction during organ functioning. 8. The abdominopelvic cavity may be divided by four planes into nine abdominal regions (epigastric, umbilical, hypogastric, right and left iliac, right and left lumbar, and right and left hypochondriac), or by two planes into four quadrants. (For boundaries and organs contained see Figures 1.11 and 1.12.) 9. There are several smaller body cavities. Most of these are in the head and open to the exterior.