Human physiology

Cover
Title Page
Copyright Page
About the Author
Preface
Acknowledgments
Brief Contents
Contents
1 An Introduction to Physiology
	1.1 Physiology Defined
	1.2 Levels of Organization in the Body
	1.3 Life Processes
	1.4 Homeostasis
		Maintenance of Body Fluid Volume and Composition is Essential to Homeostasis
		Homeostasis Is Regulated via Feedback Systems and Feedforward Control
		Homeostatic Imbalances Can Lead to Disorders, Diseases, or Even Death
	1.5 Physiology as a Science
		The History of Physiology Spans Thousands of Years
		The Scientific Method Is a Systematic Way of Acquiring Knowledge About the Natural World
		Scientific Literature Helps Physiologists Conduct Research
		Physiologists Use the Mechanistic Approach to Explain How the Body Functions
		Concept Mapping Allows Physiologists to Illustrate the Relationships Between Ideas
	1.6 Key Themes of Physiology
	Critical Thinking
	From Research to Reality
2 Chemical Composition of the Body
	2.1 How Matter Is Organized
		All Forms of Matter Are Composed of Atoms
		An Atom Contains Protons, Neutrons, and Electrons
		Each Atom Has an Atomic Number and a Mass Number
		Atomic Mass Is Measured In Daltons
		Atoms Can Give Rise to Ions, Molecules, and Compounds
	2.2 Chemical Bonds
		Ionic Bonds Involve the Loss or Gain of Electrons
		Covalent Bonds Involve Sharing of Electrons
		Hydrogen Bonds Result from Attraction of Oppositely Charged Regions of Molecules
		Van der Waals Interactions Involve Transient Fluctuations in Electron Distribution
	2.3 Chemical Reactions
	2.4 Inorganic Compounds and Solutions
		Water Is Vital to Life
		Solutions, Colloids, and Suspensions Are Types of Mixtures
		Inorganic Acids, Bases, and Salts Dissociate When Dissolved in Water
		The Body’s Chemical Reactions Are Sensitive to Changes in pH
		Buffer Systems Convert Strong Acids or Bases into Weak Acids or Bases
	2.5 Organic Compounds
		Carbon and Its Functional Groups Provide Useful Properties to Living Organisms
		Carbohydrates Are Important Sources of Chemical Energy
		Lipids Contribute to Energy Storage, Membrane Structure, and Hormone Production
		Proteins Are Chains of Amino Acids That Have Diverse Roles
		Nucleic Acids Store and Express Genetic Information
		ATP Serves as the Energy Currency of Living Systems
	Critical Thinking
	From Research to Reality
3 Cells
	3.1 Components of a Cell
	3.2 The Plasma Membrane
		The Plasma Membrane Consists of a Lipid Bilayer and a Variety of Proteins
		Membrane Proteins Have Many Functions
		Membrane Fluidity Allows Membrane Components to Interact and Move Around
	3.3 Cytoplasm
		The Cytosol Is the Site of Many Chemical Reactions
		Organelles Function in Cellular Growth, Maintenance, and Reproduction
	3.4 Nucleus
	3.5 Gene Expression
		Transcription Conveys Genetic Information from DNA to RNA
		Translation Uses Genetic Information Carried by mRNA to Synthesize a Protein
	3.6 Cell Division
		Somatic Cell Division Produces Two Identical Cells
		Cell Destiny Is Controlled by Many Factors
	3.7 Cellular Diversity
	3.8 Organization of Cells into Tissues
		Epithelial Tissue Serves as a Barrier, Secretes Substances, and Absorbs Materials
		Connective Tissue Supports, Insulates, and Protects the Organs of the Body
		Muscle Tissue Specializes in Contraction
		Nervous Tissue Detects and Responds to Changes in the Environment
		Cell Junctions Connect Adjacent Cells
	Critical Thinking
	From Research to Reality
4 Metabolism
	4.1 An Overview of Metabolism
	4.2 Energy and Metabolism
		Energy Exists in Different Forms
		Chemical Reactions Release or Absorb Energy
		Activation Energy Is Needed to Start a Chemical Reaction
		Catalysts Lower the Activation Energy of Chemical Reactions
	4.3 Enzymes
		Enzymes Have Important Properties
		Enzymes Catalyze Reactions by Helping Molecules Interact
		Many Enzymes Require a Cofactor in Order to Function
		Various Factors Influence the Rate of an Enzyme-Catalyzed Reaction
		A Sequence of Enzymatic Reactions Constitutes a Metabolic Pathway
		Metabolic Pathways Are Shut down by Feedback Inhibition
	4.4 Role of ATP in Metabolism
		Catabolism and Anabolism Are Coupled by ATP
		ATP Is Generated via Substrate-Level Phosphorylation and Oxidative Phosphorylation
		NAD+ and FAD Help Generate ATP by Carrying Hydrogen Atoms to the Electron Transport Chain
		Cellular Respiration Produces ATP by Breaking Down a Nutrient Molecule in the Presence of Oxygen
	4.5 Carbohydrate Metabolism
		Glucose Catabolism Can Generate 30 or 32 ATP
		Glucose Anabolism Includes Glycogenesis and Gluconeogenesis
	4.6 Lipid Metabolism
		Lipid Catabolism Involves Lipolysis and Beta Oxidation
		Lipid Anabolism Occurs via Lipogenesis
	4.7 Protein Metabolism
		Protein Catabolism Leads to Deamination and Keto Acid Breakdown
		Protein Anabolism Results in the Synthesis of New Proteins
	4.8 Nutrition and Metabolism
		Many Minerals Have Known Functions in the Body
		Vitamins Help Maintain Growth and Normal Metabolism
	Critical Thinking
	From Research to Reality
5 Transport Across the Plasma Membrane
	5.1 Selective Permeability of the Plasma Membrane
	5.2 Gradients Across the Plasma Membrane
	5.3 Classification of Membrane Transport Processes as Passive or Active
	5.4 Passive Transport
		Diffusion Relies on the Kinetic Energy That Is Intrinsic to All Particles
		Simple Diffusion Occurs When a Solute Moves down Its Gradient Without Any Help
		Facilitated Diffusion Uses a Protein to Move a Solute down Its Gradient
		Osmosis Results in Net Movement of Water Across a Selectively Permeable Membrane
	5.5 Active Transport
		Primary Active Transport Uses Energy from ATP to Move a Solute Against Its Gradient
		Secondary Active Transport Uses Energy from an Ionic Gradient to Move a Solute Against Its Gradient
	5.6 Vesicular Transport
		Endocytosis Allows Ligands, Large Solid Particles, and Droplets of Extracellular Fluid to Enter Cells
		Exocytosis Is Used to Release Digestive Enzymes, Hormones, and Neurotransmitters from Certain Cells
	5.7 Transepithelial Transport
	Critical Thinking
	From Research to Reality
6 Cell Signaling
	6.1 Methods of Cell-to-Cell Communication
		Gap Junctions Electrically Couple Cells Together
		Cell-to-Cell Binding Is Important for Development and Defense
		Communication Through Extracellular Chemical Messengers Permits a Wide Variety of Responses
	6.2 Extracellular Chemical Messengers
		Different Types of Extracellular Chemical Messengers Exist
		Extracellular Messengers Are Chemically Classified as Water-Soluble or Lipid-Soluble
		Extracellular Messengers Travel Through Interstitial Fluid and/or Blood to Reach Their Target Cells
	6.3 Receptors
		Messenger–Receptor Binding Exhibits Several Properties
		Receptors Are Located in the Target Cell’s Plasma Membrane or Inside the Target Cell
		Receptors Are Subject to Down-Regulation and Up-Regulation
	6.4 Signal Transduction Pathways
		Signal Transduction Begins with Binding of Messenger and Ends with a Cellular Response
		Lipid-Soluble Extracellular Messengers Activate Signaling Pathways by Binding to Intracellular Receptors
		Water-Soluble Extracellular Messengers Activate Signaling Pathways by Binding to Plasma Membrane Receptors
		Signal Amplification Promotes a Greater Cellular Response
		Signal Termination Prevents Overstimulation of the Target Cell
	6.5 Comparison of the Nervous and Endocrine Systems
	Critical Thinking
	From Research to Reality
7 The Nervous System and Neuronal Excitability
	7.1 Overview of the Nervous System
		The Nervous System Is Organized into the Central Nervous System and the Peripheral Nervous System
		The Nervous System Performs Sensory, Integrative, and Motor Functions
	7.2 Cells of the Nervous System
		Neurons Are Responsible for the Main Functions of the Nervous System
		Neuroglia Provide Physical, Nutritional, and Metabolic Support to Neurons
		Myelination Increases the Speed of Action Potential Conduction
		Damaged Neurons Have a Limited Ability to Repair Themselves
	7.3 Electrical Signals in Neurons
		Ion Channels Permit Certain Ions to Move Across the Plasma Membrane
		Resting Membrane Potential Is the Voltage That Exists Across the Plasma Membrane in an Excitable Cell at Rest
		Graded Potentials Can Be Depolarizing or Hyperpolarizing
		Action Potentials Are Generated When the Axon Membrane Reaches Threshold
		Action Potentials Undergo Propagation
		The Extracellular Concentrations of Several Ions Influence Neuronal Excitability
	7.4 Signal Transmission at Synapses
		Electrical Synapses Involve Gap Junctions
		Chemical Synapses Involve the Release of Neurotransmitter into a Synaptic Cleft
		Neurotransmitters Excite or Inhibit the Postsynaptic Cell
		There Are Two Main Types of Neurotransmitter Receptors: Ionotropic and Metabotropic
		Neurotransmitter Can Be Removed in Different Ways
		Postsynaptic Potentials Are Summated
		Presynaptic Modulation Regulates Neurotransmitter Release
	7.5 Neurotransmitters
		There Are Several Types of Small-Molecule Neurotransmitters
		Neuropeptides Are Composed of Amino Acids Linked by Peptide Bonds
	7.6 Neural Circuits
	Critical Thinking
	From Research to Reality
8 The Central Nervous System
	8.1 Spinal Cord
		The Spinal Cord Is Protected by Vertebrae and Meninges
		Spinal Nerves Link the Spinal Cord to Sensory Receptors and Effectors
		The Internal Organization of the Spinal Cord Allows Processing of Sensory Input and Motor Output
		The Spinal Cord Propagates Signals Along Sensory and Motor Tracts and Coordinates Reflexes
	8.2 Brain
		The Brain Is Protected in Many Ways
		The Brain Depends on a Continuous Supply of Oxygen and Glucose by the Blood
		Cranial Nerves Link the Brain to Sensory Receptors and Effectors
		The Different Parts of the Brain Perform a Variety of Functions
	8.3 Integrative Functions of the Cerebrum
		Wakefulness and Sleep Involve Multiple Areas of the Brain
		Language Is an Important Form of Communication
		Emotions Can Trigger Autonomic and Somatic Motor Responses
		Motivation Is Promoted by the Mesolimbic Dopamine Pathway
		Learning and Memory Allow Us to Acquire, Store, and Recall Information
	Critical Thinking
	From Research to Reality
9 Sensory Systems
	9.1 Overview of Sensation
		The Process of Sensation Involves Four Events
		There Are Different Types of Sensory Receptors
		Sensory Neurons Have Receptive Fields
		Sensory Coding Distinguishes the Attributes of a Stimulus
		A Sensory Pathway Conveys Sensory Information
	9.2 The Somatic Sensory System
		Tactile Sensations Allow Us to Feel Touch, Pressure, Vibration, Itch, and Tickle
		Thermal Sensations Provide Information About How Hot or Cold the Skin Is
		Pain Sensations Protect the Body from Stimuli That Can Cause Tissue Damage
		Proprioceptive Sensations Provide Information About Muscle and Joint Position
		Two Major Pathways Convey Somatic Sensory Input to the Primary Somatosensory Cortex
		The Primary Somatosensory Cortex Allows Precise Localization of Somatic Sensory Stimuli
		The Somatosensory Association Area Permits Recognition of Somatic Sensory Stimuli
		Visceral Sensations Provide Input About Internal Conditions
	9.3 The Olfactory System
		The Olfactory Epithelium Contains the Receptors for Smell
		Olfactory Transduction Converts an Olfactory Stimulus into a Receptor Potential
		The Olfactory Pathway Extends from Olfactory Receptors to the Olfactory Areas of the Brain
		The Threshold for Detecting Odors Is Low
		The Olfactory System Rapidly Adapts
	9.4 The Gustatory System
		Taste Buds Contain the Receptors for Taste
		Taste Transduction Converts a Gustatory Stimulus into a Receptor Potential
		The Gustatory Pathway Extends from Taste Receptors to the Gustatory Cortex
		The Threshold for Detecting Taste Can Vary
		Taste Adaptation Occurs at Many Levels
	9.5 The Visual System
		Visible Light Is the Part of the Electromagnetic Spectrum That the Eye Can Detect
		Accessory Structures Protect, Lubricate, and Move the Eye
		The Eye Consists of Several Functional Components
		The Eye Forms Images of Objects on the Retina
		Convergence of the Eyes Maintains Binocular Vision
		Two Types of Photoreceptors Are Required for Normal Vision
		Both Eyes Receive Input from the Left and Right Visual Fields
		The Visual Pathway Extends from Photoreceptors to the Visual Areas of the Brain
		The Primary Visual Cortex Perceives Light
		The Visual Association Area Performs Several Functions
		The Visual System Can Undergo Light and Dark Adaptation
	9.6 The Auditory and Vestibular Systems
		The Ear Has Different Functional Components
		Sound Waves Are Generated from a Vibrating Object
		Transmission of Sound Waves Through the Ear Involves Several Steps
		Inner Hair Cells Are Responsible for Sound Transduction
		Outer Hair Cells Enhance the Sensitivity of Inner Hair Cells
		Pitch Discrimination Depends on Which Region of the Basilar Membrane Vibrates
		Loudness Discrimination Depends on How Much the Basilar Membrane Vibrates
		The Auditory Pathway Conveys Sound Input to the Auditory Cortex
		The Primary Auditory Cortex Perceives Sound
		The Auditory Association Area Allows You to Recognize a Sound
		Deafness Results from Defects in the Conductive or Neural Pathways Associated with the Ear
		Equilibrium Is the Sense of Balance
		The Otolithic Organs Detect Linear Acceleration or Deceleration and Head Tilt
		The Semicircular Ducts Detect Rotational Acceleration or Deceleration
		Equilibrium Pathways Convey Vestibular Input to Different Parts of the Brain
	Critical Thinking
	From Research to Reality
10 Autonomic and Somatic Nervous Systems
	10.1 Autonomic Nervous System
		The Autonomic Nervous System Regulates the Activity of Smooth Muscle, Cardiac Muscle, and Glands
		An Autonomic Motor Pathway Is Comprised of Two Autonomic Motor Neurons and a Visceral Effector
		The Neuroeffector Junction Is the Site Where an Autonomic Postganglionic Neuron Communicates with a Visceral Effector
		The Autonomic Nervous System Uses Different Types of Neurotransmitters and Receptors
		The Autonomic Nervous System Performs a Variety of Functions
		Autonomic Reflexes Help Maintain Homeostasis
		Autonomic Control Centers Are Present in the Brain and Spinal Cord
		Some Autonomic Responses Can Be Voluntarily Controlled via Biofeedback
	10.2 Somatic Nervous System
		The Somatic Nervous System Regulates the Activity of Skeletal Muscle
		A Somatic Motor Pathway Is Comprised of a Somatic Motor Neuron and Skeletal Muscle
		The Neuromuscular Junction Is the Site Where a Somatic Motor Neuron Communicates with a Skeletal Muscle Fiber
		The Events at the NMJ Can Be Altered by Chemicals
	Critical Thinking
	From Research to Reality
11 Muscle
	11.1 Overview of Muscle
		Three Types of Muscle Exist in the Body
		Muscle Performs a Variety of Functions
		Muscle Has Several Important Properties
	11.2 Organization of Skeletal Muscle
		The Components of a Skeletal Muscle Fiber Allow Contraction to Occur
		There Are Three Types of Muscle Proteins
	11.3 Contraction and Relaxation of Skeletal Muscle Fibers
		Muscle Contraction Occurs by the Sliding Filament Mechanism
		The Contraction Cycle Involves Four Major Steps
		The Neuromuscular Junction Is the Synapse Between a Somatic Motor Neuron and a Skeletal Muscle Fiber
		The Skeletal Muscle Action Potential Has Two Main Phases: A Depolarizing Phase and a Repolarizing Phase
		Excitation–Contraction Coupling in Skeletal Muscle Links the Muscle Action Potential to Muscle Contraction
		Skeletal Muscle Relaxes in Response to a Decrease in the Sarcoplasmic Ca2+ Concentration
	11.4 ATP Production in Skeletal Muscle
		Creatine Phosphate Is the First Source of ATP During Muscle Contraction
		Anaerobic Glycolysis Produces ATP When Oxygen Levels Are Low
		Aerobic Respiration Generates ATP When Sufficient Oxygen Is Available
		Several Factors Contribute to Muscle Fatigue
		Oxygen Consumption Increases for a While After Exercise
	11.5 Skeletal Muscle Mechanics
		A Motor Unit Is Comprised of a Somatic Motor Neuron and Its Muscle Fibers
		A Muscle Twitch Consists of Latent, Contraction, and Relaxation Periods
		Graded Contractions Can Occur in Skeletal Muscle
		Numerous Factors Determine Muscle Tension
		Muscle Tone Is Established by Different Motor Units That Are Alternately Active and Inactive
		Movement Involves the Interaction of Skeletal Muscles, Tendons, and Bones
		There Are Two Major Categories of Muscle Contractions: Isotonic and Isometric
	11.6 Types of Skeletal Muscle Fibers
		Slow Oxidative Fibers Have a High Resistance to Fatigue
		Fast Oxidative–Glycolytic Fibers Have a Moderate Resistance to Fatigue
		Fast Glycolytic Fibers Have a Low Resistance to Fatigue
		The Three Types of Skeletal Muscle Fibers Are Distributed Differently and Recruited in a Certain Order
		Exercise Can Induce Changes in the Different Types of Skeletal Muscle Fibers
	11.7 Cardiac Muscle
	11.8 Smooth Muscle
		The Components of a Smooth Muscle Fiber Allow Considerable Tension to Develop During Contraction
		Contraction and Relaxation Occur More Slowly in Smooth Muscle Than in Striated Muscle
		Smooth Muscle Tone Allows Maintenance of Steady Pressure
		The Autonomic Nervous System Regulates Smooth Muscle
		Two Forms of Smooth Muscle Exist: Single-Unit and Multi-Unit
		Smooth Muscle Can Exhibit Autorhythmicity
		Contractile Smooth Muscle Fibers Can Produce Action Potentials When Excited by Autorhythmic Signals or Other Stimuli
		Excitation–Contraction Coupling in Smooth Muscle Involves Several Mechanisms
		Several Factors Can Regulate Smooth Muscle Activity
		The Stress–Relaxation Response Allows Changes in Smooth Muscle Length Without Affecting the Ability to Contract
		Smooth Muscle Produces ATP by Aerobic Respiration and Anaerobic Glycolysis
	11.9 Regeneration of Muscle
	Critical Thinking
	From Research to Reality
12 Control of Body Movement
	12.1 Overview of Motor Control
		Lower Motor Neurons Provide Output from the CNS to Skeletal Muscle Fibers
		There Are Four Sources of Input to Lower Motor Neurons
	12.2 Local Level of Motor Control
		Somatic Reflexes Allow Fast, Involuntary Contractions of Skeletal Muscle
		Central Pattern Generators Are Responsible for Locomotion
	12.3 Control of Movement by the Cerebral Cortex
		The Premotor Cortex Creates a Motor Plan
		The Primary Motor Cortex Controls the Execution of Voluntary Movements
		The Primary Motor Cortex Gives Rise to the Direct Motor Pathways
	12.4 Control of Movement by the Brain Stem
		Brain Stem Motor Centers Give Rise to the Indirect Motor Pathways
		The Vestibular Nuclei Help Control Posture in Response to Changes in Balance
		The Reticular Formation Helps Regulate Posture and Muscle Tone During Ongoing Movements
		The Superior Colliculus Promotes Reflexive Movements of the Head and Trunk and Saccadic Eye Movements
		The Red Nucleus Helps Control Voluntary Movements of the Upper Limbs
	12.5 The Basal Nuclei and Motor Control
	12.6 Modulation of Movement by the Cerebellum
	Critical Thinking
	From Research to Reality
13 The Endocrine System
	13.1 Overview of the Endocrine System
		The Endocrine System Consists of All Glands, Organs, and Tissues That Contain Hormone-Secreting Cells
		Hormones Influence Target Cells by Binding to Receptors
		Hormones Are Chemically Classified as Lipid-Soluble or Water-Soluble
		Hormones Circulate Through the Blood in Free Form or Bound to Transport Proteins
		A Hormone’s Mechanism of Action Depends on the Signaling Pathway That It Activates
		Hormones Can Have Permissive, Synergistic, or Antagonistic Effects
		Hormone Secretion Is Controlled in a Variety of Ways
	13.2 Pituitary Gland
		The Anterior Pituitary Secretes Many Hormones
		The Posterior Pituitary Releases Oxytocin and Antidiuretic Hormone
	13.3 Thyroid Gland
		Thyroid Follicles Form, Store, and Release Thyroid Hormones
		Thyroid Hormones Increase Basal Metabolic Rate and Have Other Effects
		Secretion of Thyroid Hormones Is Regulated by the Hypothalamus and Anterior Pituitary
		Calcitonin Lowers the Blood Calcium Level
	13.4 Parathyroid Glands
	13.5 Adrenal Glands
		The Adrenal Cortex Consists of Three Zones That Secrete Hormones
		The Adrenal Medulla Is an Extension of the Sympathetic Nervous System That Secretes Hormones
	13.6 Pineal Gland
	13.7 Pancreas
		The Pancreas Secretes Several Hormones, Including Insulin and Glucagon
		Insulin Stimulates Uptake of Glucose, Fatty Acids, and Amino Acids and Synthesis of Glycogen, Triglycerides, and Proteins
		Glucagon Has Functions That Are Antagonistic to Those of Insulin
		Insulin and Glucagon Secretion Are Regulated by the Blood Glucose Concentration and Other Factors
	13.8 Ovaries and Testes
	13.9 Other Endocrine Organs and Tissues
		The Skin Secretes Cholecalciferol
		The Thymus Secretes Hormones That Promote Immune Function
		The Heart Secretes Atrial Natriuretic Peptide
		The Liver Produces Two Hormones
		The Stomach and Small Intestine Secrete Hormones That Regulate Digestive Activities
		The Kidneys Secrete Calcitriol and Erythropoietin
		Adipose Tissue Secretes Leptin
		The Placenta Secretes Several Hormones That Help Maintain Pregnancy and Prepare the Maternal Body for Birth
	13.10 Endocrine Control of Growth
		Bones Grow in Length and in Thickness
		Bones Undergo Remodeling
		Several Hormones Affect Bone Growth
		Factors Other Than Hormones Also Influence Bone Growth
	13.11 The Stress Response
		The Fight-or-Flight Response Allows the Body to Handle Stress Quickly
		The Resistance Reaction Provides a Longer-lasting Response to Stress
		After the Resistance Reaction Is Exhaustion
		Stress Can Lead to Disease
	Critical Thinking
	From Research to Reality
14 The Cardiovascular System: The Heart
	14.1 Basic Design of the Cardiovascular System
		The Heart Pumps Blood Through the Pulmonary and Systemic Circulations
		Blood Is Distributed in the Systemic Circulation Mainly via Parallel Flow
	14.2 Organization of the Heart
		The Pericardium Protects and Anchors the Three-Layered Heart
		The Heart Contains Four Chambers and Is Associated with Several Great Vessels
		Heart Valves Ensure One-Way Blood Flow
		The Fibrous Skeleton of the Heart Prevents Overstretching of Heart Valves
		The Coronary Circulation Supplies Blood to the Heart Wall
	14.3 Cardiac Muscle Tissue and the Cardiac Conduction System
		Interconnected Cardiac Muscle Fibers Act as a Functional Syncytium
		The Conduction System of the Heart Ensures Coordinated Contraction
		Contractile Fibers Produce Action Potentials in Response to Autorhythmic Fibers
		Excitation–Contraction Coupling Links Cardiac Action Potentials to Cardiac Contraction
		Cardiac Muscle Fibers Have a Long Refractory Period
		Cardiac Muscle Produces ATP via Aerobic Respiration
		The Electrocardiogram Records Electrical Signals Generated by the Heart
		ECG Waves Predict the Timing of Atrial and Ventricular Systole and Diastole
	14.4 The Cardiac Cycle
		The Cardiac Cycle Has Five Phases
		At Rest a Cardiac Cycle Lasts About 0.8 Seconds
		Two Major Heart Sounds Can Be Heard During Each Cardiac Cycle
	14.5 Cardiac Output
		Stroke Volume Is Regulated by Preload, Contractility, and Afterload
		Heart Rate Is Regulated Mainly by the ANS and Certain Chemicals
	14.6 Exercise and the Heart
	Critical Thinking
	From Research to Reality
15 The Cardiovascular System: Blood Vessels and Hemodynamics
	15.1 Overview of the Vasculature
		The Layers of a Blood Vessel Contribute to Vessel Function
		Arteries Carry Blood Away from the Heart
		Arterioles Deliver Blood to Capillaries
		Capillaries Are the Sites of Nutrient and Waste Exchange
		Venules Drain Blood from Capillaries
		Veins Carry Blood back to the Heart
		Systemic Veins and Venules Function as Blood Reservoirs
	15.2 Capillary Exchange and Lymphatics
		Diffusion Is the Most Important Method of Capillary Exchange
		Transcytosis Allows Transport of Large Molecules Across Capillary Walls
		Bulk Flow Regulates the Relative Volumes of Blood and Interstitial Fluid
		The Lymphatic System Begins in the Tissues Close to Blood Capillaries
	15.3 Hemodynamics
		Blood Flow Is Affected by Pressure and Resistance
		Blood Flow Through Blood Vessels Can Be Laminar or Turbulent
		Blood Pressure Is Hydrostatic Pressure Exerted by Blood on Blood Vessel Walls
		Vascular Compliance Is High in Veins and Low in Arteries
		Velocity of Blood Flow Is Inversely Proportional to the Cross-Sectional Area
		Venous Return Brings Blood Back to the Heart
	15.4 Control of Blood Flow
		Intrinsic Control of Blood Flow Includes Physical Changes and Local Mediators
		Extrinsic Control of Blood Flow Includes Nerves and Hormones
	15.5 Regulation of Mean Arterial Pressure
		The Nervous System Is an Important Regulator of Mean Arterial Pressure
		Hormones Also Regulate Mean Arterial Pressure
	15.6 Shock and Homeostasis
		There Are Four Types of Shock
		The Body’s Response to Shock Involves Several Compensatory Mechanisms
		Shock Has Many Signs and Symptoms
	Critical Thinking
	From Research to Reality
16 The Cardiovascular System: The Blood
	16.1 Overview of Blood
		Blood Performs Important Functions in the Body
		Plasma and Cellular Elements Are the Two Main Components of Blood
		Blood Cells Are Formed in Bone Marrow
	16.2 Erythrocytes
		Erythrocytes Transport Oxygen and Carbon Dioxide
		Erythrocytes Are Produced via Erythropoiesis
		The Erythrocyte Life Cycle Is About 120 Days
	16.3 Leukocytes
		The Five Types of Leukocytes Are Grouped into Two Categories
		Leukocytes Defend the Body Against Invading Pathogens and Abnormal Cells
		Leukocytes Are Produced via Leukopoiesis
	16.4 Platelets
	16.5 Hemostasis
		Vascular Spasm Occurs Immediately After Vessel Injury
		A Platelet Plug Is a Mass of Platelets That Accumulates at the Site of Injury
		Blood Clotting Results in the Formation of Fibrin Threads at the Injured Area
	16.6 Blood Groups and Blood Types
		The ABO Blood Group Is Determined by the Presence or Absence of A and B Antigens
		An Incompatible Transfusion Causes Agglutination
		The Rh Blood Group Is Based on the Presence or Absence of Rh Antigens
	Critical Thinking
	From Research to Reality
17 The Immune System
	17.1 Components of the Immune System
		The Cells of the Immune System Include Leukocytes, Mast Cells, and Dendritic Cells
		There Are Several Types of Lymphoid Organs and Tissues
	17.2 Innate Immunity
		The First Line of Defense Consists of the External Physical and Chemical Barriers of the Body
		The Second Line of Defense Is Comprised of Various Internal Defenses
	17.3 Adaptive Immunity
		B Cells and T Cells Are Important Components of Adaptive Immunity
		Adaptive Immunity Can Be Mediated by Cells or Antibodies
		Clonal Selection Increases the Number of B Cells and T Cells that Can Respond to an Antigen
		Antigens Trigger Immune Responses
		Major Histocompatibility Complex Proteins Are Types of Self-Antigens
		Antigens Are Processed and Then Presented
		Cytokines Have Important Roles in Immunity
		Cell-Mediated Immunity Uses T Cells to Eliminate Specific Antigens
		Antibody-Mediated Immunity Uses Antibodies to Inactivate Specific Antigens
		Immunological Memory Allows the Immune System to Remember Previously Encountered Antigens
		There Are Four Ways to Acquire Adaptive Immunity
		Self-Recognition and Self-Tolerance Prevent the Immune System from Attacking the Body’s Own Tissues
		Allergic Reactions May Be Immediate or Delayed
	Critical Thinking
	From Research to Reality
18 The Respiratory System
	18.1 Overview of the Respiratory System
		Respiration Supplies the Body with O2 and Removes CO2
		The Respiratory System Is Comprised of Several Organs
		The Respiratory Mucosa Produces Mucus That Traps Particles and Lubricates the Airways
		The Nose Brings Air into the Respiratory System
		The Pharynx Is a Common Passageway for Air and Food
		The Larynx Routes Air and Food into the Proper Channels and Also Causes Vocalization
		The Trachea Carries Air to the Primary Bronchi
		The Primary Bronchi Transport Air to the Lungs
		The Lungs Contain Most of the Components of the Respiratory System
		The Alveoli Are the Sites of Gas Exchange Between Air and Blood
		There Are Two Functional Zones of the Respiratory System
		The Pulmonary Circulation Has a High Rate of Flow, a Low Resistance, and a Low Pressure
	18.2 Ventilation
		The Breathing Cycle Has Three Phases
		Several Factors Affect Ventilation
		Ventilation and Perfusion of the Alveoli Are Matched for Optimal Gas Exchange
		There Are Different Patterns of Respiratory Movements
	18.3 Lung Volumes and Capacities
	18.4 Exchange of Oxygen and Carbon Dioxide
		Two Gas Laws—Dalton’s Law and Henry’s Law—Are Important for Understanding How Gas Exchange Occurs
		There Are Two Types of Gas Exchange: Pulmonary and Systemic
	18.5 Transport of Oxygen and Carbon Dioxide
		Oxygen Is Transported Through the Blood Mainly by Hemoglobin
		The PO2 Determines How Much Oxygen Binds to Hemoglobin
		Several Factors Affect the Affinity of Hemoglobin for Oxygen
		Fetal Hemoglobin and Adult Hemoglobin Have Different Affinities for Oxygen
		Carbon Dioxide Is Transported Through the Blood in Three Forms
		Gas Exchange and Transport Can Be Summarized
	18.6 Control of Ventilation
		The Respiratory Center Controls Breathing
		The Respiratory Center Is Subject to Regulation
	18.7 Exercise and the Respiratory System
	Critical Thinking
	From Research to Reality
19 The Urinary System
	19.1 Overview of Kidney Functions
	19.2 Organization of the Kidneys
		Nephrons Perform the Main Functions of the Kidneys
		The Extensive Blood Supply of the Kidneys Contributes to Renal Function
		The Juxtaglomerular Apparatus Consists of Part of the Distal Tubule and Afferent Arteriole
	19.3 Overview of Renal Physiology
	19.4 Glomerular Filtration
		The Renal Corpuscle Contains a Filtration Membrane
		Glomerular Filtration Is Determined by the Balance of Four Pressures
		The Glomerular Filtration Rate Is an Important Aspect of Kidney Function
		The Glomerular Filtration Rate Is Regulated in Different Ways
	19.5 Tubular Reabsorption and Tubular Secretion
		There Are Two Types of Reabsorption Routes: Paracellular and Transcellular
		Transport of Substances Across the Tubular Wall Often Involves the Use of Transport Proteins
		Water Reabsorption May Be Obligatory or Facultative
		Different Substances Are Reabsorbed or Secreted to Varying Degrees in Different Parts of the Renal Tubule and Collecting Duct
		Tubular Reabsorption and Tubular Secretion Are Subject to Hormonal Regulation
	19.6 Production of Dilute and Concentrated Urine
		The Production of Dilute Urine Allows the Kidneys to Get Rid of Excess Water
		The Production of Concentrated Urine Allows the Kidneys to Conserve Water
	19.7 Evaluation of Kidney Function
		A Urinalysis Examines the Various Properties of Urine
		Blood Tests for Renal Function Include the Blood Urea Nitrogen Test and Measurement of Plasma Creatinine
		Renal Plasma Clearance Indicates How Effectively the Kidneys Are Removing a Substance from Blood Plasma
		Renal Failure Occurs Because of Inadequate Kidney Function
	19.8 Urine Transportation, Storage, and Elimination
		The Ureters Carry Urine to the Urinary Bladder
		The Urinary Bladder Stores Urine
		The Urethra Conveys Urine to the Outside Environment
	19.9 Waste Management in Other Body Systems
	Critical Thinking
	From Research to Reality
20 Fluid, Electrolyte, and Acid–Base Homeostasis
	20.1 Fluid Compartments and Fluid Balance
		The Body Can Gain or Lose Water
		Body Water Gain Is Regulated Mainly by the Volume of Water Intake
		Body Water or Solute Loss Is Regulated Mainly by Control of Their Loss in Urine
		Water Can Move Between Body Fluid Compartments
	20.2 Electrolytes in Body Fluids
		The Electrolyte Concentrations in Body Fluids Can Be Measured in Milliequivalents per Liter
		Electrolytes Perform Many Functions in the Body
	20.3 Acid–Base Balance
		Buffer Systems Convert Strong Acids and Bases into Weak Acids and Bases
		Exhalation of Carbon Dioxide Helps Eliminate H+ Ions
		The Kidneys Remove H+ Ions by Excreting Them into Urine
		There Are Different Types of Acid–Base Imbalances
	Critical Thinking
	From Research to Reality
21 The Digestive System
	21.1 Overview of the Digestive System
		The Digestive System Consists of the Gastrointestinal Tract and the Accessory Digestive Organs
		There Are Six Basic Digestive Processes
		The Wall of the GI Tract Is Comprised of Four Functional Layers
		The GI Tract Has Neural Innervation
		GI Smooth Muscle Is Autorhythmic and Promotes Two Major Patterns of Motility
	21.2 Mouth
		The Cheeks and Lips Keep Food in the Mouth During Chewing
		The Palate Prevents Food from Entering the Nasal Cavity
		The Tongue Moves Food Toward the Pharynx and Produces Lingual Lipase
		The Salivary Glands Secrete Saliva
		The Teeth Physically Break Down Food
		Mechanical Digestion in the Mouth Involves Chewing
		Chemical Digestion in the Mouth Occurs as Food Mixes with Saliva
	21.3 Pharynx and Esophagus
		The Pharynx Conveys Food from the Mouth to the Esophagus
		The Esophagus Transports Food to the Stomach
		Deglutition Is the Process by Which Food Is Swallowed
	21.4 Stomach
		Mechanical Digestion in the Stomach Involves Propulsion and Retropulsion
		Chemical Digestion in the Stomach Occurs as Food Mixes with Gastric Juice
		Vomiting Rapidly Expels the Contents of the GI Tract
	21.5 Pancreas, Liver, and Gallbladder
		The Pancreas Secretes Pancreatic Juice
		The Liver Secretes Bile and Performs Many Other Functions
		The Gallbladder Stores and Concentrates Bile
	21.6 Small Intestine
		The Small Intestine Secretes Intestinal Juice
		Brush-Border Enzymes Are Attached to the Microvilli of Small Intestinal Absorptive Cells
		Mechanical Digestion in the Small Intestine Involves Segmentation and the Migrating Motility Complex
		Chemical Digestion in the Small Intestine Occurs as Chyme Mixes with Intestinal Juice, Pancreatic Juice, and Bile
		Most Nutrients and Water Are Absorbed in the Small Intestine
	21.7 Large Intestine
		Mechanical Digestion in the Large Intestine Involves Haustral Churning, Peristalsis, and Mass Movement
		Chemical Digestion in the Large Intestine Occurs via Bacteria
		Feces Are Formed in the Large Intestine
		The Defecation Reflex Expels Feces from the Body
	21.8 Phases of Digestion
		The Cephalic Phase Prepares the Mouth and Stomach for Food That Is About to Be Eaten
		The Gastric Phase Promotes Gastric Juice Secretion and Gastric Motility
		The Intestinal Phase Promotes Digestion in the Small Intestine and Slows Digestion in the Stomach
		There Are Many Hormones of the Digestive System
	21.9 Transport of Lipids by Lipoproteins
	Critical Thinking
	From Research to Reality
22 Metabolic Adaptations, Energy Balance, and Temperature Regulation
	22.1 Metabolic Adaptations
		The Absorptive State Promotes Reactions That Catabolize Nutrients, Synthesize Proteins, and Form Nutrient Stores
		The Postabsorptive State Promotes Reactions That Maintain the Normal Blood Glucose Level When the GI Tract Lacks Nutrients
		Metabolism During Fasting and Starvation Results in an Increase in Ketone Body Formation
	22.2 Energy Balance
		The Energy Content in Food Is Expressed in Units Called Calories
		The Metabolic Rate Reflects the Amount of Energy Used by Metabolic Reactions over Time
		Adipose Tissue Is the Main Site of Stored Chemical Energy
		Food Intake Is Regulated by Many Factors
		Obesity Occurs When Too Much Adipose Tissue Accumulates in the Body
	22.3 Regulation of Body Temperature
		There Are Four Mechanisms of Heat Transfer
		The Hypothalamus Contains the Body’s Thermostat
		Thermoregulation Maintains the Body’s Temperature
	Critical Thinking
	From Research to Reality
23 The Reproductive Systems
	23.1 Reproductive Cell Division
		Somatic Cells and Gametes Have Different Numbers of Chromosomes
		There Are Two Stages of Meiosis
	23.2 Male Reproductive System
		The Scrotum Protects the Testes and Regulates Their Temperature
		The Testes Produce Sperm and Secrete Hormones
		The Male Duct System Aids in the Maturation, Storage, and Transport of Sperm
		The Accessory Sex Glands Add Secretions to Sperm to Form Semen
		The Penis Is the Male Organ of Copulation
		Male Reproductive Function Is Regulated by Several Hormones
	23.3 Female Reproductive System
		The Ovaries Produce Eggs and Secrete Hormones
		The Fallopian Tube Transports an Egg from the Ovary to the Uterus
		The Uterus Has Many Reproductive Functions
		The Vagina Is the Female Organ of Copulation
		The Vulva Refers to the Female External Genitalia
		The Mammary Glands Function in Lactation
		Female Reproductive Function Is Regulated by Many Hormones
		The Female Reproductive Cycle Refers to the Cyclical Changes in the Ovaries and Uterus
	23.4 The Human Sexual Response
	23.5 Sex Determination and Sex Differentiation
		Sex Determination Is Based on the Types of Sex Chromosomes That Are Present
		Sex Differentiation Involves Sex Chromosomes and the Presence or Absence of Certain Hormones
	23.6 Aging and the Reproductive Systems
	23.7 Pregnancy and Labor
		The Embryonic Period Involves Several Important Events
		The Fetal Period Is a Time of Growth and Differentiation
		The Extraembryonic Membranes Have Ancillary Developmental Roles
		The Decidua Refers to the Stratum Functionalis of the Uterus in a Pregnant Woman
		The Placenta Is the Site of Nutrient and Waste Exchange Between the Mother and Fetus and Has Other Important Functional Roles
		Teratogens Cause Developmental Defects in the Embryo or Fetus
		Labor Involves Complex Hormonal Interactions and Occurs in Three Stages
		Lactation Is the Process by Which the Mammary Glands Produce and Eject Milk
	23.8 Contraception and Abortion
		Various Methods of Contraception Control Fertility and Prevent Conception
		Abortion Results in the Termination of a Pregnancy
	23.9 Infertility
	Critical Thinking
	From Research to Reality
Appendix A: Measurements
Appendix B: Periodic Table
Appendix C: Normal Values for Selected Blood Tests
Appendix D: Normal Values for Selected Urine Tests
Glossary
Index
EULA