By J. Ugolf. Bemidji State University. 2018.
Circulatory System © The McGraw−Hill Anatomy buy 150 mg zantac with mastercard gastritis diet and treatment, Sixth Edition Body Companies zantac 300 mg lowest price gastritis forum, 2001 Chapter 16 Circulatory System 567 Ribs FIGURE 16. Pericardium of heart cecum, appendix, of aorta ascending colon, and Posterior intercostal aa. Intercostal and thoracic transverse colon muscles, and pleurae Suprarenal aa. Transverse colon, descending colon, sigmoid colon, and rectum Common iliac aa. Circulatory System © The McGraw−Hill Anatomy, Sixth Edition Body Companies, 2001 568 Unit 6 Maintenance of the Body FIGURE 16. Two branches arise from the external arterial blood to the gluteal muscles and the organs of the iliac artery, however, before it passes beneath the inguinal liga- pelvic region (fig. An inferior epigastric artery branches from the external the iliolumbar and lateral sacral arteries. The internal vis- iliac artery and passes superiorly to supply the skin and muscles ceral organs of the pelvis are served by the middle rectal and of the abdominal wall. The deep circumflex iliac artery is a the superior, middle, and inferior vesicular arteries to the small branch that extends laterally to supply the muscles at- urinary bladder. The muscles of the buttock are femoral triangle on the upper medial portion of the thigh served by the superior and inferior gluteal arteries. At this point, it is close to the surface the upper medial thigh muscles are supplied with blood from and its pulse can be palpated. The internal pudendal artery of the in- femoral artery to serve the thigh region. The largest of these, ternal iliac artery serves the musculature of the perineum and the deep femoral artery, passes posteriorly to serve the ham- the external genitalia. The lateral and medial femoral circumflex ar- blood for vascular engorgement of the penis in the male and teries encircle the proximal end of the femur and serve clitoris in the female. Circulatory System © The McGraw−Hill Anatomy, Sixth Edition Body Companies, 2001 Right lung Left lung Diaphragm muscle Heart Inferior vena cava Right kidney Left renal artery Celiac trunk Left kidney Common hepatic Abdominal aorta artery Inferior mesenteric Superior mesenteric artery artery Right common iliac artery Right external iliac artery Right external iliac vein FIGURE 16. Circulatory System © The McGraw−Hill Anatomy, Sixth Edition Body Companies, 2001 570 Unit 6 Maintenance of the Body FIGURE 16. To At the ankle, the anterior tibial artery becomes the dor- prevent a victim from bleeding to death, it is important to know sal pedal artery that serves the ankle and dorsum (superior where to apply pressure to curtail the flow of blood (fig. The pressure points for the appendages are the brachial artery on the portion) of the foot and then contributes to the formation of medial side of the arm and the femoral artery in the groin. Clinically, palpation of the dorsal plied pressure to these regions greatly diminishes the flow of blood to pedal artery can provide information about circulation to the traumatized areas below. A tourniquet may have to be applied if foot; more important, it can provide information about the bleeding is severe enough to endanger life. These vessels traverse the anterior oneal, artery to serve the peroneal muscles of the leg. At the and posterior aspects of the leg, respectively, providing blood to ankle, the posterior tibial bifurcates into the lateral and medial the muscles of these regions and to the foot. Circulatory System © The McGraw−Hill Anatomy, Sixth Edition Body Companies, 2001 Chapter 16 Circulatory System 571 FIGURE 16. The structures within the femoral triangle are shown in (a); the boundaries of the triangle are shown in (b). PRINCIPAL VEINS OF THE BODY Digital arteries arise from the plantar arch to supply the toes After systemic blood has passed through the tissue, this oxy- with blood. Knowledge Check Objective 18 Describe the venous drainage of the head, 17. Describe the clinical significance of the brachial and radial Objective 19 Describe the venous drainage of the thorax, arteries. Describe the arterial pathway from the subclavian artery to Objective 20 Describe the vessels involved in the hepatic the digital arteries. List the arteries that supply blood to the lower abdominal wall, the external genitalia, the hamstring muscles, the In the venous portion of the systemic circulation, blood flows knee joint, and the dorsum of the foot.
As a result generic zantac 150mg without prescription gastritis gel diet, the the apical surface of the cell buy zantac 300 mg cheap gastritis diet wiki, where iodination takes place. The iodide used for iodination of the thy- Thyroid Hormones Are Formed From the roglobulin precursor protein comes from the blood perfus- Hydrolysis of Thyroglobulin ing the thyroid gland. The basal plasma membranes of fol- licular cells, which are near the capillaries that supply the When the thyroid gland is stimulated to secrete thyroid follicle, contain iodide transporters. These transporters hormones, vigorous pinocytosis occurs at the apical mem- move iodide across the basal membrane and into the cy- branes of follicular cells. The iodide transporter is an ac- brane reach into the lumen of the follicle, engulfing bits of tive transport mechanism that requires ATP, is saturable, the colloid (see Fig. Endocytotic vesicles or colloid and can also transport certain other anions, such as bro- droplets formed by this pinocytotic activity migrate to- mide, thiocyanate, and perchlorate. Lysosomes, cell to concentrate iodide many times over the concentra- which are mainly located in the basal region of resting fol- CHAPTER 33 The Thyroid Gland 599 Blood Follicular cell Lumen Tight junction Iodination and - coupling I MIT I- I- H2O2 Tg DIT Iodide T4 Tg transporter T3 Thyroglobulin (Tg) ER precursor Golgi Deiodination Endosomes Micropinocytosis DIT MIT T4 T4 Macropinocytosis Colloid T3 T3 Proteolysis droplet Secretion Lysosomes Pseudopod FIGURE 33. The lysosomes fuse with the colloid droplets with a buffer against drastic changes in circulating thyroid and hydrolyze the thyroglobulin to its constituent amino hormone levels as a result of sudden changes in the rate of acids. As a result, T4 and T3 and the other iodinated amino T4 and T3 secretion. T4 and T3 formed from the roid hormones have long half-lives in the bloodstream. The DIT and MIT Thyroid Hormones Are Metabolized by generated by the hydrolysis of thyroglobulin are deiodi- Peripheral Tissues nated in the follicular cell. The released iodide is then re- utilized by the follicular cell for the iodination of thy- Thyroid hormones are both activated and inactivated by roglobulin (see Fig. The en- zymes that catalyze the various deiodination reactions are Binding of T4 and T3 to Plasma Proteins. Most of the T4 regulated, resulting in different thyroid hormone concen- and T3 molecules that enter the bloodstream become trations in various tissues in different physiological and bound to plasma proteins. Each molecule of TBG has a sin- cretory product of the thyroid gland and is the predominant gle binding site for a thyroid hormone molecule. However, about 40% of the maining T4 and T3 in the blood are bound to transthyretin T4 secreted by the thyroid gland is converted to T3 by enzy- or to albumin. Less than 1% of the T4 and T3 in blood is in matic removal of the iodine atom at position 5 of the thyro- the free form, and it is in equilibrium with the large protein- nine ring structure (Fig. It is this small amount of free thyroid hor- 5 -deiodinase (type 1) located in the liver, kidneys, and thy- mone that interacts with target cells. The T3 formed by this deiodination and that se- The protein-bound form of T4 and T3 represents a creted by the thyroid react with thyroid hormone receptors large reservoir of preformed hormone that can replenish in target cells; therefore, T3is the physiologically active form the small amount of circulating free hormone as it is of the thyroid hormones. A second 5 -deiodinase (type 2) is 600 PART IX ENDOCRINE PHYSIOLOGY NH 2 DIT free Regulation of 5 -Deiodination. The 5 -deiodination reac- CH2 CH radicals tion is a regulated process influenced by certain physiolog- O CO ical and pathological factors. The result is a change in the relative amounts of T3 and reverse T3 produced from T4. O NH CH CH For example, a human fetus produces less T3 from T4 than 2 CO a child or adult because the 5 -deiodination reaction is less active in the fetus. Also, 5 -deiodination is inhibited during fasting, particularly in response to carbohydrate restriction, Radical addition but it can be restored to normal when the individual is fed again. Trauma, as well as most acute and chronic illnesses, NH Quinoid also suppresses the 5 -deiodination reaction. Under all of CH2 CH intermediate these circumstances, the amount of T3 produced from T4 is O CO reduced and its blood concentration falls. However, the O amount of reverse T rises in the circulation, mainly be- NH 3 CH2 CH cause its conversion to 3,3 -diiodothyronine by 5 -deiodi- CO nation is reduced. A rise in reverse T3 in the blood may sig- nal that the 5 -deiodination reaction is suppressed.
A connective sheath which is separated from the perios- tissue plate zantac 150 mg on-line gastritis reflux diet, the denticulate ligament (A17) cheap 300 mg zantac with amex gastritis untreated, teum-like lining of the vertebral canal, the extends on both sides of the spinal cord endorhachis (A4), by the epidural space (A5). Forthispurpose,withthepatientbending cushion for the dural sac, which moves to- over, a needle is deeply inserted between the gether with the vertebral column and the processes of the second to fifth lumbar vertebrae head. Bending the head pulls the dural sac until CSF begins to drop (lumbar puncture) (E). The arachnoidea borders closely onto the inner surface of the dura mater. It forms the boundary of the subarachnoidal space (AC11), which is filled with cerebrospinal fluid (CSF). Between the inner surface of the dura and the arachnoidea lies a capillary cleft, the subdural space, which widens into a real space only under pathological conditions (subdural bleeding). Dura and arachnoidea accompany the spinal roots (AC12), pass with them through the intervertebral foramina, and also envelope the spinal gan- glia (AC13). The dura then turns into the epineurium (A14), and the arachnoidea into the perineurium (A15) of the spinal nerves. The part of the root leaving the vertebral canal, the radicu- Kahle, Color Atlas of Human Anatomy, Vol. Spinal Meninges 65 11 22 33 44 55 1111 1313 1717 1212 1414 1616 1515 A Position of the spinal cord in the vertebral canal, cross section (according to Rauber-Kopsch) 1313 1212 B Cauda equina 77 1313 66 1616 1111 C Dorsal view of root, radicular nerve, and spinal ganglion 88 99 1010 D Cervical spinal cord with neck flexed and extended (according E Lumbar puncture to Breig) Kahle, Color Atlas of Human Anatomy, Vol. The vertebrate body, with the exception of The loss of a single posterior root cannot be the head, is originally subdivided into seg- demonstrated for touch sensation, since the ments or metameres. The vertebrae, ribs, and corresponding dermatome is also supplied intercostal muscles can be regarded as rem- by the neighboring posterior roots. However, the spinal fibers join to form the spinal nerves as they emerge through the metameric intervertebral foramina, thus creating an apparent second- ary segmentation. The sensory fibers of the spinal nerves supply stripe-shaped zones of the skin, called dermatomes in analogy to myotomes and sclerotomes. This, too, is a secondary segmentation and reflects the in- nervation of each dermatome by a single posterior root (segmental innervation). Clinical Note: The dermatomes play an im- portant role in the diagnosis and localization of spinal cord injuries. Loss of sensibility in certain dermatomes indicates a specific level of injury in the spinal cord. Simplified reference points are the line through the nipples, regarded as the boundary between T4 and T5, and the groin, re- garded as the boundary between L1 and L2. The first cervical spinal nerve has no sensory repre- sentation on the body surface, for the spinal gan- glion of its posterior root is absent or rudimen- tary. There are slightly different segmental boundaries for various modalities, such as touch and pain, and for sweating and piloerection. The diagram (A) was designed according to the decrease in sensibility (hy- poesthesia) resulting from disk prolapse; it shows how the dermatomes extending around the trunk become elongated in the limbs. They become translocated to the distal limb areas during embryonic development when the limbs are budding (C). Thedermatomesoverlaplikerooftiles,asil- lustrated by the shift in boundaries that have been determined according to the ex- Kahle, Color Atlas of Human Anatomy, Vol. Dermatomes 67 C 2 C 3 C 3 C 4 C 4 C 5 C 5 C 6 C 6 T 1 C 7 C 8 A Dermatomes T 3 T 1 (according to T 6 Keegan and Garrett) T 6 T 12 T 9 L 1 L 3 C 5 C 6 L 5 C 6 T 12 C 7 L 1 C 8 L 2 C 7 S 1 S 2 L 3 C 8 S 3 S 2 S 3 L 4 L 5 C 3 C 4 C 5 S 1 T 1 T 2 S 1 3 L 5 4 S 2 L 4 5 6 7 8 C 3 3 9 4 4 3 10 5 5 4 11 6 6 5 7 7 7 6 L 1 12 8 8 8 1 T 1 1 2 2 2 3 L 2 3 L 3 3 B Overlap of dermatomes (accord- C Development of dermatomes in ing to Förster) the upper limb (according to Bolk) Kahle, Color Atlas of Human Anatomy, Vol. The anatomy of the spinal cord causes very However, pain and temperature sensations specific patterns of functional deficiencies are lost (analgesia and thermoanesthesia), be- after injury; depending on the site of lesion, cause their fibers, which cross through the different pathways and therefore different white commissure, are interrupted (C5). Complete transection (A) cuts off all de- scending motor pathways, causing complete paralysis below the injured level. At the same time, it interrupts all ascending path- ways, causing a complete loss of all sensa- tions. If the lesion is above the sacral spinal cord, it results in the loss of voluntary con- trol over urination and defecation. If the le- sion lies above the lumbar enlargement, both lower limbs are paralyzed (paraplegia), and if it lies above the cervical enlargement, both upper limbs are also paralyzed (tet- raplegia).
The neck region is apparent 150 mg zantac with mastercard gastritis chronic nausea, and the ab- Knowledge Check domen is less prominent safe 300mg zantac gastritis university of maryland. Briefly summarize lids are stuck together to protect against probing fingers during the structural changes that occur in an embryo between muscular movement. The nostrils are developed but plugged the fourth and eighth weeks of development. Identify the fetal and maternal components of the placenta bryonic period—yet, well into this period many women are still unaware that they are pregnant. For this reason, a woman should ab- and describe the blood circulation in these two components. Developmental © The McGraw−Hill Anatomy, Sixth Edition Development Anatomy, Postnatal Companies, 2001 Growth, and Inheritance 770 Unit 7 Reproduction and Development Van De Graaff: Human VII. Developmental © The McGraw−Hill Anatomy, Sixth Edition Development Anatomy, Postnatal Companies, 2001 Growth, and Inheritance Chapter 22 Developmental Anatomy, Postnatal Growth, and Inheritance 771 Van De Graaff: Human VII. Developmental © The McGraw−Hill Anatomy, Sixth Edition Development Anatomy, Postnatal Companies, 2001 Growth, and Inheritance 772 Unit 7 Reproduction and Development FIGURE 22. Ossifi- FETAL PERIOD cation centers appear in most bones during the ninth week. Dif- The fetal period, beginning at week 9 and culminating at birth, is ferentiation of the external genitalia becomes apparent at the characterized by tremendous growth and the specialization of end of the ninth week, but the genitalia are not developed to the body structures. It can swallow, digest the fluid that passes the fetal period of development. Its nervous system and muscle coordination are developed Objective 12 Describe the various techniques available for to the point that it will withdraw its leg if tickled. Because most of the tissues and organs of the body form during Major structural abnormalities, which may not be predictable from genetic analysis, can often be detected by ultrasonogra- the embryonic period, the fetus is recognizable as a human being phy (fig. The fetus is far less vulnerable than the embryo to waves that reflect back in a certain pattern determined by tissue den- the deforming effects of viruses, drugs, and radiation. For example, sound waves bouncing off amniotic fluid will pro- ferentiation and organ development continue during the fetal duce an image much different from that produced by sound waves bouncing off the placenta or the mother’s uterus. For the most part, fetal so sensitive that it can detect a fetal heartbeat several weeks before development is primarily limited to body growth. Structural Changes in the Fetus by Week Thirteen to Sixteen Weeks By the thirteenth week, the facial features of the fetus are well Changes in the external appearance of the fetus from the ninth formed, and epidermal structures such as eyelashes, eyebrows, through the thirty-eighth week are depicted in figure 22. During Nine to Twelve Weeks the sixteenth week, the fetal heartbeat can be heard by applying At the beginning of the ninth week, the head of the fetus is as a stethoscope to the mother’s abdomen. The eyes are widely spaced, and the sixteenth week, the fetus is 140 mm long (5. Developmental © The McGraw−Hill Anatomy, Sixth Edition Development Anatomy, Postnatal Companies, 2001 Growth, and Inheritance Chapter 22 Developmental Anatomy, Postnatal Growth, and Inheritance 773 Five weeks Six weeks Seven weeks Eight weeks Ten weeks Twelve weeks Fourteen weeks FIGURE 22. After the sixteenth week, fetal length can be determined from vernix caseosa in place on the skin and produces a ciliary-like radiographs. The reported length of a fetus is generally de- motion that moves amniotic fluid. It is also thought to help de- rived from a straight-line measurement from the crown of the head to the developing ischium (crown-rump length). A 20-week-old fetus is about 190 mm on an embryo prior to the fetal period, however, are not reported as (7. Between the seventeenth and twentieth weeks, the legs achieve Twenty-One to Twenty-Five Weeks their final relative proportions, and fetal movements, known as quickening, are commonly felt by the mother. The skin is cov- Between the twenty-first and twenty-fifth weeks, the fetus in- ered with a thin, white, cheeselike material known as vernix creases its weight substantially to about 900 g (32 oz). It consists of fatty secretions from the seba- length increases only moderately (240 mm), however, so the ceous glands and dead epidermal cells. The skin is quite wrinkled and is caseosa is to protect the fetus while it is bathed in amniotic fluid. Because the blood flowing in the capillaries is now Twenty-week-old fetuses usually have fine, silklike fetal hair visible, the skin appears pinkish. Lanugo holds the Twenty-Six to Twenty-Nine Weeks Toward the end of this period, the fetus will be about 275 mm vernix caseosa: L. Developmental © The McGraw−Hill Anatomy, Sixth Edition Development Anatomy, Postnatal Companies, 2001 Growth, and Inheritance 774 Unit 7 Reproduction and Development (a) Nose Trunk FIGURE 22. Toward the end of most pregnancies, the weight of the fetal head causes the body to rotate, positioning the head against the cervix of the uterus.