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ВСТУПЛЕНИЕ 11 страница




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constituent, precisely, glomeruli, distinguishable, regardless, exces­sive, composition, exception

Упражнение 3. Прочтите текст В (10 мин). 1) Разделите его на 2 части и назовите тему каждой части. 2) Найдите предложения: а) со сложным подлежащим; б) со словами aswell, aswellas. 3) Переведите эти предло­жения.

Text В

The Excretory Function of the Kidney

It has long been known that the kidney does not manufacture fully the elements which compose the urine. It is known only to extract them unchanged from the blood plasma where, with very few exceptions, they already exist. In other words, the urinary function is the excretion, but the kidney is found to exercise a choice among the numerous organic substances present in the circulating bloodi Some substances, such as the proteins, are wholly retained in the organism, although the blood plasma contains a high concentration of them (70 to 80 grams per litre). Others are entirely taken away by the kidney as well as eliminated through the urine: this is the case with certain foreign bodies such as penicillin or streptomycin as well, which the organism eliminates by means of the kidney. Most of the constituents of the plasma are excreted in the urine in variable proportions; the quantities thus taken away by the kidney are not fixed and vary even from day to day for each substance eliminated. If the amount of salt absorbed is very great or very small, the concentra­tion of salt in the blood and the total amount of salt in the individual as well will not vary at all; if practically no salt is absorbed, no salt will be eliminated; if much salt is absorbed its rate of elimination will rise, until after a few days it exactly counterbalances the excess taken in; the quan­tity of salt taken away by the kidney will be equal to the excess received.

Finally, we may ask ourselves what internal instrument may change at every moment the rate at which each constituent of the blood plasma is taken away by the kidney.

The basic instrument of this mechanism seems to be the nephron. Each kidney is formed of about a million nephrons, joined by an inter­stitial tissue through which the blood vessels as well as nerves pass. Thus the nephron is the morphological and functional unit of the system determining the composition of the urine. Its structure is not very simple. The glomerulus, a small bundle of arterial capillaries en­closed in a small round capsule, forms the head of the nephron. Al­though the glomeruli are small and hardly distinguishable by the naked eye1, the total quantity of blood which passes through them every minute is very great: over a litre for the two kidneys of an adult, which


is at quarter of the total blood distributed to all the rest of the organism in the same time.

Tnis is the first stage in the production of urine, known as glomerular filtration.

Physiologically the' kidney must not be regarded as just an organ for the formation of urine, wastes. The kidney appears to be the chief con­troller of the delicate chemical balance necessary to life.

Notes

1. by the naked eye невооруженнымглазом

Упражнение 4. Найдите в тексте В предложения, более полно выражающие мысль данных суждений, и прочтите их.

1. The kidney doesn't manufacture the elements which compose urine. 2. The urinary function is that of excretion. 3. Some substances are retained in the organism. 4. Penicillin is eliminated through the urine. 5. The basic instrument of the kidney is the nephron.

Часть III

Контрольно-обобщающие упражнения к уроку 11

Упражнение 1. Найдите и переведите предложения со сложным подлежащим.

1. The chief functiqikof the kidneys is to separate fluid and certain solids from the blood. 2. The excretion of urine is thought to be possible by the selective action of the cells of the kidney tubules. 3. When tl\e kidneys fail to act solid waste substances accumulate in the blood.(j2> The formation of urine is found to begin in the glomerulus as water salts, sugar, urea and other wastes. 5. Streptococci do not seem to cause glomerular inflammation by direct invasion. 6. After the first two weeks of acute nephritis patients usually appear to make a complete recovery.

(Ответ: 2, 4, 5, 6. Если вы ошиблись, повторите § 27 Граммати­ческого справочника.)

Упражнение 2. Укажите, в каких предложениях asweDas, aswell: а) состав­ной союз; tf) наречие. Переведитепредложения.

1. Acute glomerular nephritis may involve various systems of the body as well as the glomerular tufts. 2. Specific gravity is a measurement that reflects the amount of wastes as well as minerals in the urine. 3. Acids as

well as other substances which the body does not need are secreted into the distal renal tubules from the blood stream. 4. Drugs can be obtained from plants, animals and chemical substances as well. 5. While examin­ing a patient the doctor was asking him about his previous and present condition as well.

(Ответ:a) 1, 2, 3; b) 4, 5. Если вы ошиблись, повторите § 41 Грамматического справочника.)

Упражнение 3. Переведите на английский язык производные от данных слов.

1. excrete— выделение, выделительный, экскреция; 2. active— ак­тивность, активно, деятельность; 3. constitute- составная часть, те­лосложение; 4. urine— мочевой, мочеиспускание, урология; 5. sweat— потеть, потение, потный, потовые (железы)

(Ответ: 1. excretion, excretory, excretion; 2. activity, actively, activities; 3. constituent, constitution; 4. uric (urinary), urination, urology; 5. to sweat, sweating, sweaty, sweat (glands).)

Упражнение 4. Дайте синонимы к следующим словам.

1. to eliminate; 2. waste products; 3. manner; 4. to take place; 5. quantity (Ответ: 1. to excrete; 2. waste matter (wastes); 3. way; 4. to occur; 5. amount.)

Упражнение 5. Образуйте словосочетания, используя слова из пунктов а) и б). Переведитеих.

а) 1. to eliminate; 2. to carry out; 3. to excrete; 4. to get rid of; 5. to throw out; 6. excretory; 7. activity (of);

б) 1. the excess of water (constituents); 2. organ(s); 3. action; 4. the kidneys and skin; 5. sweat glands; 6. muscular; 7. the function; 8. waste products

(Ответ: 1-1, 8; 2-1, 7, 8; 3-1, 8; 4-1, 8; 5-1, 8; 6-2, 3; 7-4, 5, 6.)

LESSON TWELVE

THE ENDOCRINE SYSTEM

1. Сложное дополнение (§ 26)

2. Составныесоюзыeither ... or; neither ... nor; so ... that; not only ... but (§ 40)

1 J Less6n 12^ 145

i / у ,j . Часть11

j ' • v

1 Слова к части I

I

activity [ak'tiviti]n(обыкн.pi.) nде­ятельность arouse [a'rauz] vвозбуждать voluntary [votantari] а произвольный involuntary [in'votantari] а непроиз­вольный

thyroid ['6airoid] nщитовидная же­леза

emergency [I'msicfesnsi] nтяжелое состояние больного, требующее немедленной помощи; экстрен­ная необходимость

Упражнения

Упражнение 1. Переведите следующие предложения с конструкцией «слож­ное дополнение» на русский язык.

1. We know nephron to be the histological kidney unit. 2. A great deal of experimental work showed a dilute urine to be filtered by the glomeruli and the tubules to have an absorption function. 3. The exper­imentalists found the decrease in body temperature to increase urinary secretion. 4. Bowman in 1842 found organic constituents to be secreted by the cells of the convoluted tubules. 5. Scientists found glomerular filtration to occur in all vertebrate kidneys.

Упражнение 2. Замените следующие придаточные предложения конст­рукцией «сложное дополнение». , ,

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1. We know that glomeruli ao^-absent in certain fishes. 2. Most phys­iologists believe №kt the phenomenon of urinary secretion is due to filtration of the llon-colloid constituents of the plasma through the glom­erulus. 3. Some investigators thought the rate of flow was-a para­mount factor governing renal secretion. 4. The doctor supposed that the

l V

rise of blood pressure caused increased urination. 5. Scientists consider that a balanced diet is necessary for everybody. / r

removal [ri'murvl] nудаление, уст­ранение fail [feil] vотказать в действии, про­валиться, не удаться failure ['feilja] п недостаточность, остановка, разрыв, провал, не­удача duct [dAkt]п проход; проток, канал affect [a'fekt] vвлиять на, поражать (болезнью); воздействовать measure['тезэ] п мера; vизмерять

г-'Д ,

Упражнение 3. Прочтите и переведите следующие предложения с со­ставными союзамиeither... or, neither... nor, notonly... but (also), so... that. /

£> ; < ' г .л


1. Experimental work has shown that removal of one-half, two-thirds and sometimes three-fourths of the kidney substances in the dog produc­es changes neither in urinary volume nor in urinary nitrogen. 2. дЪеlecturer demonstrated that in the frog's kidney indigo carmine, neutral red and ferric ammonium citrate not only appear in the glomerular fil­trate but also in proportion to their concentrations in the serum. 3. The decreased rate of glomerular secretion results in its slower passage through the tubules so that water absorption is more complete. 4. The percentile chloride may either increase or decrease, but the total excretion is always greater.

Упражнение 4.Заполнитепропускисоставнымисоюзамиeither ... or, nei­ther ... nor, not only ... but, so ... that.

1. The cations Кand Ca induce diuresis when administered ... to­gether ... in succession. 2. The kidney is an organ capable of altering the

quantity and quality of the urine secreted......... the water balance and

osmotic relations in the blood and tissues are kept within optimal rang­es. 3. The functions of the kidney are .»jnumerous ... they require a high degree of correlation as well. 4. ... our group ... group 5 decided who will be the first to begin the experimental work on glomerular filtration.

Упражнение 5. Отработайте чтение следующих слов и словосочетаний.

endocrine ['endoukrain], similarly ['simitali], medulla [теЧЫэ], ad­renal [ad'riinsl], failure [Teiljd], insufficient [inss'fijsnt], hypophysis [hai'pofisis]

Упражнение 6. Образуйте слова согласно модели и переведите их. Запом­нить значение суффикса-izeи приставкиinter-.

1. Прилагательное, существительное + -ize (-ise) = глагол:

oxideокись — tooxidizeокислять.

active, material, populat, crystal, immune, special

2. inter- + существительное, прилагательное, глагол = производ­ное слово, обозначающее взаимодействие, взаимовлияние, поло­жение между...: toactдействовать — tointeractвзаимодействовать.

change, to connect, coastal, national, action, auricular, cellular, clavical

Упражнение 7. Прочтите и переведите данные гнезда слов.

1. to act, action, activity, activities, to activize; 2. to emerge, emergence, emergency, emergent; 3. to fail, failure, failing; 4. to
ihsturb, disturbance, disturbed; '5. to suffice, sufficient, sufficiency, efficiently

Vпражнение 8. Прочтите и переведите следующие словосочетания.

to put into action, in case of emergency, emergency case, movable kidney, heart failure, failing sight, to measure out a spoonful of medicine

Упражнение 9. Просмотрите текст А. Разделите текст на смысловые части.


 


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■ -I *

Text АEndocrine Glands


 


1. There are two organ systems — the nervous system and the endo- i rines - which coordinate the activities of all others. Almost nothing can happen to the body anywhere without appropriate response either motor or perceptual, voluntary or involuntary. Similarly, various parts of the endocrine system act upon each other and other organs, stimulating them I оdo their special jobs. Thus, the thyroid gland stimulates the metabolism of all bodily parts. The adrenal medulla mobilizes the activities of many organ systems in case of the emergency. And the adrenal cortex exercises control over many body functions, so important that its removal results in

failure of the functions and the death of the animal.

Pituitary gland
Testes in male
Fig. 12.The endocrine system.
Pineal gland Parathyroid glands (four glands)
Thyroid gland Thymus gland
Adrenal glands

2. Endocrine glands or glands of internal secretion are ductless glands, that is, they empty their secre­tions — chemical substances called hormones (from the Greek word «hormao» — excite) — directly into the blood stream. The hor­mones are carried through­out the organism with the blood and are delivered to various organs whose ac­tivity they either stimulate or depress. Neither single hormone nor endocrine gland acts wholly by itself at any time.

3. We know hormones to play a very important part in the organism. Many of them affect metabolism and the activity of the cardiovascular and other systems. A disturbance in the activity of the endocrine glands is accompanied by changes throughout the organism. These changes may be not only due to an increase in the function of a gland (hyper- function) but to a decrease (hypofunction).

4. A hyperfunctioning gland secretes a superfluous amount of hor­mones and a hypofunctioning gland secretes an insufficient amount. The amount of hormones produced by the endocrine glands in 24 hours measures fractions of a milligram.

5. The functions of all the endocrine glands are interconnected so that the glands make up a single system. Physiologists consider the hypophysis to be the chief gland of this system; they consider it to produce special substances which stimulate the activities of other endocrine glands.

6. The activities of endocrine glancjs are regulated by the nervous

i

system. It is known to exercise direct control over the endocrine glands through the nerves and neurohumoral control, particularly through the hypophysis. The hormones in their turn ^ffect the functions of the dif­ferent parts of the nervous system. . . ч ^ o ,

Упражнение 10. Прочтите и переведите текст А. Первый абзац переведите письменно.

j.■ . •, ,

Упражнение 11. Найдите в тексте ответы на следующие вопросы и зачи­тайте их.

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1. The functions of various endocrine glands are different, aren't they? What are they? 2. Is the disturbance in the activity of the endo­crine glands accompanied by any changes throughout the organism? 3. What is hyper- or hypofunction? 4. Why is hypophysis considered the chief gland of the endocrine system? 5. Howdotheendocrineandnervoussystemsinteract?

Упражнение 12. Найдите ключевые предложения в каждой смысловой части текста А и выпишите их.

Упражнение 13. Найдите в каждом ряду слово, перевод которого дан в начале ряда.

1. деятельность — activator, activities, activation, activity, activist;

2. подобнымобразом, также — similarity, similar, simple, similarly;

3. такимобразом, так — so, then, thus, actually; 4. влиятьна... — to effect, to defect, to affect


Упражнение 14. Прочтите и переведите данные предложения. Определите, какой частью речи являются выделенные слова.

1.Thus the thyroid gland stimulates metabolism. 2. Hormones affect metabolism and the function of the cardiovascular system. 3. The func­tions of endocrine glands are interconnected. 4. The nervous system exercises direct control over the endocrine glands through the nerves and neurohumoral control. 5. The hormones either stimulate or depress the activity of various organs. 6. The activities of endocrine glands are regu­lated by the nervous system.

Упражнение 15. Переведите следующие предложения. Определите функции инфинитива

1. The methods developed to establish special aspects of endocrinol­ogy have become diversified and complicated. 2. The existence of many hormones to be discussed must be regarded as probable rather than demonstrated with certainty. 3. The hypophysis is believed to be the chief endocrine gland. 4. The chief action of the thyroid hormone is to accelerate all oxidations, particularly those of fat and protein. 5. The discharge of thyroid hormone appears to be guided by a thyrotropic pituitary hormone. 6. The scientists believe insulin and anterior pitu­itary hormones to exert contrary actions on the blood sugar level.

Упражнение 16. Переведите следующие предложения. Запомните значение парных союзовeither... or, neither... nor, so... that, notonly... but.

1. The observations of surgeons on thyroid deficiency revealed that internal secretions are not only necessary for proper growth and nutri­tion but for normal mental development as well. 2. An excess of the somatotropic hormone, either due to hypersecretion or injection of ex­tracts, causes gigantism and leads to acromegaly in adults. 3. The mo­lecular weight of insulin is so great that prospects of its synthesis seem very remote. 4. While asked the student could neither describe nor show the pineal gland in figure 12.

Упражнение 17. Переведите данные предложения на английский язык письменно.

1. Нервная и эндокринная системы координируют и стимулиру­ют деятельность организма. 2. Эндокринные железы не имеют про­токов и выделяют свой секрет непосредственно в кровь, которая разносит его по организму. 3. Снижение функции или понижение

активности эндокринных желез вызывает изменения в работе всего организма. 4. Деятельность всех эндокринных желез взаимосвязана и регулируется гипофизом. 5. Нервная система контролирует рабо­ту эндокринных желез.

Часть II

Слова к части II

intermediate [,inta'mi:dj9t]апроме-dilute [daflju:t] v разбавлять, разво-

жуточный, средний дить

border ['bo:dd]п край; граница excessive [ik'sesiv]а избыточный,

setп ряд, серия; набор чрезмерный

intensify [in'tensifai] vусиливать

Упражнения

Упражнение 1. Прочтите и переведите следующие слова.

hypothalamus, anterior, intermediate, posterior, microscope, fibre, secretion, circulation, neurons, neurohumoral, gigantism, acromegaly, oxitocin, to intensify

Упражнение 2. Найдите в данном ряду слово или словосочетание, значение которого дано в начале ряда.

1. поскольку — in so far as, so far as, as far as; 2. серия, ряд — row, line, series, set; 3. тоесть — all that, so that, that is, that is why

Упражнение 3. Найдите в данном ряду слово или словосочетание, синонимичное данному в начале ряда.

1. fairly - rather, too, enough, actually, completely; 2. to break up — to believe in, to end, to divide into...; 3. adults — teenagers, children, the old, grown-ups; 4. insufficient — enough, lacking, deficient, excessive

Упражнение 4. Запомните значение сочетаний со словомthat.

that is the point вэтомсутьдела

that is to say тоесть

thatiswhy вот почему

nowthat теперь, когда

Упражнение 5. Прочтите текст В (10 мин). 1) Разделите его на три смысловые части. 2) Найдите предложения: а) с конструкцией «сложное

юполнение»; б) с парными союзами either...or, neither...nor, so... that, notonly...but. 3) Переведите эти предложения.

Text ВHypophysis (the Pituitary)

We know the hypophysis to be a small oval body weighing about 0,5 g; it is located in the cranial cavity and is connected with the hypothalamus. The gland consists of an anterior lobe, an intermediate part and a poste­rior lobe; the borders between them can be seen only under the micro­scope. Experimental and clinical observations strongly suggest anterior lobe to be necessary for proper growth to adult stature, for normal devel­opment and function of the reproductive system and for control the ac­tivities of other endocrine glands. The posterior lobe remains connected to the brain by means of the pituitary stalk, through which nerve impulses travel from the hypothalamus. The anterior lobe, so far as is known, r eceives no nerve fibres of any kind, and its control must then depend on t he presence of substances in the blood. In spite of all this, there appears to be a way whereby the brain can exercise a fairly direct control over the anterior lobe. The blood vessels leading to the hypothalamus break up into capillaries; having passed through these capillaries, the blood is gath­ered into small veins; these veins pass downward so that they open into another set of capillaries in the anterior lobe. This is called the hypotha­lamic-hypophyseal portal system. Excision of the anterior hypophysis neither alters the lipid content of the liver nor inhibits the accumulation of large amounts of lipids in the liver.

The hypothalamus has been found to secrete special substances which regulate the secretion of the hypophyseal hormones. The activities of the other endocrine glands are thus subject to neurohumoral regulation through the hypophysis.

Disfunction of the anterior lobe of the hypophysis is accompanied by changes throughout the organism. For example, excessive secretion of the growth hormone in childhood results in gigantism. Such people may grow to a height of 2,5-2,6 m. Excessive secretion of this hormone in adults results not only in excessive growth of the bones of the face, fingers and toes, but in enlarged nose, tongue and certain other organs. This disease is called ac­romegaly. Insufficient secretion of the growth hormone in childhood is ac­companied by retarded growth (dwarfism). It is a relatively rare condition iissociated with either early atrophy or absence of the anterior lobe.

The posterior lobe of the hypophysis secretes oxytocin and vasopressin. Physiologists consider oxytocin to intensify the contractions of the uter­ine muscles and it is therefore used to boost weak labour. We know vasopressin to cause constriction of the blood vessels, especially those of the uterus.

Упражнение 6. Прочтите следующие суждения. Найдите в тексте В пред­ложения, более полно выражающие мысль данных суждений, и прочти­те их.

1. The hypophysis is connected with hypothalamus. 2. There are two lobes in the gland. 3. Hypothalamic-hypophyseal portal system of blood vessels supplies blood to the anterior lobe of the hypophysis. 4. Hypo­physis regulates the activity of other endocrine glands. 5. Disfunction of the anterior lobe of the hypophysis is accompanied by changes of differ­ent kind throughout the organism.

Часть III

Контрольно-обобщающие упражнения к уроку 12

Упражнение 1. Найдите и переведите предложения со сложным дополне­нием.

1. Thyroxine is necessary in the body to maintain a normal level of metabolism in all body cells. 2. Parathyroid hormone causes calcium to leave bone tissue and enter the blood stream. 3. Removal of the thymus gland is found to be helpful in treatment of muscular-neurological disor­ders. 4. Cells need oxygen to carry on metabolic processes.5. We know the pituitary gland to be also called the hypophysis. 6. Pituitary growth hormone acts on bone tissue to accelerate its growth in the body.

(Ответ: 2, 5. Если вы ошиблись, повторите § 26 Грамматического справочника.)

Упражнение 2. Укажите, в каких предложениях использованы составные союзы.


1. Insulin is necessary in the blood stream so that sugars can pass from the blood into the cells of the body. 2. In acute nephritis some glomeruli are more severely involved than others, but practically no glomerulus escapes some injury. 3. Treatment of thyrotoxicosis may include either thyroidectomy or management with antithyroid drugs. 4. The ovaries are held in place on either side of the uterus by the utero-ovarian ligaments. 5. In his last report the professor spoke neither of hyperfunction nor hvpofunction of endocrine glands'. 6. Overproduction of glucocorticoids leads not only to obesity, moonlike fullness of the face but also to elevat­ed blood sugar, high blood pressure and weakness (fatigue).

(Ответ: 1, 3, 5, 6. Если вы ошиблись, повторите § 40 Граммати­ческого справочника.)

Упражнение 3. Расшифруйте данные сокращения, i., f., oz(s), g., lb., 1., ml., cm.

(Ответ:inch, foot (pi feet), ounce(s), gramme (gram), libra(nam. дляpound), litre, millilitre, centimetre.)

Упражнение 4. Опишите функции эндокринных желез, используя рис. 12.

LESSON THIRTEEN

THE NERVOUS SYSTEM

1. Герундий (§ 23)

2. ing-формы в различных функциях (§ 24)

--------------------------------------------------------------------------------- г------------------------------------------------------------------------------ -V-

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Часть I л Ь

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Слова к части I


 


actually ['aektjuali]advдействитель­но, фактически touch [UtJ] vтрогать, касаться bundle[ЪлгкИ] п пучок, узел cerebrum ['seribram] п головной мозг cerebellum[ seri'belam] п мозжечок feel [fi:l] vчувствовать, ощущать feelingп чувство, ощущение treat [tri:t] vлечить; обрабатывать;

обращаться treatment ['triitmsnt] п лечение, те­рапия; обработка; обращение


 


Упражнения

Упражнение 1. Переведите следующие предложения с герундием.

1. Stimulating the somatotropic hormone upon growth can be partly correlated with its acceleration of metabolism. 2. Certain researchers believe that the hypophysectomized animal differs essentially from the normal in that it has lost the power of converting fateto carbohydrates. 3. In acromegaly and gigantism X-ray pictures re9fr&iLfre?pening the pituitary fossa of the sphenoid bone. 4. The thyroidectomy is removing the thyroid gland. 5. Thyroxine and the somatotropic pituitary hormone

are regarded as basic metabolic hormones necessary for maintaining general nutritive conditions.

Упражнение 2. Найдите ing-формы в следующих предложениях. Переведитепредложения.

1. Thyrotropic hormone is of considerable importance not only in regulating the thyroid secretion but in accounting for many metabolic effects. 2. Related injections of extracts containing ketogenic hormones cause fat infiltrations of liver, reduction in fat of other tissues and keto- sis. 3. The stimulating action of the somatotropic hormone upon growth can be partly correlated with its acceleration of metabolism. 4. Injecting hormones into normal young animals results in animals of large size and precocious sexual development. 5. Acromegaly and gigantism produce overgrowing of bones and there may be an actual lengthening of the spinal column.

Упражнение 3. Отработайте чтение следующих слов.

nerve [na:v], touch [UtJ], actually ['aektjuali], area ['еэпэ], ether ['i:6dL anesthetics [,aenis'0etiks], novocaine ['nouvokein], yawning [p:nir)]

Упражнение 4. Прочтите и переведите следующие Словосочетания.

1. to react upon each other, reaction power, the reaction of eye to the light, Wasserman reaction, reaction of sensibility; 2. to feel one's pulse, to feel like doing smth, to feel tired, to feel fine, a feeling of danger; 3. to treat with penicillin, surgical treatment, treatment by exercises, to try many treatments for pneumonia, to be under treatment

Упражнение 5. Просмотрите текст А и сравните по содержанию обе части текста.

Text А

The Nervous System. Brain and Nerves

1. Nerves lead from the spinal cord or from the brain to each part of the body. Then they lead from each part of the body back to the brain or spinal cord. The brain and spinal cord are the centres of this system of nerves.

2. All parts of your body are connected by nerves. The nerve cells with their fibres make up the nervous system. When we study one

nerve cell, we see that it has a long^ fibre at one end and short fi­bres at the other. The nerve cells send im­pulses to each other by means of the fibres at their ends. These fi­bres do not actually touch but are so close to each other that an impulse can travel from one fibre to an­other. Physical agents become stimuli for nerve terminals by transferring energy from the external ^orid to the nerve terminals:

3. Thus all rierve cells connect with each other. There are millions of these connecting nerve cells. Thus a stimulus from any part of the body can reach any other part of it. In the spinal cord and brain, the nerve cells connect with each other by their connecting fibres. Outside the spinal cord and brain, certain long fibres are grouped together forming nerves. Each nerve is made up of thousands of nerve fibres together in a bundle, as a cable is made up of separate wires.

The Brain Centre of the Nervous System

4. We know the nerves to carry impulses to the brain. We know that the brain sends these impulses along so that they go to the right place. The brainjs made up of threqpartsv The cerebrum sits like a cap on the cerebellum. And the medulla is that long portion connecting the brain with the spinal cord. The cerebrum has certain parts that do certain work. Studying human beings with accidental injuries of brains helped scientists to get information about these areas. For instance they have discovered that the part for thought, memory, and feeling is found in the front of the cerebrum. The part for hearing is found at the side of the cerebrum, and the part for sight in the back of the cerebrum.


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