Chapter 01 Major Themes of Anatomy and Physiology PDF

Because learning changes everything. ® Chapter 01 Major Themes of Anatomy and Physiology ANATOMY & PHYSIOLOGY The Unity of Form and Function TENTH EDITION KENNETH S. SALADIN © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written...

Because learning changes everything. ® Chapter 01 Major Themes of Anatomy and Physiology ANATOMY & PHYSIOLOGY The Unity of Form and Function TENTH EDITION KENNETH S. SALADIN © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC.  1.1 The Scope of Anatomy and Physiology Expected Learning Outcomes: Define anatomy and physiology and relate them to each other. Describe several ways of studying human anatomy © McGraw Hill, LLC 2  1.1 Introduction Anatomy—study of structure Physiology—study of function Anatomy and physiology are complementary and never entirely separable Physiology provides meaning to anatomy Anatomy is what makes physiology possible © McGraw Hill, LLC 3  1.1a Anatomy—The Study of Form 1 Ways to examine structure of the human body: Inspection—look at appearance Palpation—feeling a structure with the hands Auscultation—listening to sounds produced by body Percussion—tap on the body, feel for resistance, and listen to emitted sound for abnormalities Dissection—cutting and separating human body tissues to reveal tissue relationships; use a cadaver, a dead human body Comparative anatomy—study (for example, dissection) of multiple species to learn about form, function, and evolution Exploratory surgery—opening the living body to see what is wrong; now replaced by medical imaging to view inside without surgery Radiology—branch of medicine specializing in imaging © McGraw Hill, LLC 4  Anatomy—The Study of Form 2 Examining structure of the human body - Inspection: visual, Palpation: feeling with fingers, Auscultation: listening, Percussion: tapping on body. Medical imaging: Viewing the inside of the body without surgery Gross anatomy—study of structures that can be seen with the naked eye Histology (microscopic anatomy)—examination of tissues with microscope Histopathology—microscopic examination of tissues for signs of disease Cytology—study of structure and function of cells; fine detail (ultrastructure) may be resolved using an electron microscope © McGraw Hill, LLC 5  1.1b Physiology—The Study of Function Physiology uses the methods of experimental science to determine the functions of the structures. Subdisciplines of physiology include: Neurophysiology—physiology of nervous system Endocrinology—physiology of hormones Pathophysiology—mechanisms of disease Comparative physiology Study of different species to learn about body functions Basis for much of our understanding of human physiology and the development of new drugs and medical procedures © McGraw Hill, LLC 6  1.5 Human Structure Expected Learning Outcomes: List the levels of human structure from the most complex to the simplest. Discuss the clinical significance of anatomical variation among humans. © McGraw Hill, LLC 7  The Body’s Structural Hierarchy Organism composed of organ systems Organ systems composed of organs Organs composed of tissues Tissues composed of cells Cells composed of organelles Organelles composed of molecules Molecules composed of atoms Access the text alternative for slide images. Figure 1.5 © McGraw Hill, LLC 8  The Hierarchy of Complexity 1 Hierarchy of human complexity Organism: a single, complete individual Organ system: a group of organs with a unique collective functions. 11 organ systems in total. Organ: a structure composed of two or more tissue types that work together to carry out a particular function. Tissue: a group of similar cells and their intercellular materials in a discrete region of an organ performing a specific function Cells: the simplest body structure considered alive Organelles: microscopic structures in a cell that carry out its individual functions. © McGraw Hill, LLC 9  1.6 Human Function Expected Learning Outcomes: State the characteristics that distinguish living organisms from nonliving objects. Explain the importance of physiological variation among persons. Define homeostasis and explain why this concept is central to physiology. © McGraw Hill, LLC 10  1.6 Human Function 2 Expected Learning Outcomes (continued): Define negative feedback, give an example of it, and explain its importance to homeostasis. Define positive feedback and give examples of its beneficial and harmful effects. Define gradient and describe some examples. © McGraw Hill, LLC 11  1.6a Characteristics of Life 1 Life is a collection of properties that distinguish living from nonliving things Characteristics of life: Organization—living things exhibit a higher level of organization than nonliving things Cellular composition—living matter is always compartmentalized into one or more cells Metabolism—the sum of internal chemical change Responsiveness (excitability)—ability to sense and react to changes in environment (stimuli) Movement—movement of entire organism or of substances within the organism © McGraw Hill, LLC 12  Characteristics of Life 2 Characteristics of life (continued) Homeostasis—maintaining relatively stable internal conditions Development—change in form or function over time Differentiation—transformation of unspecialized cells into cells with a committed task Growth—increase in size; occurs through chemical change Reproduction—organisms produce copies of themselves; pass genes to offspring Evolution—genetic change from generation to generation; occurs due to mutations (change in DNA structure) Observe evolution in population as a whole; a single organism does not evolve over the course of its life © McGraw Hill, LLC 13  1.6b Physiological Variation Physiology is even more variable than anatomy Variations in sex, age, diet, weight, physical activity, genetics and environment Typical physiological values Reference man: 22 years old, 154 lb, light physical activity, consumes 2,800 kcal/day Reference woman: same as man except 128 lb and 2,000 kcal/day Just a Guideline Failure to consider variation can lead to overmedication of elderly or medicating women on the basis of research done on men © McGraw Hill, LLC 14  1.6c Negative Feedback and Homeostasis 1 Homeostasis—the ability to detect change, activate mechanisms that oppose it, and thereby maintain relatively stable internal conditions Negative feedback allows for dynamic equilibrium within a limited range around a set point The body senses a change and “negates” or reverses it The majority of homeostasis is controlled by negative feedback. Loss of homeostatic control causes illness or death © McGraw Hill, LLC 15  Negative Feedback and Homeostasis 2 Homeostasis (continued) Internal conditions fluctuate within a limited range Dynamic equilibrium around a set point Negative feedback—mechanism that keeps a variable close to set point; the body senses a change and reverses it Because feedback mechanisms alter the original changes that triggered them, they are called feedback loops Example: homeostasis in body temperature If too warm, skin blood vessels dilate (vasodilation) and sweating begins (heat-losing mechanism) If too cold, skin blood vessels constrict (vasoconstriction) and shivering begins (heat-gaining mechanism) © McGraw Hill, LLC 16  Negative Feedback in Thermoregulation 1 Access the text alternative for slide images. Figure 1.7a © McGraw Hill, LLC 17  Negative Feedback in Thermoregulation 2 Access the text alternative for slide images. Figure 1.7b © McGraw Hill, LLC 18  Homeostatic Compensation for a Postural Change in Blood Pressure Access the text alternative for slide images. Figure 1.8 © McGraw Hill, LLC 19  Negative Feedback and Homeostasis 3 Homeostasis (continued) Example: homeostasis of blood pressure (baroreflex) Rise from bed, blood drains from head and blood pressure falls in this region Detected by baroreceptors that transmit signals to cardiac center of brainstem Cardiac center transmits signals to heart to increase heart rate, raising blood pressure and restoring homeostasis © McGraw Hill, LLC 20  Negative Feedback and Homeostasis 4 Homeostasis (continued) Baroreflex illustrates the common components of a feedback loop: Receptor—structure that senses change in the body (for example, the baroreceptors above heart that monitor blood pressure) Integrating (control) center—control center that processes the sensory information, “makes a decision,” and directs the response (for example, cardiac center of the brainstem) Effector—cell or organ that carries out the final corrective action to restore homeostasis (for example, the heart) © McGraw Hill, LLC 21  1.6d Positive Feedback and Rapid Change Positive feedback is a self-amplifying cycle Leads to greater change in the same direction, as opposed to the corrective action of negative feedback Normal way of producing rapid changes Examples: childbirth, blood clotting, protein digestion, and generation of nerve signals Can sometimes be dangerous, and therefore few feedback loops are positive feedback Example: vicious circle of runaway fever © McGraw Hill, LLC 22  Positive Feedback in Childbirth Access the text alternative for slide images. Figure 1.9 © McGraw Hill, LLC 23  Flow Down Gradients 1 Access the text alternative for slide images. Figure 1.10a © McGraw Hill, LLC 24  Flow Down Gradients 2 Access the text alternative for slide images. Figure 1.10b,c © McGraw Hill, LLC 25  Flow Down Gradients 3 Access the text alternative for slide images. Figure 1.10d,e © McGraw Hill, LLC 26  1.8 Review of Major Themes Key unifying principles of anatomy and physiology: Unity of form and function—anatomy and physiology complement each other and cannot be divorced from one another Cell theory—all structure and function result from the activity of cells Evolution—the human body is a product of evolution Hierarchy of complexity—human structure can be viewed as a series of levels of complexity Homeostasis—the purpose of most normal physiology is to maintain stable conditions within the body Gradients and flow—matter and energy tend to flow down gradients © McGraw Hill, LLC 27  Medical Imaging 1 Radiography (X-rays) Over half of all medical imaging Penetrate tissues to darken photographic film beneath the body; dense tissue appears white Radiopaque substances can be injected or swallowed to fill hollow structures, for example, blood vessels, intestinal tract Digital subtraction angiography (D S A) is useful for showing blockages and blood flow © McGraw Hill, LLC 28  Radiologic Images of the Head – X-Ray (Radiograph) © U.H.B. Trust/The Image Bank/Getty Images Access the text alternative for slide images. Figure 1.11a © McGraw Hill, LLC 29  Radiologic Images of the Head – Digital Subtraction Angiogram (DSA) © pang_oasis/Shutterstock Access the text alternative for slide images. Figure 1.11b © McGraw Hill, LLC 30  Medical Imaging 2 Computed tomography (CT scan) Formerly called a C A T scan Low-intensity X-rays and computer analysis Slice-type image Increased sharpness of image Magnetic resonance imaging (M R I) Superior quality to CT scan and no X-ray exposure Best for soft tissue Functional M R I (f M R I) shows real time changes in the brain © McGraw Hill, LLC 31  Radiologic Images of the Head – Computed Tomographic (CT) Scan © Miriam Maslo/Science Source Access the text alternative for slide images. Figure 1.11c © McGraw Hill, LLC 32  Radiologic Images of the Head – Magnetic Resonance Image (M R I) © UHB Trust/Getty Images Access the text alternative for slide images. Figure 1.11d © McGraw Hill, LLC 33  Medical Imaging 3 Positron emission tomography (P E T) Assesses metabolic state of tissue Inject radioactively labeled glucose Image color shows tissues using the most glucose at that moment Damaged tissues appear dark © McGraw Hill, LLC 34  Radiologic Images of the Head – Positron Emission Tomographic (PET) Scan © ISM/Sovereign/Medical Images Access the text alternative for slide images. Figure 1.11e © McGraw Hill, LLC 35  End of Main Content Because learning changes everything. ® www.mheducation.com © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC.