Homeostasis: The Foundation of Physiology Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Outline Physiology Levels of organization Basic Cell function Tissues/ organs/systems Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Outline Homeostasis Disruptions of homeostasis Fluid compartments Variables controlled contributions of systems Control systems intrinsic/extrinsic Feedfoward/ feedback Positive/negative Disruptions of homeostasis Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Physiology Study of body functions Two processes explain body functions Teleological Explanations are in terms of meeting a bodily need Mechanistic Explanations are in terms of cause and effect sequences Body is viewed as a machine Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Anatomy Study of the structure of the body Physiological mechanisms are possible through structural design Structure-Function relationships of the body include Heart receiving and pumping blood Teeth tearing and grinding food Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Functional Organization of the Body Levels of organization Chemical Molecules composed of atoms Cellular Cells are basic unit of life Tissue Organ Body system Organism Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Fig. 1.1, p. 3 5 6 4 3 1 2 2 3 4 5 1 6 Chemical level Cellular level Tissue level 4 Organ level 5 Body system level 6 Organism level Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Stepped art Fig. 1.1, p. 3

Basic Cell Functions Obtain nutrients and oxygen from surrounding environment Perform chemical reactions that provide energy for the cell Eliminate carbon dioxide and other wastes to surrounding environment Synthesize needed cellular components Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Basic Cell Functions Control exchange of materials between cell and its surrounding environment Sensing and responding to changes in surrounding environment Reproduction Exception Nerve cells and muscle cells lose their ability to reproduce during their early development Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Tissues Groups of cells with similar structure and specialized function Four primary types of tissues Muscle tissue Nervous tissue Epithelial tissue Connective tissue Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Tissues Muscle tissue Specialized for contracting and generating force Three types of muscle tissue Skeletal muscle Moves the skeleton Cardiac muscle Pumps blood out of the heart Smooth muscle Encloses and controls movement of contents through hollow tubes and organs Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Tissues Nervous tissue Epithelial tissue Consists of cells specialized for initiating and transmitting electrical impulses Found in brain, spinal cord, and nerves Epithelial tissue Consists of cells specialized for exchanging materials between the cell and its environment Organized into two general types of structures Epithelial sheets Secretory glands Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Tissues Connective tissue Connects, supports, and anchors various body parts Distinguished by having relatively few cells dispersed within an abundance of extracellular material Examples Tendons Bone Blood Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

The following photos are from Visuals Unlimited The following photos are from Visuals Unlimited. An instructor using a Thomson Learning textbook has the right to use these photos for the duration of the adoption in the classroom or on instructor’s course website so long as the credit specified here is visible on or under the photo at all times, and images are displayed at no larger than 1/4 screen at 72 dpi (web-ready JPGs available in folder “Bonus_Photos_JPGs” in “Media” folder). Instructors do not become the owners of these photos and do not have the right to grant permission to third parties to use this material. See the ReadMe for details. Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Credit: © Dr. Fred Hossler/Visuals Unlimited 98769 Credit: © Dr. Fred Hossler/Visuals Unlimited Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Hyaline cartilage. X64.

Credit: © Dr. David Phillips/Visuals Unlimited 98964 Credit: © Dr. David Phillips/Visuals Unlimited Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Collagen or dense connective tissue. X155.

Credit: © Dr. Richard Kessel/Visuals Unlimited 98990 Credit: © Dr. Richard Kessel/Visuals Unlimited Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Reticular fibers, silver preparation. X100.

Credit: © G.W. Willis, MD/Visuals Unlimited 164732 Credit: © G.W. Willis, MD/Visuals Unlimited Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Human unilocular (white) fat and adipose (adult fat). H&E stain. LM X100.

Credit: © G.W. Willis, MD/Visuals Unlimited 164740 Credit: © G.W. Willis, MD/Visuals Unlimited Human pseudostratified columnar epithelium lining the bronchus of the lung. H&E stain. X180. Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Credit: © G.W. Willis, MD/Visuals Unlimited 301193 Credit: © G.W. Willis, MD/Visuals Unlimited Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Stratified squamous epithelium from mouth mucosa. H&E stain. LM X100.

Credit: © Carolina Biological/Visuals Unlimited 310845 Credit: © Carolina Biological/Visuals Unlimited Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Simple columnar epithelium. LM X140.

Credit: © Carolina Biological/Visuals Unlimited 310887 Credit: © Carolina Biological/Visuals Unlimited Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Simple Squamous Epithelium. LM X75.

Credit: © Carolina Biological/Visuals Unlimited 317178 Credit: © Carolina Biological/Visuals Unlimited Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Areolar (loose) connective tissue. LM X60.

Credit: © Carolina Biological/Visuals Unlimited 319245 Credit: © Carolina Biological/Visuals Unlimited Bone section showing osteocytes in lacunae arranged in concentric circles surrounding Haversian canals. LM X75. Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Credit: © David Phillips/Visuals Unlimited 308775 Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Microscopic technique series - Cheek cells. Nomarski view. LM X75.

Credit: © David Phillips/Visuals Unlimited 308777 Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Microscopic technique series - Cheek cells. Phase view. LM X75.

Credit: © David Phillips/Visuals Unlimited 308778 Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Microscopic technique series -Cheek cells. Darkfield view. LM X75.

Credit: © Dr. Richard Kessel & Dr. Randy Kardon/Tissues & Organs/ 228388 Credit: © Dr. Richard Kessel & Dr. Randy Kardon/Tissues & Organs/ Visuals Unlimited A long bone showing the compact bone (yellow) surrounding the spongy or cancellous bone (orange). Compact bone consist of a dense matrix resembling a solid mass. The spongy region consists of a network of bony spicules called trabeculae. SEM X40. Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

306457 Credit: © UMW Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Colony of undifferentiated human embryonic stem cells. LM X5.14

Credit: © Dr. Wolf Fahrenbach/Visuals Unlimited 196178 Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Surface of a human fingertip with sweat droplets. SEM X120.

Credit: © Carolina Biological/Visuals Unlimited 318237 Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Sweat gland duct in the skin. LM X5.

301276 Credit: © Geron Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Cardiomyocyte differentiated from human embryonic stem cells.

Organs Consist of two or more types of primary tissues that function together to perform a particular function or functions Example Stomach Inside of stomach lined with epithelial tissue Wall of stomach contains smooth muscle Nervous tissue in stomach controls muscle contraction and gland secretion Connective tissue binds all the above tissues together Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Body Systems Groups of organs that perform related functions and interact to accomplish a common activity essential to survival of the whole body Do not act in isolation from one another Human body has 11 systems Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Body Systems Circulatory System Digestive System Respiratory System Urinary System Skeletal System Muscular System Integumentary System Immune System Nervous System Endocrine System Reproductive System Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Body Systems Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Body Systems Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Homeostasis Defined as maintenance of a relatively stable internal environment Does not mean that composition, temperature, and other characteristics are absolutely unchanging Homeostasis is essential for survival and function of all cells Each cell contributes to maintenance of a relatively stable internal environment Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Homeostasis Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Homeostasis Body cells are in contained in watery internal environment through which life-sustaining exchanges are made Extracellular fluid (ECF) Fluid environment in which the cells live (fluid outside the cells) Two components Plasma, interstitial fluid Intracellular fluid (ICF) Fluid contained within all body cells Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Homeostasis Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Homeostasis Factors homeostatically regulated include Concentration of nutrient molecules Concentration of O2 and CO2 Concentration of waste products pH Concentration of water, salt, and other electrolytes Volume and pressure Temperature Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Contributions of Body Systems to Homeostasis Circulatory system Carries materials from one part of the body to another Digestive system Breaks down dietary food into smaller molecules that can be distributed to body cells Transfers water and electrolytes from external environment to internal environment Eliminates undigested food residues to external environment in the feces Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Contributions of Body Systems to Homeostasis Respiratory system Gets O2 from and eliminates CO2 to the external environment Important in maintenance of proper pH of internal environment Urinary system Removes excess water, salt, acid, and other electrolytes from plasma and eliminates them in urine Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Contributions of Body Systems to Homeostasis Skeletal system Provides support and protection for soft tissues and organs Serves as storage reservoir for calcium Along with muscular system enables movement of body and its parts Bone marrow is ultimate source of all blood cells Muscular system Moves the bones Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Contributions of Body Systems to Homeostasis Integumentary system Serves as outer protective barrier Important in regulating body temperature Immune system Defends against foreign invaders and against body cells that have become cancerous Paves way for repairing or replacing injured or worn-out cells Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Contributions of Body Systems to Homeostasis Nervous system Controls and coordinates bodily activities that require rapid responses Detects and initiates reactions to changes in external environment Endocrine system Secreting glands of endocrine regulate activities that require duration rather than speed Controls concentration of nutrients and, by adjusting kidney function, controls internal environment’s volume and electrolyte composition Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Fig. 1.2a, p. 5 Surface epithelium Pocket epithelium cells Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Fig. 1.2a, p. 5

Fig. 1.2b, p. 5 Surface epithelium Duct cells Secretory exocrine gland cell Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Fig. 1.2b, p. 5

Fig. 1.2c, p. 5 Surface epithelium Connecting cells lost during development Secretory exocrine gland cell Blood vessels Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Fig. 1.2c, p. 5

Contributions of Body Systems to Homeostasis Reproductive system Not essential for homeostasis (not essential for survival of individual) Is essential for perpetuating the species Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Role of Body Systems in Homeostasis Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Homeostatic Control Systems In order to maintain homeostasis, control system must be able to Detect deviations from normal in the internal environment that need to be held within narrow limits Integrate this information with other relevant information Make appropriate adjustments in order to restore factor to its desired value Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Homeostatic Control Systems Control systems are grouped into two classes Intrinsic controls Local controls that are inherent in an organ Extrinsic controls Regulatory mechanisms initiated outside an organ Accomplished by nervous and endocrine systems Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Homeostatic Control Systems Feedforward Term used for responses made in anticipation of a change Feedback Refers to responses made after change has been detected Types of feedback systems Negative Positive Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Homeostatic Control Systems Negative feedback system Primary type of homeostatic control Opposes initial change Components Sensor Monitors magnitude of a controlled variable Control center Compares sensor’s input with a set point Effector Makes a response to produce a desired effect Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Homeostatic Control Systems Positive feedback system Amplifies an initial change Do not occur as often as negative feedback system Example Uterine contractions become increasingly stronger until the birth of the baby Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

Disruptions in Homeostasis Can lead to illness and death Pathophysiology Abnormal functioning of the body associated with disease Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning

During the minute that it will take you to read this page Your eyes will convert the information on this page into electrical signals that will transmit to your brain. Your brain will send chemical messengers through your nerves to control your body. Your heart will beat 70 times, pumping 5 liters of blood to your lungs and another 5 liters to the rest of your body. You will breathe in and out about 12 times. Your cells will consume 250 ml of oxygen and produce 200 ml of carbon dioxide. Your kidneys will produce 1 ml of urine. Your digestive system will be processing your last meal for transfer into your bloodstream. You will use about 2 calories of energy. Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Chapter Opener, p. 1

Fig. 1.6, p. 12 BODY SYSTEMS Body systems maintain homeostasis NERVOUS ENDOCRINE SYSTEM Information from the external environment relayed through the nervous system Regulate O2 RESPIRATORY SYSTEM Keeps internal fluids in INTEGUMENTARY SYSTEM HOMEOSTASIS CO2 Keeps foreign materials out Urine containing wastes and excess water and electrolytes URINARY SYSTEM Protects against foreign invaders IMMUNE SYSTEM Homeostasis essential for cell survival Nutrients, water, electrolytes DIGESTIVE SYSTEM Feces containing undigested food residue MUSCULAR AND SKELETAL SYSTEM Enables the body to interact with the external environment REPRODUCTIVE SYSTEM Sperm leave male CELLS Sperm enter female Exchanges with all other systems Exchanges with all other systems EXTERNAL ENVIRONMENT CIRCULATORY SYSTEM Cells make up body system Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Fig. 1.6, p. 12

Fig. 1-7a, p. 15 Figure 1.7: Negative feedback. (a) Components of a negative-feedback control system. Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Fig. 1-7a, p. 15

Fig. 1-7b, p. 15 Figure 1.7: Negative feedback. (b) Negative-feedback control of room temperature. Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Fig. 1-7b, p. 15

Fig. 1-7c, p. 15 Figure 1.7: Negative feedback. (c) Negative-feedback control of body temperature. Chapter 1 Homeostasis: The Foundation of Physiology Human Physiology by Lauralee Sherwood ©2007 Brooks/Cole-Thomson Learning Fig. 1-7c, p. 15