anatomy

Study Unit

Anatomy andPhysiology

A body system is composed of organs that are designed to worktogether so that a particular functionsuch as breathingcanbe performed. Even though each minute part of each systemfrom cell to tissue to muscle to bonehas its own specific job todo, the various body parts must also work smoothly together.

When you complete your work in this study unit, youll haveexpanded your understanding of medical terminology to includethe anatomy, pathology, procedures, and abbreviations asso-ciated with the nervous, sensory, circulatory, respiratory, andmusculoskeletal systems.

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Previe

wPrevie

wWhen you complete this study unit, youll beable to

Identify and explain the functions of the major structuresof the nervous, sensory, circulatory, respiratory, andmusculoskeletal systems

Identify and define terms related to diseases, diagnosis,and treatment of diseases of the nervous, sensory, circulatory, respiratory, and musculoskeletal systems

Use combining forms to build and analyze terms relatedto the nervous, sensory, circulatory, respiratory, andmusculoskeletal systems

Remember to regularly check My Courses on your student homepage.

Your instructor may post additional resources that you can access to

enhance your learning experience.

Previewiv

HOW TO USE THIS UNIT

In this study unit, the phonetic spelling of each new medicalterm is listed in parentheses after the term. A phonetic spellingspells the word as it actually sounds. Practice saying the wordwhen you read it.

The phonetic spelling for each medical term is presented inthe simplest form possible. Use the following guidelines whenyou read each term out loud:

1. Long vowel sounds are marked with a straight bar overthem. Therefore, the phonetic spelling of hate is hat, thephonetic spelling of bee is be, the phonetic spelling oftime is tm, and so on.

2. Short vowel sounds are marked with a breve () overthem. Therefore, the phonetic spelling of hat is hat, thephonetic spelling of hen is hen, the phonetic spelling ofhit is ht, and so on.

3. Primary () and secondary () accents are marked assuch. The primary accent is the one thats stressed themost. For example, a common medical term, dentist, hastwo short vowels and is accented on the first part of theword; the phonetic spelling of the word is dentst. Theword is pronounced DEN-tist. The phonetic spelling for theword cardiac is karde-ak, and the word is pronouncedCAR-di-ac.

Each medical term and its phonetic spelling are repeated inthe pronunciation guide at the back of this unit. Weve given themost common pronunciation. The phonetics may be differentin some dictionaries.

Mastering medical terminology isnt an easy task. Youll needpractice. Refer to the definitions for each term given in thisunit again and again until youre sure of the meaning of eachterm.

With practice and determination, you will master medical terminology and be on your way to a successful career!

vContents

Contents

PART 1: THE NERVOUS SYSTEM 1

INTRODUCTION 1

THE ANATOMY AND PHYSIOLOGY OF THE CENTRAL NERVOUS SYSTEM 2

The Brain 3The Spinal Cord 5

THE ANATOMY AND PHYSIOLOGY OF THEPERIPHERAL NERVOUS SYSTEM 6

Cranial Nerves 6Spinal Nerves 7

PATHOLOGY OF THE NERVOUS SYSTEM 8

Vascular Disorders 9Infections 10Degenerative and Movement Disorders 12Seizure Disorders 13Congenital Disorders 13Neoplastic Disorders 14

TESTS AND PROCEDURES OF THE NERVOUS SYSTEM 16

Laboratory Tests 17Radiology Tests and Clinical Procedures 18Surgical Procedures 18Pharmacology Related to the Nervous System 19

PART 2: THE SENSORY SYSTEM 21

INTRODUCTION 21

THE ANATOMY AND PHYSIOLOGY OF THE SENSE ORGANS 21

THE EYE 22

Parts of the Eye 22Accessories of the Eye 23

DISEASES OF THE EYE 23

Optical Defects of the Eye 23Organic Defects of the Eye 24

Contentsvi

CLINICAL PROCEDURES RELATED TO THE EYE 25

THE EAR 25

The External Ear 25The Middle Ear 26The Inner Ear 26

DISEASES OF THE EAR 26

Diseases of the Outer Ear 26Diseases of the Middle Ear 26Diseases of the Inner Ear 27The Loss of Hearing 27

CLINICAL PROCEDURES RELATED TO THE EAR 27

THE SENSE OF SMELL 28

THE SENSE OF TASTE 28

THE GENERAL SENSES 29

PART 3: THE CIRCULATORY SYSTEM 33

INTRODUCTION 33

THE ANATOMY AND PHYSIOLOGY OF THE CIRCULATORY SYSTEM 33

The Blood System 33Plasma 34Blood Cells 34The Vascular System 34The Heart 36The Lymphatic System 37

PATHOLOGY OF THE CIRCULATORY SYSTEM 38Pathology of the Blood 38Pathology of the Blood Vessels 39Heart Diseases 42Lymphatic Pathology 45Procedures of the Circulatory System 46

PART 4: THE RESPIRATORY SYSTEM 49

THE ANATOMY AND PHYSIOLOGY OF THE RESPIRATORY SYSTEM 49

Introduction 49The Nose 50The Pharynx 50The Larynx 50The Trachea 51The Bronchi 51The Lungs 51The Mucous Glands, Mucous Membranes,

and Mucus 52How the Respiratory System Works 52

DISEASES OF THE RESPIRATORY SYSTEM 55

Diseases of the Nose and Throat 55Diseases of the Trachea, Bronchi, and Lungs 58

TESTS AND PROCEDURES OF THE RESPIRATORY SYSTEM 64

PART 5: THE MUSCULOSKELETAL SYSTEM 67

THE ANATOMY AND PHYSIOLOGY OF THE SKELETON 67

Skeletal Divisions 67Structure of Bones 68Axial Skeleton Bones 69The Appendicular Skeleton 71

PATHOLOGY OF THE BONES 75

Infections 75Vitamin, Mineral, and/or Hormonal Deficiencies 76Neoplasms of the Bone 76Fractures 77Surgical Procedures 78

THE ANATOMY AND PHYSIOLOGY OF THE JOINTS 81

Types of Joint Structures 81Types of Movements 83

Contents vii

Contentsviii

PATHOLOGY OF THE JOINTS 85

PROCEDURES RELATED TO THE JOINTS 87

THE ANATOMY AND PHYSIOLOGY OF THE MUSCLE STRUCTURES 89

Types of Muscle 89Movements Produced by the Skeletal Muscles 90

PATHOLOGY OF THE MUSCLES AND TENDONS 91

Injury Disorders 91Diseases 91

PROCEDURES RELATED TO THE MUSCLES 92

SELF-CHECK ANSWERS 95

PRONUNCIATION GUIDE 101

1Part 1: The Nervous System

INTRODUCTION

Your nervous system is the most complex and sophisticatedbody system because it regulates and coordinates the rest of your body systems. It controls every function your body iscapableor incapableof doing. Some of these functions arevoluntary, such as running, jumping, and climbing. Otherfunctions are involuntary, such as breathing, digesting, andpumping blood. But no matter what the function is, all ofyour body systems depend upon the nervous system.

The nervous system (shown in Figure 1) has two parts:

1. The central nervous system (CNS), which consists of thebrain and the spinal cord

2. The peripheral nervous system (PNS), which consists ofthe cranial and spinal nerves

Anatomy and Physiology

Anatomy and Physiology2

THE ANATOMY ANDPHYSIOLOGY OF THECENTRAL NERVOUSSYSTEM

The central nervous system earned its namefrom its central location in the body, a goodlocation for a system that functions as communication headquarters for your body.Whether youre awake or not, the centralnervous system receives information, makesdecisions, and sends information to nerveslocated throughout your body every secondof the day. Every nerve pathwayno matterhow long (and some are up to six feetlong!)is connected at one end to the cen-tral nervous system.

The central nervous system is comprised ofthe two most important structures in thebodythe brain and the spinal cord. Becausethese delicate structures are vital to oursurvival, nature has provided them withtwo coveringsan outer covering of boneand an inner covering of membrane.

Two types of bone form the outer covering:

1. Cranial bone (kra ne-al), which encases the brain

2. Vertebrae (verte-bra), which encase the spinal cord

Three distinct layers of tissues, also known as meninges (me-nnjez), form the inner covering:

1. The dura mater (du rahma ter)

2. The arachnoid (ah-raknoid)

3. The pia mater (pahma ter)

FIGURE 1The Nervous System

Anatomy and Physiology 3

The Brain

Perhaps the least understood yet the most admired bodystructure is the brain. Its been estimated that people useonly 10 percent of the brains potential; the rest of its powerlies untapped.

The average human brain weighs about three pounds, andthe mass of wrinkled, sausage-like tissue contains millions of nerve cells and fibers. At any moment, millions of neuralmessages are flashing through your brain. Did you know, for instance, that you think at a rate of approximately 1,000words per minute? And words arent the only messages zip-ping through the brain; other information includes heartrate, blood pressure, respiration rate, temperature, muscletone, and blood chemistry.

Basically, though, the brain is a hollow organ that has cere-brospinal fluid-filled spaces called ventricles. And, althoughthe other body systems depend on the brain, the brain relieson them, too. Brain cells need a continuous supply of oxygenand glucose thats manufactured and/or delivered to thebrain through the cooperation of the respiratory, digestive,and vascular systems. If the brain is deprived of oxygen andglucose, it falls unconscious. Irreversible damage can occurwithin minutes.

The brain is divided into four major sections (Figure 2):

1. The cerebrum (sahre-brum)

2. The diencephalon (den-sefah-lon), which includes the hypothalamus (h-po-thalah-mus) and the thalamus (thalah-mus)

3. The cerebellum (sere-belum)

4. The brain stem, which consists of the medulla oblongata (med-dul ah ob long-gah tah), the pons, and the midbrain


The Cerebrum

The largest, most important, and most complicated part of thebrain is the cerebrum. The cerebrum controls motor activities,interprets sensations, and serves as the center of intellect,memory, language, and consciousness.

The Diencephalon

The diencephalon consists of two major structures: the hypothalamus and the thalamus. Although the hypothalamusis one of the smallest parts of the brain, it controls importantfunctions such as body temperature, sleep, appetite, emotions,and the pituitary glanda master gland that directly orindirectly controls growth, development, and everyday functions.The thalamus serves as a relay station for body sensationsand helps the body interpret the sensations as pleasurable or not pleasurable.

FIGURE 2Parts of the Brain


The Cerebellum

The cerebellum has three main functions:

1. It coordinates and smoothes voluntary movements suchas running, walking, writing, and talking.

2. It helps to maintain muscle tone and posture.

3. And, because it receives impulses from the inner ear, it helps maintain equilibrium or a sense of balance.

The Brain Stem

The brain stem has three parts:

1. The medulla oblongata

2. The pons

3. The midbrain

The medulla oblongata connects the spinal cord with the rest of the brain. It controls vital systems and structuressuch as the heart, respiration, and blood vessels (whichaffect blood pressure).

The pons connects the cerebrum and the cerebellum.

The midbrain, the shortest part of the brain stem, controls visualand auditory reflexes. For example, the constriction of yourpupils when you enter a bright room is due to the midbrain.

The Spinal Cord

You already know that your spinal column is what earns youthe distinction of being a vertebrate rather than a backbone-less jellyfish or other invertebrate. Inside the spinal columnlies the spinal cord, a slightly hollow cylinder of neural tissuewhich is attached to the brain stem.

As part of the central nervous system, the spinal cords mainfunctions are to relay information to the brain and controlmany reflex activities of the body.


THE ANATOMY AND PHYSIOLOGYOF THE PERIPHERAL NERVOUSSYSTEM

The peripheral nervous system consists of 12 pairs of cranialnerves and 31 pairs of spinal nerves. All of these nerves consistof fibers that may be sensory, motor, or a combination of both.

Sensory nerves are afferent (afer-ent) nerves. They receiveinformation from the sense organsthe ears, eyes, nose,tongue, and skinand send that information to the brain.Motor nerves are efferent (efer-ent) nerves. They receiveorders from the central nervous system and carry the ordersout. Mixed nerves contain both sensory and motor nerves.

Cranial Nerves

The 12 pairs of cranial nerves arise from the undersurface of the brain. Arranged in pairs identical in function andstructure, these nerves carry impulses between the brain and the head and the neck. The nerves are named for thearea or function they serve.


Spinal Nerves

Thirty-one pairs of spinal nerves originateon the spinal cord, and they can begrouped as follows:

8 cervical pairs

12 thoracic pairs

5 lumbar pairs

5 sacral pairs

1 coccygeal pair

Figure 3 illustrates the spinal cord and thespinal nerves.

The spinal nerves branch into the trunkand limbs of the body to form the many remaining and too-numerous-to-countperipheral nerves. The function of thespinal nerves is to conduct impulsessend informationbetween the spinal cord and the parts of thebody not supplied by the cranial nerves. Spinal nerves help youto experience sensations and to make movements possible.

FIGURE 3The Spinal Cord and the Spinal Nerves


PATHOLOGY OF THE NERVOUS SYSTEM

The various disorders of the nervous system are grouped inthe following manner:

1. Vascular disorders

2. Infectious disorders

3. Degenerative and movement disorders

4. Seizure disorders

5. Congenital disorders

6. Neoplastic disorders

Self-Check 1At the end of each section of Anatomy and Physiology, youll be asked to pause and check

your understanding of what youve just read by completing a Self-Check exercise.

Answering these questions will help you review what youve studied so far. Please complete

Self-Check 1 now.

1. List the structures of the central nervous system and the peripheral nervous system:

CNS PNS

__________________________ __________________________

__________________________ __________________________

2. Two types of protective coverings of the central nervous system are _______ and _______.

3. The chief function of the 12 pairs of cranial nerves is to _______.

4. The chief function of the spinal nerves is to _______.

Check your answers with those on page 95.


As you study the various disorders, youll find that eachgrouping covers a broad area of related possible problems.Different diseases or disorders may have similar symptoms indifferent combinations. If it seems confusing, youre right. Itis confusingeven doctors can be baffled by the variety andrange of symptoms that accompany disorders of the nervoussystem. Remember that the nervous system is the most com-plex system. As one nurse who specializes in neurology putit, For as much as we know about the nervous system,theres ten times as much that we dont knowyet. But thismuch is certainall the other systems depend upon thenervous system.

Vascular Disorders

A vascular disorder (vasku-lar) is a brain abnormality thatdevelops from defects in the blood vessels. Such defects causean inadequate amount of blood to reach the brain or actualbleeding in the brain tissue. This results in vascular disordersthat are generally called strokes. Strokes are life-threateningand require emergency care.

In cerebral thrombosis (sah-re brl throm-bo ss) an arterythat supplies blood to the brain narrows down, usually dueto atherosclerosis (ath er-o skle-ro ss), in which fatty depositsare formed and harden the arteries. It results in a thrombus(thrombus), or clot. The thrombus grows until it completelyblocks the artery.

A cerebral embolism (embo-lzm) is a blockage thats causedby a foreign object such as a bit of arterial wall or a smallblood clot from a roughened artery or diseased heart. It, too,obstructs the flow of blood to the brain.

A cerebral hemorrhage (sah-re brl hemor-j) is an artery thathas burst, allowing blood to seep into the surrounding braintissue. Eventually the seepage is stopped by a pressure buildupas the blood backs up outside the rupture and by the bloodsclotting mechanism. Aneurysms (anu-rzmz) are weakenedareas in the vascular walls, and these can rupture, too.


Transient ischemic (s-kemk) attack (TIA) is caused by briefbut critical periods of reduced blood flow to the brain. Whenenough blood doesnt reach the brain, the brain is deprived ofoxygen. The brain depends on oxygen and cant survive longwithout it. The symptoms of TIA resemble those of a stroke,but they last only a short amount of time. Often a TIA warnsof an impending stroke.

The symptoms of a cerebral thrombosis, embolism, hemorrhage,or TIA are an inability to speak, move, or feel, headache,numbness, blurred vision, confusion, and dizziness.

A subarachnoid hemorrhage occurs in the subarachnoid spacethat lies between the arachnoid and the pia mater. This spaceis filled with cerebrospinal fluid, the fluid that cushions thebrain and spinal cord. A subarachnoid hemorrhage occurswhen blood leaks into this space.

The symptoms of a subarachnoid hemorrhage are a suddenpainful headache, migraine, stiff neck, inability to endurebright light, faintness, confusion, drowsiness, nausea, andvomiting.

Other hemorrhages are usually caused by head injury. An extradural hemorrhage (ekstrah-du ral hemor-j), for example, is caused when an artery just inside the skull ruptures (usually through injury) and allows blood to flow between the dura mater and the skull. Another example is a subdural (sub-dural) hemorrhage, which occurs under thedura mater. Rather than the arteries, however, the large venoussinuses of the brain are responsible for the rupture.

The symptoms of extradural and subdural hemorrhages aredrowsiness, confusion, weakness, or numbness, persistent or recurrent headaches, and nausea. Symptoms worsen astime passes.

Infections

The brain and spinal cord are also protected in another way:they have no direct contact with the outside world. Therefore,infections arent as common as with other body systems.


When infections do occur, they usually gain entry in one ofthree ways: through the bloodstream, through the air spacesin the ears or sinuses, or through fractures caused by headinjuries. Infections of the nervous system can cause seriousdisease. Early diagnosis and treatment is important.

Meningitis (men n-jts) is an inflammation of the meninges,the membranous coverings of the brain and spinal cord. Theinfections usually result from an invasion of bacteria or viruses.

The symptoms of meningitis are fever, nausea, vomiting, stiffneck, inability to tolerate bright light, a deep red or purplishskin rash, drowsiness, and possible unconsciousness.

Encephalitis (en sef-ah-lts) is an inflammation of the brain and meninges thats caused by viral infection. Reyessyndrome is a form of encephalitis that affects the brain aswell as abdominal organs such as the liver. The cause isunknown, but the disease usually follows a viral illness.Some studies have been done that link Reyes syndrome withthe use of aspirin, but the results are still unclear. Reyessyndrome is usually found in children. The symptoms ofencephalitis are fever, headache, loss of energy and appetite,irritability, restlessness, and drowsiness.

Polio (po le-o) or poliomyelitis (po le-o-me-lts) is a viralinfection that attacks the muscle-controlling nerves. Poliowas once a crippling and life-threatening disease, but now,thanks to the development and availability of the Salk andSabin vaccines, occurrences of the disease are very rare.

The symptoms of polio are headaches, sore throat, fever, painin the neck and back muscles, and muscular weakness.

Shingles is an acute inflammation of nerve cells caused bythe chicken pox virus, herpes zoster (herpez zoster). Itsaccompanied by a rash of water blisters that are surroundedby a red area. It follows a nerve and forms a zone toward themidline on the trunk, but the lesions dont cross the midline.Shingles can develop from exposure to the disease during theinfectious stages or from exposure to chicken pox. Usuallyonly the pain and itching can be treated.

The symptoms of shingles are a severe burning pain in theaffected area and a rash of blisters.


Degenerative and Movement DisordersDegenerative disorders are diseases in which nerve cellsdegenerate or decline slowly, sometimes taking months oryears. Movement disorders can be similar to degenerative dis-orders because they can worsen over time, too. Movementdisorders are evident because they affect the muscles andtheir coordination.

Multiple sclerosis (MS) is a major disorder of the central nervous system. Its caused by an inflammation of the myelinsheath that covers the nerve pathways in the brain and spinalcord. The cause of this disease is unknown, but some believea virus is responsible. Although steroids and muscle relaxantsmay help, theres no effective treatment for MS.

The symptoms of MS are tingling, numbness, weakness that may affect one spot of the body, a loss of balance, poorcoordination, shaking tremors, difficulty in speaking clearly,and bladder dysfunction.

Amyotrophic lateral sclerosis (ah-m o-trofk later-al skle-ro ss), also called Lou Gehrigs disease, is a degenera-tive disease of the spinal cord and brain stem. This terminaldisease results from a steady loss of motor neurons. Itscause is unknown. The patient usually dies from pulmonaryfailure three to four years after contracting the disease.

The symptoms of amyotrophic lateral sclerosis are a weakeningof and disturbances in the muscles of the hands, forearms,and legs. Cranial and facial nervesespecially of the mouthand tongueare also afflicted. Speech becomes difficult orimpossible.

Parkinsons disease is a disease caused by gradual degenerationof certain nerve centers in the brain that control movement.The cause of the disease is unknown, but hereditary factorsmay be involved.

The symptoms of Parkinsons disease are mild hand tremors,a nodding head movement, and slow and difficult muscularmovements.

Palsy is a paralysis, meaning complete or partial loss ofmotor function, especially the limbs. Cerebral palsy results inpartial paralysis and a lack of motor coordination. Its caused


by a brain abnormality, usually due to damage to the cerebrumduring pregnancy or in the perinatal (per -na tal) period, theperiod shortly before and after birth. The damage may be dueto injury at or near the time of birth, an infection such asrubella (German measles), or an infection of the brain afterbirth. It usually results in mental and motor retardation.

Unilateral facial paralysis accompanies Bells palsy, a disorderof the facial nerve. The cause of Bells palsy is unknown, andcomplete recovery is possible.

The symptoms of palsy are tense muscles and exaggeratedreflexes; uncontrollable, constant, purposeless movementsand tremors of the hands and/or feet; or poor balance and astaggering gait.

Seizure Disorders

A seizure (se zhur) is generally known as a convulsion (kon-vulshun), an involuntary contraction or series of con-tractions by voluntary muscles. Any irritation of the nervescan lead to seizures. Such irritations include infectious diseases such as meningitis and encephalitis.

Epilepsy (ep-lep se) is a form of convulsion or seizure. Thereare many forms of epilepsy, but whatever the form is, theseizure is caused by a problem in communication betweenthe brains nerve cells. This breakdown in communicationresults in a temporary disturbance of the brains impulses.

Congenital Disorders

A congenital (kon-jen-tal) disorder is a disorder that occursduring fetal development. Although congenital disorders arenthereditary, they can be very serious. Remember that the cen-tral nervous system develops in the fetus during the first twomonths of pregnancy; consequently, congenital disorders ofthe central nervous system can be especially serious.

Spina bifida (spnah bf -da), as its name suggests, affectsthe spinal cord. Its a condition in which part of the bony spinethat helps protect the spinal cord fails to develop properly.


As a result, one or more vertebrae fail to fuse, leaving anopening in the vertebral canal. Usually spina bifida affectsthe lower spine, which may result in an inability to use theleg muscles or control bladder and bowel functions.

Hydrocephalus (h-dro-sefah-lus) literally means water orfluid on the brain or head. Its caused either by a defectivemembrane in a developing fetus or from cerebrospinal fluidthat has been blocked and builds up pressure in the cavitiesof the brain. The pressure causes the brain to swell. Becausethe bones in the skull are loosely connected, they spreadapart. Although the babys head may appear normal at birth,within months it grows larger than normal. In severe cases,the brain is permanently damaged.

Neoplastic Disorders

As youve already learned, a neoplasm is a new growth,which may be a benign or malignant tumor. Even benigntumors can be harmful to the brain because as they grow,they strangle vital nerve centers. Benign tumors can usuallybe removed successfully through surgery. Malignant cancerspose more of a risk because their extensive roots are difficultif not impossibleto completely remove. Furthermore, malig-nant brain tumors are often secondary cancers that havespread from other organs.

The symptoms of malignant tumors include frequentheadaches, nausea, vomiting, blurred or double vision, theloss of smell and/or memory, and a personality change.


COMBINING FORMS AND SUFFIXES RELATED

TO SYMPTOMS OF DISORDERS AND/OR DISEASES

OF THE NERVOUS SYSTEM

Combining Form Meaning Example

QUADR/I four quadriplegia (kwod r-ple je-ah) paralysis of all four extremities

SYNCP/O to cut off, syncope (snko-pe) temporary suspension of to cut short consciousness due to generalized cerebral ischemia

TAX/O order, coordination ataxia (ah-takse-ah) failure of muscular coordination

-ESTHESIA feeling, nervous paresthesia (par es-the ze-ah) sensations such asprickling, sensation burning, and tingling for no apparent reason

OTHER TERMS RELATED TO DISEASES/DISORDERS OF THE NERVOUS SYSTEM

coma (ko ma) abnormally deep unconsciousness with the absenceof voluntary response to stimuli

lethargy (leth ar-je) or torpor (torpor) condition of sluggishness; abnormal inactivity or alack or response to normal stimuli

syncope (snko-pe) fainting

tremor (tremor) involuntary shaking or trembling

ABBREVIATIONS RELATED TO THE PATHOLOGY OF THE NERVOUS SYSTEM

ANS autonomic nervous system

CAT scan computerized axial tomography

CT scan computerized tomography scan

CNS central nervous system

CP cerebral palsy

CVA cerebrovascular accident

EEG electroencephalogram

MS multiple sclerosis

PNS peripheral nervous system

TIA transient ischemic attack

FLASH INTO MEMORY

1


TESTS AND PROCEDURES OF THENERVOUS SYSTEM

This next section is designed to familiarize you with the basictests and procedures used to diagnose disorders and diseasesof the nervous system.

Youve already studied the basic disorders and diseases thatcan afflict the nervous system. Of course, youve heard thesaying, An ounce of prevention is worth a pound of cure.This is especially true of care for the nervous system. Becausethe nervous system is so complex and fragile, its importantthat its well cared for. The first step in preventative care isproper immunization.

Self-Check 2Identify the following disorders as vascular, infectious, degenerative and movement,

seizure, congenital, or neoplastic.

1. Palsy ________________________________________________________________

2. Spina bifida __________________________________________________________

3. Malignant brain tumor __________________________________________________

4. Hydrocephalus ________________________________________________________

5. Meningitis __________________________________________________________

6. Encephalitis __________________________________________________________

7. Multiple sclerosis ______________________________________________________

8. Epilepsy __________________________________________________



There are two ways to become immune to a disease. The firstway is called natural immunity. If you catch an infectious disease such as measles, your body produces antibodies(ant-bod ez) that attack and destroy the measles-causingorganisms. Your symptoms disappear, and you recover fromthe disease. If youre ever exposed to measles again, the anti-bodies will protect you from contracting the disease again.

The second way you become immune to a disease is calledartificial immunity, which can be either permanent or temporary immunity. Temporary immunity occurs when aphysician injects you with antibodies which guard againstdisease for a short period of time. Permanent immunity occurswhen youre given a vaccine, which is made from dead orharmless versions of the particular disease. A vaccine foolsyour body into developing antibodies to fight off the disease(which you never actually contract), and you become immuneto the particular disease. Vaccines are given either by injec-tion or by mouth. Vaccines are generally administered duringchildhood, but some vaccines (such as tetanus) need to beboostered periodically throughout adulthood.

Laboratory Tests

Cell counts, bacterial smears, and cultures of samples ofcerebrospinal fluid (CSF) are conducted when a disease of themeninges or the brain is suspected. Changes in the makeupof the CSF may indicate brain disease. The fluid is obtainedthrough a procedure called a lumbar puncture or spinal tap.


Radiology Tests and Clinical Procedures

A CT (computerized tomography) scan of the brain provides athree-dimensional view of the brain.

In an MRI (magnetic resonance imaging) of the brain, magneticwaves create an image of the brain.

Surgical Procedures

A craniotomy (kra ne-oto-me) is a surgical opening in the skull.

In cryosurgery (kro-surjer-e) tissue is exposed to extremecold. This technique is sometimes used to destroy parts ofthe brain.

A laminectomy (lam-nekto-me) relieves pressure on spinalnerves due to a herniated disk by removing part of the vertebra.

A lobotomy (lo-boto-me) severs the nerve fibers in the frontallobe of the brain. A prefrontal lobotomy is a procedure in whichthe connecting fibers between the prefrontal lobes of the brainand the thalamus are severed.

Neurolysis (nu-rol-ss) is the freeing of a nerve from an adhesion.

A neurotomy (nu-roto-me) is the surgical incision or the dissection of a nerve.

Schedule of Necessary Immunizations for Prevention

of Diseases Related to the Nervous System

DPT (Diphtheria, pertussis, tetanus) By injection or mouth at ages 2 months, 4

vaccine (also called DTP or DT&P) months, 6 months, 1518 months, and from

46 years of age

DT (Diphtheria and tetanus) booster By injection from 1416 years of age

(also called TD)

Poliomyelitis vaccine By injection or mouth at 2 months, 4 months,

618 months, and from 46 years of age

Measles, mumps, German measles By injection at 1215 months, and from 46

(rubella) vaccine (also called MMR) years of age or 1012 years of age


Pharmacology Related to the Nervous System

Analgesics (an al-je zks) inhibit the passage of pain impulses.Examples of analgesics are aspirin, codeine, and morphine.

Anticonvulsants (an t-kon-vulsants) suppress seizures.

Antidepressants (an t-de-pressants) raise the norepinephrineand/or serotonin levels in the CNS by constricting or narrow-ing the blood vessels.

Opiates (o pe-ts) are sedative narcotics that contain opium orits derivatives.

Psychotropic drugs (s ko-tropk) modify a patients mental activity and mental state. Theyre often used to treat schizophrenia. Examples of psychotropic drugs arestimulants, such as caffeine, amphetamines, cocaine; opiates,such as morphine, heroin, methadone; and hallucinogens,such as marijuana, LSD, and PCP.

Sedatives (sedah-tvz) and hypnotics calm nervousness, irritability, and excitement. They also induce sleep.

Tranquilizers (trankw-lzers) reduce mental tension andanxiety without interfering with normal mental activity.


Self-Check 31. Name and describe two types of immunity.

__________________________________________________________

__________________________________________________________

2. The letters DPT stand for _______, _______, and _______.

36: Add the proper suffix to the following tests and procedures.

Suffixes:

-ectomy -surgery -lysis

-gram -graphy -otomy

3. The record of brain-wave activityelectroencephalo________

4. Tissue is exposed to extreme coldcryo_______

5. The freeing of a nerve from adhesionneuro_______

6. A surgical opening in the skullcrani_______



Part 2: The Sensory System

INTRODUCTION

If someone were to ask you to name the sense organs, whatorgans would you name?

Its easy to think of the five sensessight, sound, smell,touch, and tasteand the organs that govern these senses.But if those were the only sense organs you named, youveoverlooked millions of other sense organs that the body has.Yes, thats rightmillions.

These sense organs are receptors, located throughout yourbody in the skin, internal organs, and muscles. Receptorsallow you to distinguish touch, pressure, temperature, andpain, and they provide you with information that enables youto sense even the most subtle changes in our environment.Have you ever sensed danger? Have you ever experienced aflash of intuition? Can you drive around the block withoutgetting lost? If so, thank your hard-working receptors.

Dont worry about memorizing the names of millions of receptors,though. This study unit focuses on the senses of taste, smell,equilibrium, sight, and hearing.

THE ANATOMY AND PHYSIOLOGYOF THE SENSE ORGANS

The senses are divided into two groups: special sense organsand general sense organs.

The special sense organs are the eye, the ear, the nose, andthe taste buds.

The general sense organs are the tactile receptors, the tem-perature receptors, the pain sensors, and the proprioceptors.

Of course, no sensory awareness would be possible withoutthe nervous system. Heres a brief review to remind you howthe nervous system works with the sensory organs. After thereceptors detect a stimulus (stmu-lus), something that spurs


them into activity, the stimulus is converted into an electricalsignal or nerve impulse. The signal then travels the nervepathways to the brain, where the sensation is actually per-ceived or interpreted. After the brain interprets the stimulus,it sends orders back along the nerve pathways to the organsand/or other muscles.

THE EYE

The eye provides us with a great deal of information about ourenvironment. A delicate organ, its protected by the skeletalbones of the face, which are cushioned by layers of fat. Eyelashesand eyelids protect the eye from foreign particles; tears alsokeep the eye moist and free of dust and foreign particles.

Parts of the Eye

The human eye is shaped with a bulge, the only part thatsvisible when we look at another person or in the mirror. Thisbulge is protected by the upper and lower eyelids. The rest ofthe eyeball lies hidden from view in the bony socket of theskull. Although eyes may appear large or small, all humaneyes are actually about the same size. Its the size of the lidopenings that makes eyes appear large or small. The portionthat you see is small compared to the whole eyeball.

Three layers of tissue form the eyeball:

1. The sclera (sklerah) and the cornea (korne-ah)

2. The choroid (ko roid) layer

3. The retina (ret-nah)

The rest of the eyeball is composed of the lens, the ciliary (sl e-er e) muscle, the iris (rs), and the inner cavities.

For vision to occur, several processes take place. First, the irismuscle determines how much light to allow to pass throughthe pupil. Second, the lens adjusts in order to determine thedistance of the object. This process is called accommodation,an automatic process that adjusts the curvature of the lens toenable the eye to focus on close objects. Third, both eyeballsmust be positioned so that theyre directed toward the object.


Accessories of the Eye

Eyebrows and eyelashes protect the surface of the eye by filtering out foreign particles.

Eyelids are composed mainly of muscle and skin. Eyelidsalso serve to protect the eye.

The lacrimal (lakr-mal) glands produce tears to bathe andlubricate the eye.

DISEASES OF THE EYE

Optical Defects of the Eye

Ametropia (am e-tro pe-ah) is an error of refraction. Ametropiais caused when light rays arent brought into proper focus onthe retina. It usually results from a defect in the lens, cornea,or the shape of the eyeball. If the eye is too long from front toback, the lens cant bring distant objects into focus on theretina. This lack of focus results in nearsightedness, or myopia(m-o pe-ah). If the distance between the front of the eye andthe back of the eye is too short, hyperopia (hper-o pe-ah) orhypermetropia (h per-me-tro pe-ah) (farsightedness) results.In many eyes the cornea is misshaped so that its surface isoval instead of spherical. This misshapen cornea results inan astigmatism (ah-stgmah-tzm), which causes light raysto spread out over a large area of the retina, rather thanbeing sharply focused.

Strabismus (strah-bzmus) is a condition in which the eyesturn from the normal position so that theyre not aimed inthe same direction and therefore cant work together. Theimages that are produced on the retinas are so dissimilarthat the brain cant blend them. Hence, a double imageresults. Strabismus may result from poor vision, poor ocularmuscle tone, or an oculomotor nerve lesion. Amblyopia (am ble-o pe-ah), lazy eye syndrome, is seen in childrenwho suffer from suppressed vision in one eye. As a result,they use only one eye.


Organic Defects of the Eye

Conjunctivitis (kon-junkt-vts), more commonly known aspinkeye, is the irritation and inflammation of the membranethat lines the inner surface of the eyelids. This condition canbe caused from exposure to smoke, dust, or similar irritants.

A sty is a common disorder of the eyelid. The condition iscaused by an infection of the small glands of the eyelash.Bacteria grows and results in the reddening and swelling ofthe entire eyelid. The condition can be contagious.

More serious diseases are cataracts (katah-rakts), glaucoma(glaw-ko mah), and retinitis pigmentosa (ret-ntspgmen-to sah). A cataract is a cloudy or opaque discolora-tion in the lens of the eye caused by a buildup of protein. As the protein builds, vision gradually decreases. Cataractsurgery, removal of the lens, is the only effective treatment.

If the watery fluid in front of the lens fails to drain properly,pressure builds in the eye, resulting in glaucoma. Glaucomais treated by releasing the excessive fluid from the eye.Medications that allow the pupils to constrict are effective in some cases; in others, surgery may be necessary.

Retinitis pigmentosa is a chronic, progressive eye disease. Itresults in degeneration of the retina and the atrophy of theoptic nerve, leading ultimately to blindness. Theres no cure.

Retinal detachment occurs when the two layers of the retinaseparate from each other. It usually results from trauma to theeyeball, head injuries, scarring from infection, or shrinkage ofthe jellylike substance behind the lens.


CLINICAL PROCEDURESRELATED TO THE EYE

In a retinoscopy (ret -nos ko-pe), a beam of light thatreflects from the retina is used to determine whether the eye is nearsighted or farsighted.

A visual field examination measures the area within whichobjects may be seen when the eye is fixed, looking ahead.

In a tonometry (to-nome-tre), a tonometer measures theintraocular pressure of the eye; this procedure is used todetect glaucoma.

A visual acuity test examines the acuteness or sharpness ofvision. The Snellen eye chart may be used.

THE EAR

Usually when you think of ear, you think of the thin, skin-covered cartilage that collects sound. But theres much moreto the ear than the flap thats attached to the side of yourhead. A large part of the earand its most important partlies hidden from view, deep inside the temporal lobe.

The ear is divided into three parts:

1. The external or outer ear

2. The middle ear or tympanic cavity (tm-pank kav -te)

3. The inner ear or labyrinth (lab-rnth)

The External Ear

Sound is collected by the skin-covered cartilage that formsthe auricle (awre-kl), the outermost part of the external ear.Sound waves travel through the auditory canal (awd-to rekah-nal) that curves into the temporal bone and ends at thetympanic membrane, more commonly known as the eardrum.The eardrum separates the external and middle ears.


The Middle Ear

After the sound waves strike the eardrum, the middle earintensifies and transmits the sound. Whereas the externalear conducts sound through air, the middle ear conductssound through bone. Three tiny bones, called ossicles (os-klz), lie within the middle ear.

The Inner Ear

The inner ear is the most complicated part of the ear because,in addition to its role in your hearing, the inner ear also helpsyou to maintain your sense of equilibrium and balance.

DISEASES OF THE EAR

Diseases of the Outer Ear

An acoustic neuroma (ah-koostk nu-ro mah) is a benigntumor of the auditory canal that grows progressively larger. It arises from the acoustic nerve (the eighth cranial nerve) in the brain. It causes tinnitus (ringing in the ears), vertigo(dizziness), and decreased hearing. Small tumors may beremoved by microsurgery.

Diseases of the Middle Ear

Serous otitis media (serus o-t ts mede-ah) is an inflammation of the middle ear, also known as tympanitis(tm pah-n ts). The treatment for this disease includes aspiration of the fluid and the placement of tubes in theeardrum to allow ventilation of the middle ear.

Suppurative otitis media (sup ur-ah-tv o-t ts me de-ah) is an inflammation of the middle ear caused by bacterialinfection and pus formation. Antibiotics usually work well in fighting the disease.


Diseases of the Inner Ear

Menieres disease (men e-arz) is a chronic disease of the innerear characterized by elevated endolymph pressure within thecochlea. The symptoms include dizziness, progressive unilat-eral nerve deafness, and a ringing sound in the ears. The causeof the increased pressure is unknown; sometimes surgery isnecessary to drain the accumulated fluid from the inner ear.

Vertigo (ver t-go) is a sense of whirling, dizziness, and loss of balance.

The Loss of Hearing

Deafness, the complete or partial loss of the ability to hear, mayrange from the inability to hear sounds of a certain pitch orintensity to a complete loss of hearing. Deafness can be dividedinto two types: nerve deafness and conduction deafness(kon-dukshun). Nerve deafness is caused by damage to thecochlear or auditory nerve. Conduction deafness results froman inability of the middle ear ossicles and membranes totransmit sound waves into the cochlea.

Presbycusis (pres be-ku ss) is a progressive hearing lossthat occurs as a part of the aging process.

Tinnitus (tn-n tus) is a ringing sound in the ears.

CLINICAL PROCEDURESRELATED TO THE EAR

A finger-nose test checks for coordinated movement of theextremities. The patient closes the eyes, extends an arm toone side, and slowly tries to touch the end of the nose withthe index finger.

A falling test observes the patient for marked swaying orfalling, which may indicate vestibular and cerebellar dysfunc-tion. During the test the patient is instructed to stand, witheyes open, on one foot, stand heel to toe, and then to walkforward. The patient then repeats the test with the eyes closed.


An audiometry (aw de-om e-tre) determines the patientsability to hear sound frequencies at different intensities. Anaudiometer (aw de-om e-ter), a device for testing hearingand for measuring bone and air conduction, is used. Anaudiogram (aw de-o-gram) is a graph of the test results.

THE SENSE OF SMELL

Have you ever sniffed a particular scent and suddenly foundyourself miles away, lost in memories? The pathways thatscents travel and the part of the brain that analyzes the scentsalso work closely with memory and emotion. Thats why thesense of smell can evoke powerful feelings and memories.

In addition to being a vital structure for respiration, the nosealso functions as a sense organ. A highly specialized collec-tion of nervous tissue, the olfactory bulb (ol-fak to-re bulb),or olfactory epithelium (ol-fak to-re ep -the le-um), enablesyour nose to smell. The smells detected by this nervous tis-sue are sent along the olfactory nerve (the first cranial nerve)to the olfactory center in the brain. There, the brain analyzesthem and sends that information along.

Olfactory nerves are never replaced; once theyre damaged,the sense of smell is impaired forever. They also tire quickly,which explains why a pungent odor seems to dull after itsbeen sensed for a while.

THE SENSE OF TASTE

About 10,000 taste buds bring sour, salty, bitter, and sweetsensations to our palate every day. But the taste buds dontwork alone: they work with the sense of smell for your diningpleasure.

The tongue is a complex muscle that aids your digestive sys-tem greatly. It helps you speak, moves food around as youchew it, and molds the food into a ball for swallowing. Itssurface is covered with hairlike projections called papillae(pah-pl e); clusters of taste buds surround the papillae.


For a taste to be stimulated, the food must be dissolved insaliva. Sweet and salty tastes are sensed mainly at the tip of the tongue. Sour taste is sensed at the sides of the tongue,and bitter taste is sensed at the back of the tongue. The tastebuds dont just help you to enjoy your food, however. Theyalso alert you to food that tastes bad or is spoiled. In thisway, the tongue also performs a protective function.

Tastes are detected by the gustatory cells (gus tah-to re), specialized cells in the taste buds. The information is thenconverted to impulses, and three cranial nervesthe facial,glossopharyngeal, and vagus nervestransmit the impulsesto the brain.

THE GENERAL SENSES

The general sense organs enable you to experience touch,pressure, vibration, pain, changes in temperature, and muscle stretch. The receptors for these senses are spreadthroughout the integumentary system of your body andwithin some of its internal organs.

Tactile receptors (tak tl re-septorz) bring you informationabout pressure, touch, and vibration. Theyre mostly locatedthroughout your skin, but are most numerous in areas suchas the fingertips and lips (Figure 4).

Temperature receptors enable you to sense changes in thetemperature. Although theyre found throughout the body,theyre concentrated in the lips, mouth, and anus.

Pain receptors are located throughout the skin and certaininternal organs. Some organs, however, are poorly suppliedwith pain receptors, making it difficult for you to determinewhere it actually hurts. Its especially difficult if the pain isreferred to another area. An example of pain being referred toanother area is a headache: sometimes its actually the bloodvessels or meninges beneath the skull that hurt, not the actualsite of the pain. Endorphins (en-dor fnz) are chemicalsreleased by the central nervous system. When endorphins are released, the amount of pain you feel is decreased.


Proprioceptors (pro pre-o -septorz ) enable you to sense theposition of various body parts (without looking!). They alsoenable you to sense whether the body parts are moving anddetermine in what direction theyre moving. This sense ofposition is called proprioception (pro pre-o-sep shun) or kinesthesia (kn es-the ze-ah). The receptors for this senseof position are located within muscles, joints, and tendons.

FIGURE 4Tactile Receptors in a Section of Skin


Self-Check 41. Name the four special sense organs.

__________________________________________________________

2. The part of the eye that determines how much light passes through the pupil is the _______.

3. The _______ tests the sharpness of vision.

4. Name three parts of the ear.

__________________________________________________________

5. _______ is a sense of dizziness and loss of balance.

6. The olfactory bulb enables your nose to _______.

7. How many taste buds do you have?

__________________________________________________________

8. The sense of position is called _______.



NOTES


Part 3: The Circulatory System

INTRODUCTION

Nowhere in the human organism is the word system moreappropriate than when used in the phrase circulatory system(serku-la tore), the bodys network for distributing substances.The circulatory system is the highway system for trans-porting oxygen, nutrients, hormones, immune agents, andother necessary substances to cells and then carting awaythe garbage. Sounds simple, right? But this is one group oforgans that are so interrelated and perform so many vitalfunctions so smoothly that, like a professional athletic teamor symphony orchestra, they only make it look simple!

The circulatory system circulates blood and lymph. Thus thereare two major subsystems within the circulatory system, andeach of those has subsubsystems:

The cardiovascular systemblood, blood vessels, and heart

The lymphatic or immune systemlymph, lymph vessels, and lymphatic tissues

THE ANATOMY AND PHYSIOLOGYOF THE CIRCULATORY SYSTEM

The Blood System

Blood has many functions in sustaining life, from transportingoxygen and nutrients to body tissues, to transporting carbondioxide from those tissue to the lungs, to filtering metabolicwastes through the kidneys. Blood delivers hormones to targetorgans, keeps cellular fluids balanced, fights infections, andhelps regulate body temperature. All of this adds up to oneimportant word: homeostasis. More than any other system,blood maintains the overall environment necessary for sus-taining the balance of life. And blood can do all of thisbecause of its unique composition.


Plasma

Approximately 55 percent of the total blood volume is plasma (plazmah), a clear, yellowish fluid made up of 92percent water and 7 percent proteins. Dissolved sugar, salts,hormones, gases, wastes, and other substances make uponly 1 percent of plasma. When the clotting factor fibrinogenis removed, the fluid is called serum.

Blood Cells

There are three types of blood cells or formed elementssuspended within the plasma and comprising the remaining45 percent of blood volume. The first type are red blood cells,which carry oxygen. The second type are white blood cells,which are colorless cells that fight infection. Finally, there areplatelets (plat lets), the clotting cells. Their job is to adhere tothe edges of injured blood vessel walls to stop the bleeding, aprocess called blood clotting, or coagulation (ko-ag u-la -shun).When you cut your finger, platelets and other substances willclot the site to prevent loss of blood and begin the healingprocess.

The Vascular System

There are three types of blood vessels: arteries, veins, andcapillaries.

Arteries (arter-ez) are the large vessels leading away fromthe heart. They have strong, elastic walls to respond to theheavy force of blood pressure. The most important arteries toknow are the pulmonary (pulmo-nere) arteries to the lungs;and the aorta (a-ortah), the great artery, whose branchesreach to all body systems. The smaller stems off arteries arecalled arterioles (ar-tere-olz), which can help regulate bloodpressure by expanding or contracting. Since the heart isalways hard at work pumping blood through arteries, any cut or severing of arterial walls can lead to excessive andeven fatal bleeding. Thats why arteries are found deep within the bodys flesh.


Veins (vanz) are the large (though not as large as arteries)vessels leading into the heart. Two very important veins arethe superior vena cava (soo-pere-or venah kavah) comingfrom the upper body and the inferior vena cava (n-fere-orvenah kavah) from the lower body. Since the blood hasslowed down to a crawl by the time it gets to the veins, theydont need the thickness nor the elasticity of arteries. Indeed,if a vein is cut, it will often collapse. Since theres less risk ofbleeding to death through veins, theyre closer to the bodyssurface, and its veins that make bluish lines (like roads on amap) under your skin. Blood samples are taken from veins.

The milking action of muscles around the veins keeps bloodmoving along the veins and back to the heart. Unlike arteries,many veins have valves that prevent backflow of blood.

There are, however, a few arteries that you should memorizebecause theyre common checkpoints in physical exams.

Brachial (brake-al) arteryblood pressure is usually taken atthis point just above the elbow.

Carotid (kah-rotd) arterythis is the neck artery that para-medics and ER staff check for signs of life in unconsciouspatients.

Radial (rade-al) arterythe pulse is usually taken here, onthe thumb side of the wrist.


The Heart

The heart is located centrally in the body. It leans a little tothe left between the lungs.

The heart is a hollow muscle thats always exercising, alwayskeeping blood on the move. If it stops pumping, then lifeceases within minutes. Although the heart is roughly the sizeof a fist and weighs less than a pound, its hardy enough topump 80 million gallons worth of blood during an averagelifespan. Actually, the heart is a double pump. Its right sidetakes care of pulmonary circulation, pumping stale bloodthrough the lungs to get rid of carbon dioxide and pick upfresh oxygen. This oxygenated blood comes back throughthe left side of the heart for systemic circulation, that is,pumping to the various body systems.

Self-Check 5Fill in the term that fits each description.

1. Lymph, lymph vessels, and lymphatic tissues

__________________________________________________________

2. Vessels leading away from the heart

__________________________________________________________

3. Vessels leading to the heart

__________________________________________________________

4. Major blood vessels branching off to the body systems

__________________________________________________________



Have you ever wondered exactly why the heart can pump,pump, pump without ever getting tired and needing a break?Cardiac muscle isnt like the other muscles of the body. Itdoesnt depend on the nervous system to send the impulsesto contract and relax.

The heartbeat has two phases. Systole (ssto-le) is the periodof contraction, when blood is pumped. Diastole (d-asto-le) isa period of relaxation, in which the ventricles fill with blood.What we call blood pressure is actually a measurement ofpressure placed on arterial walls during systole and diastole.In the average blood pressure of 120/80, the 120 representsa systolic pressure of 120 millimeters of mercury; the 80,diastolic pressure of 80 millimeters of mercury.

The average pulse in adults is anywhere between 60 and 80heartbeats per minute, but this may double during vigorousexercise, and the cardiac output may quadruple.

The Lymphatic System

The lymphatic system is a network of capillaries, vessels, ducts,nodes, and organs that take a detour from the cardiovascularthruway to transport lost proteins and fluids back into thebloodstream. Even more important, the lymphatic system is a major highway for the immune system, which defends thebody against foreign substances and disease. The lymphaticsystem also absorbs fats from the small intestine and deliversthem into the bloodstream.

In strategic locations along the lymph vessels there are clustersof lymphatic tissue called lymph nodes. Lymph nodes not onlyproduce lymphocytes that travel throughout the body to fightdisease, but they also filter lymph and trap foreign substances.When youve had a sinus infection or a sore throat, did youget a sore swollen gland in your neck? Thats a lymph nodethat has engulfed bacteria and dead cells to prevent theinfection from spreading. Physicians often palpitate lymphnodes to check for accumulation of debris as evidence ofinfection. Thus, transcriptionists should know that there arenodes in the cervical (neck), axillary (armpit), mediastinal(chest), inguinal (groin), and popliteal (knee) regions.


PATHOLOGY OF THE CIRCULATORY SYSTEM

Depending on what the cardiovascular problem is, the patientmay have tachycardia (tak e-kar de-ah), an abornmally rapidheart rate; or bradycardia (brade-kar de-ah), an abnormallyslow heart rate. Dyspnea (dspne-ah) (difficult breathing),especially shortness of breath, is also a common symptom ofdiseases of the circulatory system because when the blood-stream isnt circulating enough oxygen, the bodys tissues willsend messages to the lungs to pick up the breathing pace. Ifthe oxygen depletion to the brain is extreme, then syncope(snko-pe) (fainting) may occur. Cyanosis (sah-noss), abluish tint to the skin and mucous membranes, may alsodevelop because of oxygen depletion.

Pathology of the Blood

Anemia

Anemia (ah-neme-ah), the most common of blood conditions,isnt really a disease but a symptom of any disease causinga deficiency in oxygen supply to the bodys tissues. Poor diet,blood loss, congenital defects in RBCs, and diseases of thebone marrow are some of the common underlying causes ofanemia. All types of anemia cause fatigue and lack of energy.

Hemophilia

Hemophilia (hemo-fle-ah), is an inherited disorder of bloodclotting factors, affecting males primarily but passed on byfemales. Hemophiliacs experience prolonged bleeding evenwith the most minor cuts, and they bleed internally as well.Bleeding into the joints causes intense pain and permanentcrippling. Blood transfusions may be necessary as lifesavingmeasures during bleeding episodes. Patients need to avoidsituations that might lead to injury, such as contact sports.Patients also need to undergo transfusions to increase thelevel of clotting factors in the patients blood.


Leukemia

Leukemia (loo-keme-ah) is cancer of the blood-forming tissues,popularly thought of as blood cancer of the white blood cellsbecause the leukocyte count is elevated by well over 20 timesits normal amount. Meanwhile, red blood cell and plateletcounts are diminished. Thus the patient is left anemic, sus-ceptible to infection, and with a tendency to bleed (duringtoothbrushing or defecation, for instance). Other possiblesymptoms include fever, pain in the joints and bones,headache, sore throat, fatigue, dyspnea, and swelling of thelymph tissues.

Treatment of leukemia is a combination of chemotherapy andmedication. When the patient goes into remission, a period inwhich the signs of disease are absent, then a bone marrowtransplant may be performed. If leukemia cells return, this iscalled a relapse.

Pathology of the Blood Vessels

Hypertension

High blood pressure on the arteries, hypertension (h per-tenshun), nicknamed the silent killer, is the culprit behind many deaths due to damage or failure of vitalorgansmost often the heart, brain, and kidney. Studiesestimate that one in six Americans has high blood pressure.

What causes this silent killer? Its known that high bloodpressure and hardening of the arteries usually go together.You probably know about the links between cardiovasculardisease and lifestyle: smoking, a diet high in cholesterol,stress, hyperactive personality, and lack of exercise can allcontribute to hypertension. Nevertheless, the ranks of peoplewith high blood pressure include calm vegetarians who jogevery day and dont smoke.

Chronic hypertension leads to hypertensive heart disease, inwhich the left ventricle enlarges in its effort to pump bloodthrough narrow blood vessels. The heart literally works itselfto death.


Arteriosclerosis

To some degree, arteriosclerosis (ar-tere-o-skle-ross) is alsoa natural part of aging. Its a frequent cause of death. The innerlining of the arteries becomes thick and loses elasticity. Themost common form is atherosclerosis (ath er-oskle-ross),in which plaques (plaks) (fatty deposits) narrow the opening ofthe blood vessels. Plaques are composed mostly of cholesterol,a major reason why physicians encourage patients to limitthe amount of cholesterol in their diets.

Plaques causing coronary artery disease may occlude the ves-sels supplying the heart, leading to myocardial infarction, orheart attack. Indeed, blockage of virtually any major vein or artery can lead the heart to overwork and ultimately to fail.When blood flow to the brain is diminished, the patient maysuffer a cerebral vascular accident (CVA), also known as astroke. When the arteries of the lower extremities becomeblocked from atherosclerosis, the condition is called occlusivevascular disease.

Angina

Another common condition attributable to atherosclerosis isangina pectoris (an-jnah pekto-rs), acute pain in the chestbecause of decreased blood supply to the heart. What decreasesthe supply is usually stenosis (ste-noss), or narrowing, ofthe aorta, coronary arteries, or pulmonary arteries. While thepain of angina pectoris affects the heart, the pathology is inthe blood vessels.

Attacks of angina generally accompany emotional stress orphysical activity, both of which give the heart extra work todo. The demand for oxygen becomes more than the narrowedblood vessels can supply. Symptoms include a tight, heavy,suffocating feeling that may spread from the chest to theneck, throat, left arm, and sometimes the stomach and back.This pain lasts only 10 or 15 minuteseven less, with a doseof nitroglycerine (n-tro-glser-n) or nitrates (ntrats) todilate the coronary arteries. Patients with angina are vulnerableto myocardial infarction, but they can control the conditionby identifying and avoiding the situations that cause attacks.


Aneurysms

Another common result of atherosclerosis is the dilation of a wall of an artery, vein, or the heart into a saclike swellingcalled an aneurysm (anu-rzm). Most patients dont feel anysymptoms unless the aneurysm is large enough to put pressureon nearby tissues.

The chief danger of an aneurysm is that it will grow large,rupture, and hemorrhage. A ruptured aortic aneurysm is par-ticularly dangerous, since the internal bleeding will be severeand lead to shock. A ruptured cerebral aneurysm resembles astroke in its effect on the brain. Treatment of aneurysms dependson the size and location. Small aneurysms in harmless loca-tions will be simply watched. Large aneurysms anywhere,or any aneurysm in a dangerous place such as the aorta oriliac arteries, will usually be surgically repaired to prevent therisk of rupture.

Thrombosis

Blood clots are usually good for the body. They form overinjuries to promote healing, to say nothing of preventing theperson from bleeding to death. Blood clots also form overinjuries to the insides of blood vessels, or in places where theflow of blood is impeded for some reason, such as damage toa valve, atherosclerosis, or even prolonged physical inactivity.A thrombus is an intravenous clot that obstructs the flow ofblood. The lack of blood supply to an organ causes tissuedeath, or necrosis (ne-kross). The dead tissue is called aninfarct and may develop gangrene (gangren).

Thrombus is the name of the clot. Thrombosis (throm-boss) isthe name of the disease. Coronary thrombosis is a clot insidea coronary artery, and a major cause of myocardial infarction.The most frequent site of thrombosis, however, is the veins ofthe legs and pelvis, since blood flows so slowly there.

If a thrombus breaks away from the blood vessel wall andtravels through the blood stream, the clot is called an embolus (embo-lus), and sooner or later it will get stuck in atight spot, an obstruction called an embolism (embo-lzm).Depending on where it lodges, an embolism can cause evenmore damage than if it stayed a thrombus in the leg.


Symptoms of an obstructed artery include severe pain, fainting,nausea, vomiting, and shock. Shock is the acute failure of thecirculatory system to supply the body with nutrients and oxygen.To restore circulation, anticoagulant drugs or surgicalremoval of the clot will be necessary.

Phlebitis

Its common for inflammation of a vein to occur, especially inthe lower limbs. Phlebitis often occurs as a secondary condi-tion of other disorders. For instance, it may accompany poorcirculation in general, result from obesity (people who areexcessively overweight tend not to get enough exercise tokeep the venous blood moving), or develop after bedrest frominjury or surgery.

If embolism is a likely threat, surgery may be performed toremove the thrombus. People prone to develop thrombophlebitisare often encouraged to wear elastic stockings as a preventativemeasure.

Raynauds Disease

For some people, cold temperatures or emotional stress canbring on acute episodes of ischemia and numbness of the fingers, toes, ears, or nose. Raynauds (ra-noz) disease isrelieved by heat.

Heart Diseases

Myocardial Infarction (MI)

Heart disease and vascular disease are often interrelated. Forinstance, hardening of the arteries, or arteriosclerosis, can leadto heart disease and ultimately to heart failure. The formationof clots on blood vessel walls, a condition called thrombosis,can occur in the coronary artery and cause ischemia, the lack of blood flow to an organ. If the organs blood supply isoccluded (blocked), the result will be an infarct, or death oftissue. In the case of heart tissue, such death is called amyocardial infarction (mo-karde-al n-farkshun). This is a true heart attack.


Coronary artery disease is the foremost cause of MI, butshock, hemorrhage anywhere in the body, and even severephysical exertion can also cause it because they all decreasethe flow of fresh blood through the coronary arteries.

Occlusion of a small artery may cause mild damage. Occlusionof a large artery may cause death. In survivors of heart attack,the damaged muscle will form scar tissue, like any wound,but it will never pump again. In many cases the remaininghealthy heart will grow stronger, and the patient can prolonglife by following a careful regimen of healthful diet, bloodpressure medication, rest, exercise, and stress management.

Just about everbody knows the symptoms of heart attack, yetmany victims dont know theyre having one. The most obvi-ous sign is crushing pain in the chest, but pain referredto the arms, throat, and back can be tricky. The pain cancreep up for hours. Signs of shock will be presentpallor andperspiration, especially. Often, nausea and vomiting will leadthe victim to mistake the symptoms for a flu or virus. Thevictim puts off going for the emergency care that might preventor at least lessen the severity of the MI. The final symptom iscardiac arrest, the stoppage of heart action. The patient willlose consciousness, and at this point immediate cardiopul-monary resuscitation (karde-o-pul mo-ner-ere-sus -ta shun)(CPR) with emergency cardiac care (ECC) is the only chance forsurvival. Early thrombolytic (throm bo-lt k) therapy withclot-dissolving drugs such as streptokinase (strepto-knas)and tissue plasminogen activator (t-PA) can prevent the severedamage to the myocardium that usually follows a heartattack. Depending on the point of occlusion and the patientsoverall condition, it may be possible to restore the flow ofblood to the heart by coronary bypass surgery to implant one of the patients own veins in place of the occluded vessel;or by percutaneous transluminal coronary angioplasty(per ku-tane-us trans-loom-nal koro-na-re anje-o-plaste)(PCTA) using a balloon-tip catheter to compress plaques againstblood vessel walls.


Congestive Heart Failure (CHF)

Congestion is the abnormal collection of blood in a body part.Congestive heart failure (CHF) is a failure of the heart to pumpblood efficiently, usually because of water and sodium retention.CHF is often confused with heart attack, but this sort offailure isnt the same as an MI. It may, however, precede orfollow a true heart attack. It also may be associated withother cardiovascular problems such as high blood pressure,aortic stenosis (see the section on valvular diseases), andcoronary artery disease.

Arrhythmias

Any abnormal rhythm of the heartbeat is called arrhythmia(ah-rthme-ah). When the arrhythmia becomes noticeable tothe person because of its force, rapidity, or irregularity, thenthe sensation is called palpitation (pal p-tashun)but pal-pitations can also be caused by nervousness and excitement.

Flutter (fluter) is an abnormally rapid but regular quiver of230380 contractions per minute in the atria or ventricles.

Fibrillation (f-br-lashun) is an abnormally rapid and irregularquiver of 350 contractions or more per minute. Fibrillation isoften the cause of cardiac arrest, and to prevent this outcomethe physician will attempt to restore normal heart rhythm byapplying an electric shock to the heart wall with a devicecalled a defibrillator (de-fbr lator). Drugs, most commonlydigitalis (dj tals), may be given to regulate fibrillation.

Congenital Heart Disease

As you know, any congenital disease is present at the time ofbirth. Congenital heart disease exists in less than 1 out ofevery 100 newborns, owing to faulty development of the heartand/or blood vessels.

Symptoms such as cyanosis (causing a blue baby) and dys-pnea make it obvious that the newborn has a heart defect.But in milder cases, symptoms of heart disease may not beevident until the child grows older. Many defects are so minorthat no treatment is necessary other than keeping an eye on it.


Major defects can often be corrected with surgery. During anyheart surgery, the patients general circulation will be maintainedby a heart-lung machine, a process called extracorporeal circulation (eks trah-kor-pore-al ser ku-lashun).

Lymphatic Pathology

Lymphomas

There are several neoplasms of lymphoid tissues, thought tobe caused by a virus. Lymphomas (lm-fomahz) are classfiedaccording to what type of cell becomes malignant and howthe disease progresses. This form of cancer generally weakensthe bodys immune system. Radiation usually controls a local-ized case, but if the cancer has spread through the lymphaticsystem, then chemotherapy will be necessary.

Acquired Immune Deficiency Syndrome (AIDS)

Acquired immunodeficiency syndrome, also known as AIDS, wasrecognized by the Center for Disease Control (CDC) in 1981.Since then, it has become clear that this incurable disease isa worldwide health problem. By 1997, the number of peopleof both sexes and all lifestyles living with HIV/AIDS is 30.6million.

As every aware person should know by now, the humanimmunodeficiency virus (HIV) that causes AIDS is transmittedthrough exchanging body fluids with an infected person, pri-marily through sexual activity or intravenous injection. Itsimportant to note that a person can be infected with HIV foryears before developing AIDS. During this time, the infectedperson can unknowingly transmit the virus to others.

Why is AIDS so deadly, and a cure so hard to find? By killingimportant lymphocytes, HIV suppresses the immune systemso that it can no longer fight disease.

During an early stage of AIDS called AIDS-related complex(ARC), the patient has mild symptoms such as weight loss,fever, diarrhea, anorexia, fatique, and so on. The ability tofend off disease remains quite good. Once full-blown AIDSstrikes, rendering the immune system powerless, the patient


becomes subject to opportunistic infections such as Kaposissarcoma (kahpo shez sar-komah), pneumocystis cariniipneumonia (noo mo-ssts kah-rne- nu-mone-ah),and lymphoma. Though theres no cure for AIDS, thedrugs azidothymidine (az -do-thm-den) (AZT) and dideoxyinosine (dd e-oks n-o-zen) (ddI) do prolong healthy life by inhibiting the reproduction of HIV withininfected cells.

Lymphedema

Lymphedema is a condition where protein-rich fluid accumu-lates, causing chronic swelling, due to an inpaired transportcapacity of lymphatic fluids. Its usually caused by the removalof regional lymph nodes due to surgery or radiation.

Procedures of the Circulatory SystemIt may be that the circulatory system is subject to the mosttesting of any system in the body. After all, thats where theblood isand blood tests are used in diagnosing pathologiesof all sorts. The importance of a healthy heart in stayingalive, combined with the prevalence of heart disease as acause of death, have led to extensive research in methods ofpreventing, detecting, and treating cardiovascular disorders.

A way of determining the hearts health is by measuring itselectrical activity in electrocardiography (e-lek tro-kar de-ograh-fe) (ECG or EKG). The pattern that the electro-cardiograph machine records on paper indicates the heartsrhythms, as well as other actions. Patients with suspectedcardiac arrhythmias or unexplained angina may wear aminiature electrocardiograph called a Holter monitor to traceheart activity over a 24-hour period.

Youve probably heard of cardiac catheterization (kath e-ter--zashun). If catheterization of the urinary bladder is used to drain urine, does that mean cardiaccatheterization is used to drain blood? No! The catheter isguided through veins and into the heart to measure the flowof blood, its pressure, and other important activities. Acatheter may also be used to inject dye for x-ray procedures.


Youve probably also heard of the stress test used to monitorthe progress of heart patients. While the patient is jogging ona treadmill or doing some other form of controlled exercise, anumber of tests will be performedECG, blood pressure,breathing rate, and so on.

Self-Check 6Match the term on the left with its description on the right. Indicate your choices in the

spaces provided.

______ 1. Myocardial infarction

______ 2. Flutter

______ 3. Cyanosis

______ 4. Congenital heart disease

______ 5. Fibrillation

______ 6. Congestive heart failure

79: Indicate whether the following statements are True or False.

______ 7. Lymphoma is leukemia of the lymph.

______ 8. Kaposis sarcoma is an opportunistic infection common in AIDS patients.

______ 9. An early stage of AIDS is AZT.


a. Blue tint from oxygen deprivation

b. Congestion of the heart and lungs

c. Heart defect present at birth

d. Irregular arrhythmia

e. Heart attack

f. Regular arrhythmia


NOTES


Part 4: The RespiratorySystem

THE ANATOMY AND PHYSIOLOGYOF THE RESPIRATORY SYSTEM

Introduction

All living things need oxygen, or they would die. Your respira-tory system enables you to exchange oxygen and carbondioxide between the atmosphere and the cells of your body.Two forms of respiration make this possible: external andinternal respiration. External respiration (lung breathing)involves the inhalation of oxygen into the air sacs of thelungs. From there it passes into the tiny capillaries whichsurround the air sacs. Internal respiration(tissue breathing) provides the exchange ofgases within all the organs of the body.

As an adult you take about 12 to 15 breathsper minute when awake and 6 to 8 whenasleep. However, during stressful moments,you may take many more breaths perminute.

Respiratory organs include the nose, pharynx,larynx, trachea, bronchi, and lungs (Figure 5).These organs resemble an upside-down treein your body. And you can imagine that theyfunction in a similar way, too. The leaves ofa tree take in carbon dioxide that nourishesthe entire tree, roots and all. Your respira-tory system takes in oxygen that nourishesyour entire body, cells and all. The treeexchanges carbon dioxide for oxygen, andyou exchange oxygen for carbon dioxide. FIGURE 5The Respiratory System


The NoseThe nose has two main jobs. First, it provides our bodies withwarm, filtered, and moistened oxygen. Second, it holds theolfactory nerve that enables us to detect and distinguish odors.Air enters the body through the external nares (narez), ornostrils. The septum extends from the nares to the nasal partof the pharynx, or nasopharynx (nazo-farnks).

The external nares are lined with mucous membranes andshort, coarse hairscilia (sle-ah)that filter out foreignparticles such as dust. The sinuses are cavities in the bonesof the skull that open into the nasal cavity.

The PharynxYour pharynx (farnks), (Figure 6) or throat,is a multipurpose tube leading from the backof the nose and mouth, down to the trachea(trake-ah) (windpipe) and to the esophagus(e-sofah-gus). It allows air to reach yourlungs and food to reach your stomach.

The adenoids (ade-nodz) are lymphatic tissues that assist the bodys defensesagainst infection. Theyre located within thepharynx. Tonsils serve to keep infections

away from the lower tract and are located within the pharynx.The palatine tonsils are a prime area of infection. When theinfections become recurrent, the tonsils are often removed.

The LarynxWhen you speak, you use your voice box or larynx (larnks),which is located beneath the pharynx. The larynx is made ofseveral pieces of cartilage, the largest of which is the thyroidcartilage, more commonly known as the Adams apple. Airthat passes over the vocal chords produces sound. The sizeand tightness of the vocal cords determine the sound of yourvoice. The space between the vocal chords is the glottis (glots).And the epiglottis (ep-glots), a leaf-shaped flap on top ofthe larynx, is responsible for sealing off the airway to thelungs when you swallow food or water.

FIGURE 6The Pharynx


The Trachea

Beneath the larynx is the trachea (trake-ah),a smooth muscle tube thats ribbed with C-shaped cartilage rings. The trachea con-nects the larynx and bronchi. Its locatedanterior (in front of) to the esophagus.

The Bronchi

Further down, the trachea separates intotwo branches, which are called the bronchi(Figure 7). These branches lead to the rightand left lungs. Each primary bronchusdivides again and again into tinier second-ary bronchi, air passageways that resembletiny offshoots of a branch. Oxygen is carriedto all parts of the body.

The Lungs

Although the body consists of several pairedstructures that are identical, the lungs arentexactly alike. The right lung is divided intothree lobes, and the left lung is divided intotwo lobes. Consequently, the right lung islarger than the left lung.

FIGURE 7The Pharynx, Trachea, Bronchi, and Lungs


The Mucous Glands, Mucous Membranes, and Mucus

The mucous glands, also called respiratory mucosa, are glandsthat line most of the air-distribution tubes in the respiratorysystem. Over these glands lies the mucous membrane. Themucous glands are responsible for the production of mucus,which coats the mucous membrane.

Mucus is one of the most important air purification mechanismsthat our bodies have. The mucous glands work to removealmost every form of contaminant before the air can reachthe lungs.

How the Respiratory System Works

You already know the path that the air follows to reach thelungs. To understand the mechanics of breathing, you need toknow more about the muscles that make respiration possible.

The chest cavity is an airtight box. The top and sides of thebox are formed by the ribs and muscles. The bottom of thebox is a dome-shaped muscular partition called a diaphragm(dah-fram).

If you can imagine an accordion, you can imagine the move-mentthe swelling and the contractingthat the chest cavitydoes as it expands with each inhalation and contracts witheach exhalation (Figure 8).

When you breath in or inspire (n-spr), the rib muscles (theinspiratory muscles) pull the ribs upward and the diaphragmpushes downward. As the size of the chest cavity increases,the chest rises.

When you breathe out or expire (ek-spr), the rib muscles(now called the expiratory muscles) contract and the dia-phragm relaxes, moving gently upward. This is what makesthe chest fall.


The blood that flows from the right ventricle of the heartenters the pulmonary artery, and from there it enters thelungs. In the lungs, the blood becomes oxygen rich. The oxygen-rich blood then continues on its journey throughoutthe body, bringing oxygen to all the cells. The exchange ofoxygen between the blood and tissue capillaries and bodycells is called internal respiration.

FIGURE 8The Mechanics of Breathing


Self-Check 712: Name two types of respiration and describe or define each in a sentence.

1. ________________________________________________________

2. ________________________________________________________

38: In order, list the path that air takes to reach your lungs.

3. ________________________________________________________

4. ________________________________________________________

5. ________________________________________________________

6. ________________________________________________________

7. ________________________________________________________

8. ________________________________________________________

9. Another name for the windpipe is _______.

10. Another name for the voice box is _______.

11. Tiny hairs that line the nose are called _______.

12. The _______ seals off the airway to the lungs when food and water are swallowed.

Match the term on the left with its definition or function on the right. Indicate your choices

in the spaces provided.

______ 13. Bronchi

______ 14. Diaphragm

______ 15. External respiration

______ 16. Internal respiration

______ 17. Mucous membrane

______ 18. Trachea


a. Dome-shaped muscle partition

b. Exchange of carbon dioxide between body andenvironment

c. Membrane that lines the air tubes

d. A smooth muscle thats lined with C-shaped cartilage tubes

e. Alveoli are found at the ends of these

f. Exchange of oxygen between blood and tissues


DISEASES OF THE RESPIRATORY SYSTEM

Pulmonary ventilationbreathingsupplies your body withthe oxygen it needs and gets rid of the carbon dioxide it doesnt need. You breathe about 20,000 times per day, inhaling as much as 35 pounds of air. Thats much morethan the amount of food and drink you consume each day.

Although your body is also equipped to filter out harmfulparticles, it cant guard against everything. Consequently,with each inhaled breath, you also breathe in viruses, bacteria,allergens, and other irritants that hover about in your environ-ment, waiting to sneak into your respiratory tract. If youre ill,you also release bacteria and viruses into the atmosphereeach time you exhale. These, in turn, look for another respi-ratory tract to invade.

There are two main categories of diseases of the respira-tory system. Diseases of the nose and throat (pharynx andlarynx), are known as upper respiratory diseases. Diseases of the trachea, bronchi, and lungs are known as lower respiratory diseases.

Diseases of the Nose and Throat

The Common Cold

Although we refer to it as the common cold, a cold is actuallya group of minor illnesses, all of which cause an acuteinflammation of the mucous membrane that lines the upperrespiratory tract. A cold can be caused by any one of almost200 different viruses! Thats why theres no immunity to acold. Another strain of virus is always ready to attack.

Since everyone gets colds, youre probably aware of the symptoms: runny nose, sneezing, watery eyes, sore throat,hoarseness, and coughing. Nasal discharge turns from wateryto a thick, greenish-yellow. You may get a headache andslight fever. You might suffer from shivering and the chills.


Although many people believe that you can catch a cold fromwet feet or from not wearing a jacket in cold weather, thissimply isnt true. Only a virus can cause a cold. Colds arehighly contagious and seem to spread through direct contactwith other people who have colds.

If you treat a cold, it will last a week; if you dont treat a cold,it will last seven days. Yes, its true. Although some medica-tions offer relief for some symptoms, the medications simplycant make the cold vanish any faster. It has to run its course,which makes the best medicine old-fashioned chicken soupand your favorite bathrobe and slippers.

Because bacterial infection often develops with the cold, theinfection may spread to the paranasal sinuses or down thetrachea. Consequently, some symptoms might require a doctors care. These symptoms include earache, pain in theface or forehead, a fever above 102 degrees, a combination ofpersistent hoarseness or sore throat, shortness of breath andwheezing, and a dry, painful cough.

Allergic Rhinitis (Hay Fever)

If youre allergic to airborne allergens (aler-jenz), substancessuch as pollen, dust mites, feathers, or animal dander thatcause hypersensitivity, you probably suffer from allergic rhinitis (ah-lerjk r-nts) (hay fever) or asthma because youhave hypersensitive antigens (ant-jenz) in your body. If youhave hay fever, your eyes, nose, and throat react to the aller-gens. If you have asthma, your chest and lungs react.

Sinusitis

Sinusitis (snu-sts) is an inflammation of the mucousmembranes of the sinuses. Its cau