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A set of two interactive CD- ROMs that cover each body system and demonstrate clinical ACKNOWLEDGMENTS concepts provigil 200 mg for sale, histology provigil 200 mg without prescription, and physiology with animated three- Preparing a new edition of a text is a formidable task that in- dimensional and other images. And in the case of this text, even family members were Paolini, San Diego State University. My sincere gratitude is extended to faculty and stu- full-color, high-resolution light micrograph images and 35 scan- dents who have used previous editions of this text and have ning electron micrograph images of selected tissue sections typi- taken the time to suggest ways to improve it. Each image has labels thinking of others who will be using the text in the future, and at that can be clicked on or off, has full explanatory legends, offers the same time, ensuring a future for the text. Ronald Galli, colleagues at Weber State University, who were especially supportive of my efforts in preparing this edition. Feedback from conscientious students is espe- logical processes that are narrated and animated in vibrant cially useful and appreciated. Several physicians contributed clinical input to this edi- Life Science Animations (LSA) videotape series contains 53 tion. Prince animations on five VHS videocassettes: Chemistry, the Cell, and Karianne N. Prince for their contributions of additional and Energetics; Cell Division, Heredity, Genetics, Reproduc- Clinical Practicums and the accompanying radiographic images. A father’s request to three of his sons resulted in Another available videotape is Physiological Concepts of Life additional clinical input. Van De Graaff for their generous suggestions and genuine interest in Atlas to Human Anatomy by Dennis Strete, McLennan what their dad does. This atlas Crawley has continued to be supportive of my writing endeavors. This atlas in the previous editions and a number of new ones for this edi- is a guide to the structure and function of human skeletal tion. The illustrations help students locate muscles and Watts, Department of Radiology at the Utah Valley Regional understand their actions. Medical Center, provided many of the radiographic images used Laboratory Atlas of Anatomy and Physiology, third edition, in the previous editions of this text and some new ones for this by Eder et al. Thanks are also extended to Don Kincaid and Rebecca skeletal anatomy, human muscular anatomy, dissections, and Gray of Ohio State University, who dissected and photographed reference tables. Sponsoring Editors Marty Lange and Kristine Tibbetts and as it was being developed for the sixth edition. These profession- Developmental Editor Kristine Queck were superb to work with. Both of these people spent countless hours attending the myriad details that a technical text such as this involves. Naples University of Manitoba University of South Carolina–Spartanburg Northern Illinois University Frank Baker Allan Forsman Daniel R. Olson Golden West College East Tennessee State University Northern Illinois University Leann Blem Carl D. Frailey Scott Pedersen Virginia Commonwealth University Johnson County Community College South Dakota State University Carolyn W. Peterson Bossier Parish Community College Citrus College Indiana University of Pennsylvania Russ Cagle Douglas J. Reichard Willamette University University of Kentucky Chandler Medical Maple Woods Community College Paul V. Center Alexander Sandra Eastern Kentucky University Melanie Gouzoules University of Iowa Brian Curry University of North Carolina–Greensboro David J. Hirsch Morehead State University Shirley Dillaman East Los Angeles College Stephen P. Dooly Oklahoma State University Leeann Sticker Ball State University Glenn E. Brent Thomas Biola University Dennis Landin University of South Carolina–Spartanburg Charles A. Miller Southeastern Oklahoma State University Eastern Illinois University xvi Van De Graaff: Human Front Matter A Visual Guide © The McGraw−Hill Anatomy, Sixth Edition Companies, 2001 Visual Guide Chapter Outline A page-referenced preview of major topics is included on the Body Organization and opening page of each chapter, allowing you to see at a glance what Anatomical Nomenclature the upcoming chapter covers. As you read the chapter, watch for the background information needed to Clinical Case Study solve the case study, then check your answer against the solution A young woman was hit by a car while crossing a street. Upon arrival at the scene, paramedicsfound the patient to be a bit dazed but reasonably lucid, complaining of pain in her abdomen and the left side of her chest.

Nerve impulses from the inspiratory portion travel through the phrenic and intercostal nerves and stimulate the diaphragm and intercostal muscles discount provigil 100mg otc. Impulses from the expiratory Aortic bodies portion stimulate the muscles of expiration order provigil 200mg amex. These two portions act Ascending reciprocally; that is, when one is stimulated, the other is inhibited. The apneustic center promotes inspiration and the pneumotaxic center inhibits the activity of Heart inspiratory neurons. The brain stem respiratory centers produce rhythmic breathing even in the absence of other neural input. This intrin- sic respiratory pattern, however, is modified by input from higher brain centers and by input from receptors sensitive to the chemi- cal composition of the blood. Two groups of chemoreceptors respond to changes in blood Knowledge Check chemistry. These are the central chemoreceptors in the medulla oblongata and the peripheral chemoreceptors. State where in the brain the three respiratory areas are lo- chemoreceptors include the aortic bodies, located in the aortic cated. Which of these three areas is responsible for auto- arch, and the carotid bodies, located at the junctions of the in- nomic rhythmic breathing? Describe the locations of the peripheral chemoreceptors chemoreceptors control breathing indirectly via sensory neurons and identify the two paired cranial nerves that carry sen- to the medulla oblongata. The aortic bodies send sensory infor- sory impulses from these sites to the respiratory centers mation to the medulla oblongata in the vagus nerves; the carotid within the brain stem. Respiratory System © The McGraw−Hill Anatomy, Sixth Edition Body Companies, 2001 Developmental Exposition ing the seventh week, and a single large oronasal cavity forms. The Respiratory System Shortly thereafter, tissue plates of mesoderm begin to grow hori- zontally across the cavity. At approximately the same time, a ver- tical plate develops inferiorly from the roof of the nasal cavity. EXPLANATION These plates have completed their formation by 3 months of de- The development of the respiratory system is initiated early in velopment. The vertical plate forms the nasal septum, and the embryonic development and involves both ectoderm and en- horizontal plates form the hard palate. Although all of the structures of the respiratory sys- tem develop simultaneously, we will consider the upper and A cleft palate forms when the horizontal plates fail to meet in the midline. This condition can be corrected surgically lower systems separately because of the different germ layers (see fig. In humans, pouching, from the ventral surface of endoderm along the cephalization is apparent early in development. This diverticulum, which tial events is the formation of the nasal cavity at 3 1/2 to 4 forms during the fourth week of development, is referred to as weeks of embryonic life. The placode invaginates to portion bifurcates (splits) into a right and left principal form the olfactory pit, which extends posteriorly to connect bronchus. The foregut, derived of endoderm, later devel- The buds continue to elongate and split until the entire ops into the pharynx. As the terminal portion forms air sacs, called pul- nasal cavity, and for a short time there is a thin oronasal mem- monary alveoli, at about 8 weeks of development, the sup- brane separating the two cavities. The complete structure of the lungs, however, is not fully developed until about 26 weeks of fetal development. Premature infants born prior to this time therefore require special artificial respiratory equip- cephalization: Gk. Respiratory System © The McGraw−Hill Anatomy, Sixth Edition Body Companies, 2001 EXHIBIT I The development of the upper respiratory system. Respiratory System © The McGraw−Hill Anatomy, Sixth Edition Body Companies, 2001 Right principal bronchus Left principal bronchus EXHIBIT II The development of the lower respiratory tract. A cleft palate may be hereditary or a complication of some The respiratory system is particularly vulnerable to infectious dis- disease (e.

The temporal lobe is located is the major area responsible for receptive under the frontal and parietal lobes and function discount provigil 100mg visa, or the ability to integrate visual is primarily responsible for the interpreta- and auditory information in order to tion of and distinction between auditory understand a communication received purchase provigil 200mg on line. The occipital lobe is located at the area located in front of the temporal lobe back or posterior portion of each hemi- and in the frontal cortex is called Broca’s sphere. It is the primary area for reception area, which contributes to expressive and interpretation of visual stimuli. The thala- as expressing thoughts in a coordinated mus acts as a relay station that sorts, inter- way so that others may comprehend it. Language function is located in the left Below the thalamus is the hypothalamus, hemisphere of the cerebrum in most indi- which coordinates neural and endocrine viduals, whether they are right- or left- activities. An area located over the temporal internal environment and behaviors that 30 CHAPTER 2 CONDITIONS OF THE NERVOUS SYSTEM: PART I are important to survival, such as eating, ried by four major arteries, two carotid drinking, and reproduction. The ver- hypothalamus is the pituitary gland, an tebral arteries join to form the basilar endocrine gland that will be discussed in artery. A band of gray THE BRAIN matter called the hippocampus is involved in learning and long-term memory, help- Traumatic and Atraumatic ing to determine where important and rel- Brain Damage evant aspects of facts will be stored. The brain, like any other tissue, needs Beneath the occipital lobe of the cere- oxygen in order to function. The damage are dependent on: cerebellum also regulates and coordinates fine movements of the extremities, which • the cause of the damage have been initiated by the frontal lobe. Atraumatic (nontraumatic) brain dam- is the primary center of involuntary func- age caused by interference with oxy- tions. Control of vital organ functions gen reaching the brain (such as with such as regulation of heartbeat or respira- choking, carbon monoxide poison- tion occurs in the brain stem. Areas in the ing, or infection) or problems with- brain stem also regulate the diameter of in the brain itself (such as stroke, or blood vessels, consequently helping to structural problems within the brain control blood pressure. Reflex actions, or blood vessels in the brain) such as coughing and swallowing, are con- 2. The brain stem by an outside force that impacts the also contains scattered groups of cells, head hard enough to cause damage called the reticular formation, that are to the brain involved in the initiation and mainte- nance of wakefulness and alertness. Both atraumatic (nontraumatic) and trau- The brain requires both oxygen and matic brain damage are considered acquired nourishment in the form of glucose to brain injuries because they occur after birth function and survive. Oxygen and glucose and are not the result of genetic disorder, are transported to the brain by blood car- birth trauma, or degenerative disease. Conditions Affecting the Brain 31 Atraumatic Brain Damage bral thrombosis. Formation of the thrombus blocks blood flow to an Atraumatic brain damage, as just area of the brain. Because brain tissue explained, refers to conditions in which the needs the oxygen contained in blood brain has sustained damage due to condi- to survive, tissue that cannot obtain tions other than traumatic injury. This tissue death is called an or interference with blood and oxygen infarct. When a part pends on how large an area of the of the brain receives no oxygen (anoxia) brain has been deprived of blood sup- or too little oxygen (hypoxia), the tissue ply from the clot. Again, when the clot brain that then balloons out and can rup- occludes blood flow to a part of the ture), infections or inflammation of the brain, surrounding brain tissue dies. A third cause of stroke is hemorrhage, tions that deprive the brain of oxygen, which occurs because of rupture of a such as strangulation, near drowning, or blood vessel. When blood vessels are weakened because of dis- Stroke (Cerebral Vascular Accident) ease, such as with arteriosclerosis, or because of congenital weakness as Stroke, also known as cerebral vascular with an aneurysm, increased pressure accident, is a sudden alteration in brain may cause the blood vessel to burst. Stroke is usually the of oxygen, but also because the culmination of progressive disease that escaped blood compresses brain tis- has occurred over the course of many sue against the skull, causing further years. There are three as the result of stroke depends on: main causes of stroke: • the side of the brain affected 1. The most common cause is blocking • the specific area of the brain that has of a cerebral artery by a clot (throm- been damaged bus) that has formed inside the • the amount of damage that has artery, a condition referred to as cere- occurred 32 CHAPTER 2 CONDITIONS OF THE NERVOUS SYSTEM: PART I Often after stroke, in addition to the ini- tions. The organism recover, and function in these areas may also gains access to the cerebrospinal flu- be restored. Individuals with meningitis are usu- tions until months after the stroke as ally acutely ill, initially with fever and flu- occurred.

As thin myofilaments penetrate the I I A band from opposite sides 200mg provigil, they begin to meet in the mid- dle and interfere with each other (1 generic provigil 100 mg free shipping. At the A A A extreme, further shortening is limited by the thick filaments of the A band being forced against the structure of the Z lines (1. The relationship between overlap and force at short Moderate overlap lengths is more complex than that at longer lengths, since more factors are involved. It has also been shown that at I I very short lengths, the effectiveness of some of the steps in A A A the excitation-contraction coupling process is reduced. These include reduced calcium binding to troponin and some loss of action potential conduction in the T tubule system. Some of the consequences for the muscle as a whole are apparent when the mechanical behavior of mus- Most overlap cle is examined in more detail (see Chapter 9). The overall shortening is the sum of Events of the Crossbridge Cycle the shortening of the individual sarcomeres. Drive Muscle Contraction The process of contraction involves a cyclic interaction be- tween the thick and thin filaments. The steps that comprise amount of force that can be produced, since a shorter the crossbridge cycle are attachment of thick-filament length of thin filaments interdigitates with A band thick fil- crossbridges to sites along the thin filaments, production of aments and fewer crossbridges can be attached. Thus, over a mechanical movement, crossbridge detachment from the this region of lengths, force is directly proportional to the thin filaments, and subsequent reattachment of the cross- degree of overlap. At lengths near the normal resting bridges at different sites along the thin filaments (Fig. Most of our knowledge of this process comes from studies on skeletal muscle, but the same basic steps are followed in all muscle types. Initially, the crossbridges extend at right angles from each thick filament, but they rapidly undergo a 1. An ATP molecule bound to each crossbridge supplies the energy for this step. The myosin head to which the ATP is bound is called “charged myosin” (M*ADP*Pi in step 1). When charged myosin interacts with actin, the association is represented as A*M*ADP*Pi (step 2). The force a muscle can produce depends sociated with the final hydrolysis of the bound ATP and re- on the amount of overlap between the thick and thin filaments lease of the hydrolysis products (step 3), an inorganic phos- because this determines how many crossbridges can interact ef- phate ion (P ) and ADP. An impor- tant series of these steps, called excitation-contraction coupling, takes place deep within a muscle fiber. This is the Hydrolysis subject of the remainder of this chapter; the very early Product events (communication between nerve and muscle) and the A M*ADP release and very late events (actual mechanical activity) are discussed Detachment power in Chapter 9. The SR controls the internal concentration of these ions, and changes in the internal calcium ion concentration have The events of the crossbridge cycle in profound effects on the actions of the contractile proteins FIGURE 8. Undesired contraction is prevented by a spe- new ATP molecule binds to the myosin head and is ⑦ subse- quently hydrolyzed. These cyclic reactions can continue as long cific inhibition of the interaction between actin and as the ATP supply remains and activation (via Ca2 ) is main- myosin. The long tropomyosin molecules, lying in the grooves of the en- twined actin filaments, interfere with the myosin binding tion pulls the actin filaments past the myosin filaments, a sites on the actin molecules. Following this tions increase, the ions bind to the Tn-C subunit associated movement (which results in a relative filament displace- with each tropomyosin molecule. Through the action of ment of around 10 nm), the actin-myosin binding is still Tn-I and Tn-T, calcium binding causes the tropomyosin strong and the crossbridge cannot detach; at this point in molecule to change its position slightly, uncovering the the cycle, it is termed a rigor crossbridge (A*M, step 5). The myosin detachment to occur, a new molecule of ATP must bind to (already “charged” with ATP) is allowed to interact with the myosin head (M*ATP, step 6) and undergo partial hy- actin, and the events of the crossbridge cycle take place un- drolysis to M*ADP*Pi (step 7). Once this new ATP binds, the newly recharged myosin head, momentarily not attached to the actin fila- The Switching Action of Calcium. An effective switching ment (step 1), can begin the cycle of attachment, rota- function requires the transition between the “off” and “on” tion, and detachment again. This can go on as long as the states to be rapid and to respond to relatively small changes muscle is activated, a sufficient supply of ATP is avail- in the controlling element.