Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Human Anatomy & Physiology SEVENTH EDITION Elaine N. Marieb Katja Hoehn PowerPoint ® Lecture Slides prepared by Vince Austin, Bluegrass Technical and Community College C H A P T E R 1 The Human Body: An Orientation P A R T A

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Overview of Anatomy and Physiology  Anatomy – study of the structure of body parts and their relationships to one another  Physiology – study of the function of the body’s parts  Principle of Complementarity  Function always reflects structure  What a structure can do depends on its specific form

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Categories of Anatomy  Gross or macroscopic – studies structures seen with the naked eye  Systemic – body studied by system (skeletal, muscular)  Regional – studied by body part (head, neck, arms)  Microscopic – studies structures seen only with microscope  Cytology – study of cells  Histology – study of tissues  Developmental – studies changes in the body over the course of a lifetime

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Topics of Physiology  Functions of specific organ systems are studied  Often focuses on cellular or molecular events

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Levels of Structural Organization  Chemical – atoms  molecules  macromolecules  organelles  Cellular – cells are smallest unit of life  Tissues – groups of cells with similar functions  Organ – made up of different types of tissues that work together to perform a specific function  Organ system – consists of different organs that work closely together  Organism – total of all structures working together

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Smooth muscle cell Molecules Atoms Smooth muscle tissue Epithelial tissue Heart Blood vessels Smooth muscle tissue Connective tissue Blood vessel (organ) Cardiovascular system Cellular level Cells are made up of molecules. Tissue level Tissues consist of similar types of cells. Organ level Organs are made up of different types of tissues. Organ system level Organ systems consist of different organs that work together closely. Organismal level The human organism is made up of many organ systems. Chemical level Atoms combine to form molecules. Levels of Structural Organization Figure 1.1

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings 1 Molecules Atoms Chemical level Atoms combine to form molecules. Levels of Structural Organization Figure 1.1

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings 1 2 Smooth muscle cell Molecules Atoms Cellular level Cells are made up of molecules. Chemical level Atoms combine to form molecules. Levels of Structural Organization Figure 1.1

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Smooth muscle cell Molecules Atoms Smooth muscle tissue Cellular level Cells are made up of molecules. Tissue level Tissues consist of similar types of cells. Chemical level Atoms combine to form molecules. Levels of Structural Organization Figure 1.1

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Smooth muscle cell Molecules Atoms Smooth muscle tissue Epithelial tissue Smooth muscle tissue Connective tissue Blood vessel (organ) Cellular level Cells are made up of molecules. Tissue level Tissues consist of similar types of cells. Organ level Organs are made up of different types of tissues. Chemical level Atoms combine to form molecules. Levels of Structural Organization Figure 1.1

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Smooth muscle cell Molecules Atoms Smooth muscle tissue Epithelial tissue Heart Blood vessels Smooth muscle tissue Connective tissue Blood vessel (organ) Cardiovascular system Cellular level Cells are made up of molecules. Tissue level Tissues consist of similar types of cells. Organ level Organs are made up of different types of tissues. Organ system level Organ systems consist of different organs that work together closely. Chemical level Atoms combine to form molecules. Levels of Structural Organization Figure 1.1

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Smooth muscle cell Molecules Atoms Smooth muscle tissue Epithelial tissue Heart Blood vessels Smooth muscle tissue Connective tissue Blood vessel (organ) Cardiovascular system Cellular level Cells are made up of molecules. Tissue level Tissues consist of similar types of cells. Organ level Organs are made up of different types of tissues. Organ system level Organ systems consist of different organs that work together closely. Organismal level The human organism is made up of many organ systems. Chemical level Atoms combine to form molecules. Levels of Structural Organization Figure 1.1

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Necessary Life Functions 1. Maintaining boundaries – the internal environment remains distinct from the external environment  Cellular level – accomplished by plasma membranes  Organismal level – accomplished by the skin 2. Movement – locomotion, propulsion (peristalsis), and contractility

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Necessary Life Functions 3. Responsiveness – ability to sense changes in the environment and respond to them 4. Digestion – breakdown of food for absorption 5. Metabolism – all chemical reactions that occur in the body 6. Excretion – removal of wastes from the body

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Necessary Life Functions 7. Reproduction – cellular and organismal levels  Cellular – an original cell divides and produces two identical daughter cells  Organismal – sperm and egg unite to make a whole new person 8. Growth – increase in size of a body part or of the organism

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Survival Needs 1. Nutrients – needed for energy and cell building 2. Oxygen – necessary for metabolic reactions 3. Water – provides the necessary environment for chemical reactions 4. Normal body temperature – necessary for chemical reactions to occur at life-sustaining rates (98.6  F or 37  C) 5. Atmospheric pressure – required for proper breathing and gas exchange in the lungs

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Homeostasis  Homeostasis – ability to maintain a relatively stable internal environment in an ever-changing outside world  The internal environment of the body is in a dynamic state of equilibrium  Chemical, thermal, and neural factors interact to maintain homeostasis

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Homeostatic Control Mechanisms  The three interdependent components of control mechanisms:  Receptor – monitors the environments and responds to changes (stimuli)  Control center – determines the set point at which the variable is maintained  Effector – provides the means to respond to stimuli

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Homeostatic Control Mechanisms Figure 1.4 Change detected by receptor Stimulus: Produces change in variable Input: Information sent along afferent pathway to Receptor (sensor)Effector Control center Variable (in homeostasis) Response of effector feeds back to influence magnitude of stimulus and returns variable to homeostasis Output: Information sent along efferent pathway to Imbalance

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Homeostatic Control Mechanisms Figure 1.4 Variable (in homeostasis)

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Homeostatic Control Mechanisms Figure 1.4 Stimulus: Produces change in variable Variable (in homeostasis) Imbalance 1

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Homeostatic Control Mechanisms Figure 1.4 Change detected by receptor Stimulus: Produces change in variable Receptor (sensor) Variable (in homeostasis) Imbalance 2 1

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Homeostatic Control Mechanisms Figure 1.4 Change detected by receptor Stimulus: Produces change in variable Input: Information sent along afferent pathway to Receptor (sensor) Control center Variable (in homeostasis) Imbalance 2 3 1

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Homeostatic Control Mechanisms Figure 1.4 Change detected by receptor Stimulus: Produces change in variable Input: Information sent along afferent pathway to Receptor (sensor)Effector Control center Variable (in homeostasis) Output: Information sent along efferent pathway to Imbalance

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Homeostatic Control Mechanisms Figure 1.4 Change detected by receptor Stimulus: Produces change in variable Input: Information sent along afferent pathway to Receptor (sensor)Effector Control center Variable (in homeostasis) Response of effector feeds back to influence magnitude of stimulus and returns variable to homeostasis Output: Information sent along efferent pathway to

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Negative Feedback  Negative feedback mechanism: the output shuts off the original stimulus  Causes the variable to change in a direction opposite to that of the initial change  Examples: Regulation of body temperature; Regulation of heart rate, blood pressure, blood levels of oxygen

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.5 Signal wire turns heater on Signal wire turns heater off Response; temperature rises Response; temperature drops Stimulus: rising room temperature Stimulus: dropping room temperature Balance Effector (heater) Effector (heater) Set point Control center (thermostat) Heater off Set point Receptor-sensor (thermometer in Thermostat) Control center (thermostat) Heater on Imbalance Receptor-sensor (thermometer in Thermostat)

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.5 Balance

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.5 Stimulus: rising room temperature Balance Imbalance

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.5 Stimulus: rising room temperature Balance Imbalance Receptor-sensor (thermometer In thermostat) Set point

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.5 Stimulus: rising room temperature Balance Imbalance Receptor-sensor (thermometer In thermostat) Set point Control center (thermostat)

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.5 Signal wire turns heater off Stimulus: rising room temperature Balance Effector (heater) Stimulus: dropping room temperature Imbalance Receptor-sensor (thermometer In thermostat) Set point Control center (thermostat) Heater off

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.5 Signal wire turns heater off Response; temperature drops Stimulus: rising room temperature Balance Effector (heater) Stimulus: dropping room temperature Receptor-sensor (thermometer In thermostat) Set point Control center (thermostat) Heater off

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.5 Stimulus: dropping room temperature Balance Imbalance

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.5 Stimulus: dropping room temperature Balance Set point Receptor-sensor (thermometer in Thermostat) Imbalance

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.5 Stimulus: dropping room temperature Balance Set point Receptor-sensor (thermometer in Thermostat) Control center (thermostat) Imbalance

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.5 Signal wire turns heater on Stimulus: dropping room temperature Balance Effector (heater) Set point Receptor-sensor (thermometer in Thermostat) Control center (thermostat) Heater on Imbalance

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.5 Signal wire turns heater on Response; temperature rises Stimulus: dropping room temperature Balance Effector (heater) Set point Receptor-sensor (thermometer in Thermostat) Control center (thermostat) Heater on

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.5 Signal wire turns heater on Signal wire turns heater off Response; temperature rises Response; temperature drops Stimulus: rising room temperature Stimulus: dropping room temperature Balance Effector (heater) Effector (heater) Set point Control center (thermostat) Heater off Set point Receptor-sensor (thermometer in Thermostat) Control center (thermostat) Heater on Imbalance Receptor-sensor (thermometer in Thermostat)

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Positive Feedback  Positive feedback mechanism: the output enhances or exaggerates the original stimulus  Causes the change to proceed in the same direction as the initial disturbance  Examples: Regulation of blood clotting; birth of a baby Figure 1.6

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.6 Released chemicals attract more platelets Clotting occurs as platelets adhere to site and release chemicals Break or tear in blood vessel wall Feedback cycle initiated Feedback cycle ends after clot seals break Clotting proceeds; newly forming clot grows

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.6 Break or tear in blood vessel wall Feedback cycle initiated 1

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.6 Clotting occurs as platelets adhere to site and release chemicals Break or tear in blood vessel wall Feedback cycle initiated 2 1

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.6 Released chemicals attract more platelets Clotting occurs as platelets adhere to site and release chemicals Break or tear in blood vessel wall Feedback cycle initiated 2 1 3

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.6 Released chemicals attract more platelets Clotting occurs as platelets adhere to site and release chemicals Break or tear in blood vessel wall Feedback cycle initiated Clotting proceeds; newly forming clot grows

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.6 Released chemicals attract more platelets Clotting occurs as platelets adhere to site and release chemicals Break or tear in blood vessel wall Feedback cycle initiated Feedback cycle ends after clot seals break Clotting proceeds; newly forming clot grows

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Homeostatic Imbalance  Disturbance of homeostasis or the body’s normal equilibrium  Overwhelms the usual negative feedback mechanisms allows destructive positive feedback mechanisms to take over  Often results in disease  Pathology: study of disease conditions that occur