F. Quadir. Southwestern Assemblies of God University.
The muscles function either to move the toes or to support the arches of the foot through their contraction desyrel 100 mg free shipping anxiety scale 0-10. Because of their complexity buy desyrel 100mg cheap anxiety symptoms sleep, the muscles of the foot will be presented only in il- lustrations (see figs. List all the muscles that either originate from or insert on the scapula. On the basis of function, categorize the muscles of the upper extremity as flexors, extensors, abductors, adduc- tors, or rotators. Which muscles of the lower extremity span two joints, and therefore have two different actions? CLINICAL CONSIDERATIONS Compared to the other systems of the body, the muscular system is extremely durable. If properly conditioned, the muscles of the body can adequately serve a person for a lifetime. Muscles are ca- pable of doing incredible amounts of work; through exercise, they can become even stronger. The flexor digitorum longus Evaluation of Muscle Condition works over several joints, flexing the joints in four of the digits and assisting in plantar flexing the ankle joint and inverting The clinical symptoms of muscle diseases include weakness, loss the foot. The most obvious diagnos- The tibialis posterior muscle is located deep to the soleus tic procedure is a clinical examination of the patient. Its distal tendon passes be- this, it may be necessary to test muscle function using elec- hind the medial malleolus and inserts on the plantar surfaces of tromyography (EMG) to measure conduction rates and motor the navicular, cuneiform, and cuboid bones, and the second, unit activity within a muscle. A biopsy is perhaps the rior plantar flexes the ankle joint, inverts the foot, and lends sup- most definitive diagnostic tool. Muscular System © The McGraw−Hill Anatomy, Sixth Edition Companies, 2001 286 Unit 4 Support and Movement TABLE 9. Plantaris Lateral supracondylar ridge of Calcaneus Plantar flexes foot at ankle Tibial n. Obviously, overuse or disease will cause a change der may be either inborn or acquired. The immediate effect of overexertion on mus- A condition called rigor mortis (rigidity of death) affects cle tissue is the accumulation of lactic acid, which results in fa- skeletal muscle tissue several hours after death, as depletion of tigue and soreness. Excessive contraction of a muscle can also ATP within the fibers causes stiffness of the joints. This is similar damage the fibers or associated connective tissue, resulting in a to physiological contracture, in which muscles become incapable of strained muscle. A cramp within a muscle is an involuntary, painful, pro- When skeletal muscles are not contracted, either because longed contraction. Cramps can occur while muscles are in use the motor nerve supply is blocked or because the limb is immobi- or at rest. They may result from general dehydration, deficiencies of is resumed, as after a healed fracture, but tissue death is in- calcium or oxygen, or from excessive stimulation of the motor evitable if the nerves cannot be stimulated. Muscular System © The McGraw−Hill Anatomy, Sixth Edition Companies, 2001 Chapter 9 Muscular System 287 FIGURE 9. The fibers in healthy muscle tissue increase in size, or hy- column, where there are extensive aponeuroses. There are sev- myofibrils, accompanied by a strengthening of the associated eral kinds of muscular dystrophy, none of whose etiology is com- connective tissue. The most frequent type affects children and is sex-linked to the male child. As muscular dystrophy progresses, the muscle fibers atrophy and are replaced by adipose tissue. Most Diseases of Muscles children who have muscular dystrophy die before the age of 20. Pain and tenderness frequently occur in the extensor muscles of the lumbar region of the spinal lumbago: L. Muscular System © The McGraw−Hill Anatomy, Sixth Edition Companies, 2001 288 Unit 4 Support and Movement FIGURE 9.
Of clinical consideration is the fact that certain chemicals such as lipid-soluble toxins and pesticides can easily enter the body through the skin cheap desyrel 100 mg otc anxiety quiz. Communication Humans are highly social animals desyrel 100mg for sale anxiety girl meme, and the integument plays Synthesis an important role in communication. Various emotions, such The integumentary system synthesizes melanin and keratin, which as anger or embarrassment, may be reflected in changes of remain in the skin synthesis of vitamin D, which is used elsewhere skin color. The contraction of specific facial muscles pro- in the body and begins in the skin with activation of a precursor duces facial expressions that convey an array of emotions, in- molecule by UV light. The molecule is modified in the liver and cluding love, surprise, happiness, sadness, and despair. Only small amounts of UV light are necessary for vita- frequently elicit subconscious responses from others who de- min D synthesis, but these amounts are very important to a grow- tect them. Active vitamin D enters the blood and helps regulate the metabolism of calcium and phosphorus, which are important Knowledge Check in the development of strong and healthy bones. List five modifications of the integument that are struc- turally or functionally protective. Explain how the integument functions to regulate body flu- Sensory Reception ids and temperature. Integumentary System © The McGraw−Hill Anatomy, Sixth Edition Companies, 2001 Chapter 5 Integumentary System 115 EPIDERMAL DERIVATIVES Hair, nails, and integumentary glands form from the epidermal layer, and are therefore of ectodermal derivation. Hair and nails are structural features of the integument and have a limited func- tional role. By contrast, integumentary glands are extremely im- portant in body defense and maintenance of homeostasis. Objective 6 Describe the structure of hair and list the three principal types. Objective 8 Compare and contrast the structure and function of the three principal kinds of integumentary glands. Humans are relatively hairless, with only the scalp, face, pubis, and axillae being densely haired. Men and women have about the same density of hair on their bodies, but hair is generally more obvious on men (fig. Certain structures and regions of the body are hairless, such as the palms, soles, lips, nip- ples, penis, and parts of the female genitalia. It may be a genetic expres- sion, as in certain ethnic groups, or occur as the result of a metabolic disorder, usually endocrine. Hirsutism occurs in some women as they experience hormonal changes during menopause. Various treat- ments for hirsutism include hormonal injections and electrolysis to permanently destroy selected hair follicles. The eyelashes and the hair in the nostrils protect against airborne particles. Some secondary functions The life span of a hair varies from 3 to 4 months for an eye- of hair are to distinguish individuals and to serve as a sexual lash to 3 to 4 years for a scalp hair. The shaft is the visible, but dead, portion of sults when hair is lost and not replaced. This condition may be the hair projecting above the surface of the skin. The bulb is the disease-related, but it is generally inherited and most frequently enlarged base of the root within the hair follicle. As the treatment is effective in reversing genetic baldness; however, cells divide, they are pushed away from the nutrient supply to- flaps or plugs of skin containing healthy follicles from hairy parts ward the surface, and cellular death and keratinization occur. Integumentary System © The McGraw−Hill Anatomy, Sixth Edition Companies, 2001 116 Unit 4 Support and Movement (a) (b) FIGURE 5. A cuticle covers the cortex and forms the toughened outer of hair is determined by the cross-sectional shape: straight hair is layer of the hair.
The vitreous humor (or vitreous body) best 100mg desyrel anxiety or heart problem, a clear gelatinous substance desyrel 100mg without a prescription anxiety krizz kaliko, fills the large cavity between the rear of the lens and the front sur- face of the retina. The innermost layer of the eyeball is the retina, where the optical image is formed. This tissue contains the pho- toreceptor cells, called rods and cones, and a complex mul- tilayered network of nerve fibers and cells that function in the early stages of image processing. The rear of the retina is supplied with blood from the choroid, while the front is supplied by the central artery and vein that enter the eye- ball with the optic nerve, the fiber bundle that connects the retina with structures in the brain. The vascular supply to the front of the retina, which ramifies and spreads over the retinal surface, is visible through the lens and affords a direct view of the microcirculation; this window is useful for diagnostic purposes, even for conditions not directly re- lated to ocular function. At the optical center of the retina, where the image falls when one is looking straight ahead (i. During fixation macula is the fovea centralis, a depressed region about 0. With the lens flattened, parallel rays from a distant object are Slightly off to the nasal side of the retina is the optic disc, brought to a sharp focus. B, Lens curvature increases with accom- where the optic nerve leaves the retina. CHAPTER 4 Sensory Physiology 73 in the form of external lenses (reading glasses), is required The iris, which has both sympathetic and parasympa- for distinct near vision. They can be capable of a 30-fold change in area and in the amount of corrected with external lenses (eyeglasses or contact light admitted to the eye. Farsightedness or hyperopia is caused by an eyeball flex control, and bright light entering just one eye will that is physically too short to focus on distant objects. In effect, the converging power of the eye is too great; close Eye Movements. The extraocular muscles move the vision is clear, but the eye cannot focus on distant objects. These six muscles, which originate on the bone of the A negative (diverging) lens corrects this defect. If the cur- orbit (the eye socket) and insert on the sclera, are arranged vature of the cornea is not symmetric, astigmatism results. They are under visually Objects with different orientations in the field of view will compensated feedback control and produce several types have different focal positions. Vertical lines may appear of movement: sharp, while horizontal structures are blurred. This condi- • Continuous activation of a small number of motor units tion is corrected with the use of a cylindrical lens, which produces a small tremor at a rate of 30 to 80 cycles per has different radii of curvature at the proper orientations second. Especially in older adults, there may be a progressive and large, slow movements, used in following moving increase in its opacity, to the extent that vision is obscured. This condition, called a cataract, is treated by surgical re- Organized movements of the eyes include: moval of the defective lens. An artificial lens may be im- • Fixation, the training of the eyes on a stationary object planted in its place, or eyeglasses may be used to replace • Tracking movements, used to follow the course of a the refractive power of the lens. The peak spectral sensitivity ward to fix on near objects for the red-sensitive pigment is 560 nm; for the green-sen- • Nystagmus, a series of slow and saccadic movements sitive pigment, it is about 530 nm; and for the blue-sensi- (part of a vestibular reflex) that serves to keep the retinal tive pigment, it is about 420 nm. At wavelengths away from the optimum, the receives a slightly different image of the same object. Be- property, binocular vision, along with information about cause of the interplay between light intensity and wave- the different positions of the two eyes, allows stereoscopic length, a retina with only one class of cones would not be vision and its associated depth perception, abilities that are able to detect colors unambiguously. Many ab- of the three pigments in each cone removes this uncer- normalities of eye movement are types of strabismus tainty. Colorblind individuals, who have a genetic lack of (“squinting”), in which the two eyes do not work together one or more of the pigments or lack an associated trans- properly. Other defects include diplopia (double vision), duction mechanism, cannot distinguish between the af- when the convergence mechanisms are impaired, and am- blyopia, when one eye assumes improper dominance over the other. Failure to correct this latter condition can lead to loss of visual function in the subordinate eye.
PTSD is an anxiety dis- distress and impairment in social generic 100 mg desyrel visa anxiety reduction techniques, occupa- order that develops after an individual has tional buy 100 mg desyrel free shipping anxiety symptoms in your head, and interpersonal functioning experienced or observed a traumatic or life- (American Psychiatric Association, 2000). The symptoms of the disorder may include persistent recol- Somatization disorder is a type of soma- lection of the event, sleep difﬁculties and toform disorder that is characterized by recurrent nightmares, difﬁculty in concen- recurrent, multiple physical complaints trating, and a feeling of hypervigilance or for which a medical cause cannot be increased arousal (Khouzam & Donnelly, found. Individuals may persistently reex- tressing that they impair social or occupa- perience the event in distressing images, tional function. Because physical symp- nightmares, or ﬂashbacks; they may avoid toms are often similar to symptoms of a reminders of the event, including persons variety of medical conditions, individuals or places; or they may have hyperarousal may receive medical treatment for their symptoms, such as insomnia, irritability, symptoms even though no organic cause impaired concentration, or hypervigilance can be found. Individuals may demon- Individuals with somatization disorder strate little emotion or appear detached do not consciously produce the symptoms and lose interest in previously enjoyed ac- but truly experience them, even though tivities or in important close relationships. Although many individuals experience Conversion Disorder acute forms of PTSD at some time during their life, most recover. When PTSD per- Another type of somatoform disorder is sists, it can be debilitating and require psy- conversion disorder, in which individuals chological and pharmacologic interven- lose a physical function, often related to a tion (Ursano, 2002). Symp- nature of their condition and can facilitate toms do not typically follow a pattern that recovery. Cognitive therapy and anxiety would correspond to a speciﬁc disease or management therapies can also be help- injury. Hypochondriasis Somatoform Disorders Hypochondriasis, another type of som- atoform disorder, is characterized by pre- Somatoform disorders are conditions in occupation with physical illness. Indi- which individuals experience physical viduals with this condition may fear or symptoms for which no organic cause can believe they have a serious physical illness Common Psychiatric Disabilities 189 or perceive the symptoms of a coexisting new identity without being able to recall disease or condition in an exaggerated their previous identity. For example, they may perceive a sia is the inability to recall events that cough associated with a common cold as occurred within a certain period of time a sign of tuberculosis or lung cancer. Dissociative Pain Disorder identity disorder, formerly known as multi- ple personality disorder, is a condition in Pain disorder is a preoccupation with which at least two personalities exist with- pain that is severe enough to cause in the same individual and control the impairment in function at home, school, individual’s behavior. Personality Disorders Individuals with pain disorder do not con- sciously produce the symptoms of a pain Everyone has personality traits or char- and actually experience the pain report- acteristics. This disorder can be extremely inca- they can interfere with the ability to func- pacitating, often severely limiting social tion, especially during times of crisis. Personality disorders describe disorders characterized by inﬂexible or maladaptive Factitious Disorders behaviors that have usually lasted a long time and that impair interpersonal or Although not severely disabling, a vari- occupational functioning or cause subjec- ety of other types of mental disorders may tive distress (American Psychiatric Asso- interfere with effective functioning. They may assume the sick role (American Psychiatric rationalize their actions, blaming others Association, 2000). A factitious disorder for their situation or misfortune without differs from malingering (in which indi- examining their own responsibility for the viduals also produce symptoms intention- situation at hand. When a personality disorder exists in combination with other mental Dissociative Disorders disorders, the prognosis is more guarded, and treatment and management of the Conditions in which individuals expe- personality disorder are more difﬁcult. At rience an alteration in memory, conscious- times, these individuals may not have a ness, or identity for no organic reason are full-blown personality disorder but rather called dissociative disorders. Dissociative maladaptive personality traits that may fugue is a condition in which individuals interfere with the treatment or diagnosis leave their environment and assume a of the concomitant disorder. The diagnosis of mental conditions is The most commonly used intelligence often an art as well as a science. It requires tests are the Wechsler Intelligence Scale for skill and experience on the part of those Children-Revised, the Wechsler Preschool evaluating individuals’ symptoms and and Primary Scale of Intelligence, the interpreting the results of the various tests Stanford-Binet, and the Wechsler Adult designed to measure psychological or intel- Intelligence Scale-Revised. Many professionals may The limitations of intelligence testing be involved in testing and evaluation; psy- originate from: chiatrists and clinical psychologists are fre- • the difﬁculty of tapping all aspects of quently involved in the diagnosis of intellectual ability mental disorders. Diagnosis is usually • the individual’s ability to take the test based on information from a variety of dif- • the degree to which the test measures ferent sources. There is considerable individual can be obtained through psychological variability in abilities, however, and results testing. Psychological tests may be used to of intelligence tests, like results of other evaluate intelligence, personality, or forms of psychological tests, must be eval- behavior. Much vide partial information needed for the ac- intelligence testing involves sampling curate diagnosis of a mental condition. No individuals’ intellectual capacity in a vari- single test is adequate to offer a deﬁnitive ety of different spheres. Often, because on cognitive processes, including problem mental disorders affect a variety of func- solving, adaptive thinking, and other tions, several psychological tests that aspects of performance. Tests alone should measure different functions may be nec- not determine a deﬁnitive diagnosis.
9 of 10 - Review by F. Quadir
Votes: 243 votes
Total customer reviews: 243