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Tiêu đề Hormones and the endocrine system
Chuyên ngành Biology
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Some proponents of HAT have igi their enthusiasm 0 the face of this new evidence, fecammending it only to patients whose symptoms interfere with their-abifities to live norrnallives: a

Trang 1

closest in meaning to thought to control aif communication within tie body and the resulting

integration of behavior Scientists had determined that nerves ran,

(B) surprised digestion However, experiments by William Bayliss and Emest Starling

(C) invented on tha chemical secretin, which is produced in the small intestine when

D) ‘vated ood enters thie stomach, eventually challenged that view Feom the small

( motivate inlestina serrdfin traels (hro0gh lhe bloodstream lo the panoroas, The, Š

stimulatas the release ct digestive chemicals, ln this fashion, the|Intestinal culls that produce secretin ultimately requiate the production of differant chemicals int a different organ, the pancreas

Suctra coordination of processes had besn thought to require cantrat

by the nervous system; Bayliss and Starling showed that it could occur through chemicals alone This discovery BI] Siarlinrj to-cain-the farm hømmöne to Teler to secretin, taking it from the Greek word homen, meaning “tovaxcite” or “to set in motion.” A-hormorie isa chemical’

produced by oneitissue to make:things happen elsewhere,

‘Asmore hormanes.were discovered, they were categorized, printarily according te the proses by which they aperaied on the body Some glands (which maka up the endocrine system) secrete hormones ditectly into the bloodstream Such glands include the thyroidand the pituitary The exocrine system consists of organs and glands that produce substances thatare used outside the bloodstream, primarily for digestion The pancreas

js che such organ, although Itsecretes same chemizals inta the blood and thus Is-also part of the endocrine system

Much has been jeamed about honmones since their discavery, Same play suơh gu in xa bodily 0065583 0ƒ behavior that their St

BEE: Hormonal systems ara vary intricate, armours al he ght chemicals can suppress appetite, calm aggtessicn, and change the altitude ofa parent toward a'child, Cestain hormones accelerate the deyelupment of the body; regulating growth and form; others may oven define an individual's personality characteristics

The quanitiles and proportions of hermanes producad change with age, 0 sclentist: hawn given a presi deal of study te chifts

In the endocrine system ewer time in the hopes a! alleviating aliments eseoctated with agiag

In fact some tormans therapies are already Very common mt A pamblnation of esirogen and progestercne hee been proscribed for decades io women win wast fe reduca myod gwings, : 3 sudden eltangss In boy tạrngoralur9, and affiet tise0inÏpris

" the treatment was also believed io: prevent weakening of the bores, ml At

least one.siudy has linked HAT wilh a heightened risk of heart disease and certain types of cancer RAT may alsa increage the likelihood thal

bloodstream snd hiack major bieed vessaie—eill form Some

proponents of HAT have (igi their enthusiasm (0 the face of this new

evidence, fecammending it only to patients whose symptoms interfere with their-abifities to live norrnallives: a

Human growih hormone may also be given to patients who are secreting

affects growth hormone haz on the body, euch treatments are yenerally reviricied to children who would be pathologleally email [ny stature without It, Growth hormone alfects not just physical

$iza tat aise the digestion of food and the aging process Researchers and family physicians lend to agree that it is foolhardy ta dispense it in cases in which the risks -are not clearly outweighed hy the benefits

THE PRINCETON REVIEW TOEFL i8T PRACTICE TEST Ml 405

Trang 2

30 To be considered a hormone, a

chemical produced in the body must

process

(B) influence the operations of

the nervous system

different part of the body

behavior

Hormones in the Body

Up to the beginning of the twentieth century, the nervous system was thought to control all communication within the body and the resulting integration of behavior, Scientists had determined that nerves ran, essentially, on electrical impulses These impulses were thought to be the for thought, emotion, movement, and internal processes such as digestion However, experiments by William Bayliss and Ernest Starling

on the chemical secretin, which is produced in the small intestine when food enters the stomach, eventually challenged that view From the small intestine, secretin travels through the bloodstream to the pancreas There, it stimulates the release of digestive chemicals In this fashion, the intestinal cefls that produice secretin ultimately regulate the production of different chemicals in a differeni organ, the pancreas

Such a coordination of processes had been thought to require control

by the nervous system; Bayliss and Starling showed that it could occur through chemicals alone, This discovery :

term hormone to refer to secretin, taking it from the Greek word Aormon, meaning “to excite” or “to set in motion.” A hormone is a chemical produced by one tissue to make things happen elsewhere

As more hormones were discovered, they were categorized, primarily according to the process by which they operated on the body Some glands (which make up the endocrine system) secrete hormones directly into the bloodstream Such glands include the thyroid and the pituitary The exocrine system consists of organs and glands that produce substances that are used outside the bloodstream, primarily for digestion The pancreas is one such organ, although it secretes some chemicals into the blood and thus is also part of the endocrine system

Much has been learned about hormones since their discovery Some play

sses of behavior that th irabsence

aggression, and change the attitude of a parent toward a child Certain hormones accelerate the development of the body, regulating growth and form; others may even define an individual's personality characteristics, The quantities and proportions of harmones produced change with age, so scientists have given a great deal of study fo shifts

in the endocrine system over time in the hopes of alleviating ailments associated with aging

In fact, Some hormone therapies are already very common mA combination of estrogen and progesterone has been prescribed for decades to women who want io reduce mood swings, sudden changes in body temperature, and other discomforts caused by lower natural levels of these hormones as they enter middle age m@ Known as hormone replacement therapy (HRT), the treatment was also believed to prevent weakening of the bones m At least one study has linked HRT with a heightened risk of heart disease and certain types of cancer HAT may also increase the Hkelihood thal blood clots—dangerous because they could travel through the bloodstream and block major blood vessels—wiil form Some proponents of HRT have igaapered their enthusiasm in the face of this new evidence, recommending it ‘only ‘to patients whose symptoms interfere with their abilities to live normal lives, i

Human growth hormone may also be given to patients who are secreting abnormally low amounts on their own Because of the complicated effects growth hormone has on the body, such treatments are generally restricted to children who would be pathologically small in stature without it Growth hormone affects not just physical size but also the digestion of food and the aging process Researchers and family physicians tend to agree that it is foolhardy to dispense it in cases in which the risks are nat clearly outweighed by the benefits

406 MM CRACKING THE TOEFL

Trang 3

Rea

31 The glands and organs mentioned

in paragraph 3 are categorized

according to

understand their function

hormones into the body

secrete influence the aging process

chemicals into the blood

Paragraph 3 is marked with an arrow

[>]

Hormones In tha Body

Up'te the beginning of the twentieth century, the nervous system was

theught to cantrol all communication wilhin the body and the resulting integration at behavior Scientists hai determined that neryes (an, essentially, on electrical impulses These impulses were thought to be-tie

6008 for thought, emotion, mavement, and internal processes such as digestion, However, experiments by William Bayliss and Emest Starling

on the chemical Seorstin,.wiiich iS produced inthe small intestine when

tood enters the stomach, eventually challenged that view From the small —

intestine, secrefin travels through the bloodstream ta the pancreas, There, if

stimulates fhe release iif digeshve chemicals In this fashion, the intestinal calls that produce seotétin ullircately regulate the production.of diferent chemicals in 3 different organ, the pancreas,

Such a coordination ot processes had been thought te require control

by the Nervous system) Bayliss and Starling showed litat it could occur

thigugh chemicals-alona Thì discovery #f3Sf Slarlìnu to coin, the

term fornone to refer (o secretin, taking it rom the Greek word hormer, meaning “to éxcile” or“to set in motion.” A hormone Is 2 chemical produced by one tissue lo make things happen elsewhere

As mare hoymanes were discovered, they were categurized, primarily according to lhe process by which they: operated on the body; Some glands (which make-up the endocrine system) secrete hormones dinettly inta the bloodstream.-Such glands include the Thyraid’and the pituitary The tefiiIE &ysföim consists of organsard glands thal produce substances {fal are used outside the bloodstream, primariiy for digestion The pancreas is one such organ, alifiough it secreigs same chemicals into the dindd and thus is aise part of the endocrine system

Much has been learned about hormones since thei discovery; Some play Such Hl roles in regulating body pracesses:of behavior that their absence

git

aggression, and change the altitude of a oxent toward a oh, Carian hormones accelerate the development of the body, regulaling grawih and form, olhers may even’define an individual's personality chacacteristics

The quantities and proportions of hormones produced change with age, se scloniists have piven a graat deal of study to shifis

in the andocring system overtime inthe hopes af alleviating aliments associaiod with aging

Infact, some hormone Iherapies are already: very.commoan ial: A combination of astrogen and progesterons hax been prescried for devades fo women who wan to reduce mood swings, sudden changes in bady temperatura, and other diecamioris caused by lower natural lovels of thore hormones az they ater middte age & Known as hormone replacement therapy (HRT), Ihe:treatment was:aiso believed fo prevent weakening of the bangs, @ At least one study: has linked HRT with a heightened tisk of heart disease and, certain types of cancer, HAT may alse tnereaga the likelihood that hieod clots—dangeroas bacausa they could travel through Iho bloodstream and black jor blood vessals—will farm Some proponents of HAT have (ii

evidence, recommending it nnly te patients whose symptoms interfere with [hei abilities to'live normal lives

Hurrian growth Hommonemay aso bé-giver ta patients who are-secrating abnormally lowamounts on theirown, Because of the complicated effects growth hormone has on the body, cuch (reatments are generally restricted to children win would he pathologically small In-stature without If Growth hormone affects not just physical size-but also the digestinn of food and the aging process: Researchers and family physicians tend to agree that it ìs löolhardy to dispense it in cases in which the risks-are not clearly oulweighed by tia benefits

THE PRINCETON REVIEW TOEFL iBT PRACTICE TEST MB 407

Trang 4

J8)

closest in meaning to

(C) significant

(D) simple

Hormones in the Body

Up to the beginning of the twentieth century, the nervous system was thought to control-all communication within the body and the resulting integration of behavior Scientists fad determined that nerves ran, essentially, on electrical impulses, These impulses were thought to be the ÿfiBf§š lor thought, emotion, movement, and internal processes such as digestion However, experiments by William Bayliss and Emest Starling

on the chemical secretin, which is produced in the small intestine when food enters the stomach, eventually challenged that view From the small intestine, secretin travels through the bloodstream ta the pancreas

There, ¥ stimulates the release of digestive chemicals In this fashion, the intestinal cells that produce secretin ultimately regulate the production of different chemicals in-a different organ, the pancreas

Such a coordination of processes had been thought to require control -

by the nervous system; Bayliss and Starling showed that it could occur through chemicals atone This discovery Speed Starling to coin the term hormone to refer to secretin, taking it from the Greek word hormen, meaning “to excite” or “to set in motion.” A hormone is a chemical produced by one tissue to make things happen elsewhere

As more Hormones were discovered, they were categorized, primarily according to the process by which they operated on the body Some glands (which make up the endocrine system) secrete hormones directly into the bloodstream Such glands include the thyroid and the pituitary The exocrine system consists of organs and glands that produce substances that are used outside the bloadstream, primarily for digestion The pancreas is one such organ, although it secretes same chemicals into the blood and thus is also part of the endocrine system,

Much has been learned about hormones since their discovery Some play such fy roles in regulating bodily processes or behavior that their absence would cause immediate death 0fftonbt

lormonal systems are very intricate Eve : amounts af the right chemicals can suppress appetite, calm aggression, and change the attitude of a parent toward a child Certain hormones accelerate the development of the body, regulating growth and form; others may even define an individual's personality characteristics The quantities and proportions of hormones produced change with aye, so scientists have given a great deal of study to shifts in the endocrine system over time in the hopes of alleviating ailments associated with aging

In fact, some hormone therapies are already very common i A combination of estrogen and progesterone haa been prescribed for decades to women who want to reduce mood swings, sudden changes in body temperature, and other discomforts caused by lower natural levels of those hormones as they enter middle age, @ Known as hormone replacement therapy (HRT), the treatment was also believed to prevent weakening of the bones: @ At least one study has linked HRT with a heightened risk of heart disease and certain types of cancer HRT may aiso increase the likelihood that blood ciots—dangerous because they could travel through the bloodstream and block major blood vessels—eill form Some proponents of HRT have ƒ their enthusiasm in the face of this new evidence, recommending it only to patients whose symptoms interfere with their abilities to live normal lives a

Human growth hormone may also be given lo patients who are secreting abnormally low amounts on their own Because of the complicated effects growth hormone has on the body, such treatments are generally restricted to children who would be pathologically small in stature without it Growth hormone affects not just physical size but also the digestion of food and the aging process Researchers and family physicians tend to agree that it is foolhardy to dispense it in cases

in which the risks are not'clearly outweighed by the benefits:

408 MM CRACKING THE TOEFL

Trang 5

+7 ati Up tothe beginning.af the twentieth century, Ihe nervous system wes., closest in meani ng tọ fought to contro! all communication within the bady and the resulting

integration of bshavior Sclentisis had determined that nerves rar,

<n W985 lúr thought, emotion, movernent, 20 inlarnal processes such as

(C) changing on thechemical seoretin, which ts produced in the:small intestine when =

stimulates the release.of digestive chemicals: Ih this fashion, the: intestinal cells thal produce secretin ullimatety regulate the praduction of different chemicalS int a diffrent organ, the pancreas

Suely’a coordination of processes had beer thought to require control

tftrough chemicalsalone This discovery (ER Starling to coin the farm formoneto refer to secretin, taking it from the Greek word hommon, meaning “to excite’ ar “fo set in mation.” A harmans is.4 chemical

produced by one Tissue to make things happen elsawhere

As more hormones were discovered, lhey were valagorized, primarily:

according ti Ihe progess by-which they operated on the body Some glands (which make up the endocrine system) secrete hormanes directly into”

the bicodstteam Such glands include the (hyroid and the pituitary The excorine system consists af organs and lands that produce ‘substances:

that are-used outside Ihe, bloodstream, primarily for digestion The pancreas |S ofle such organ, although it seeretes some chemicals into the hlood-and thus: is-alsn part af the endocrine system

Much Has been learned about hormones'sines theirdiscavery Some play

‘suctr fi roles in regulating bodily processes or behavior that their absence

would cause imgnediate death :

B amounts of the night chemicals: car-suppress appetite, calm aggression, and change the attitude of a parent toward a child: Certain hormones accelerate ihe development of the body, requiating growth and form; others: may even define-an individual's personality characteristics

with age; 0 sclantisie have given a great.deal of study to sRifc

In the endocrine syciem over time in the hopes of allaviailing aliments assactated with aging

Infact, some hormone therapies are already very common, a A combination at sztrogen and progesterone has been prescribed

for decades lo women who want to reduge mood swings, sudden chanpes In body temporaturs, and othar discomtorts

caused by lower natural lewais of these hormones as they enfer middle age @ Knowr as hormene replacement therapy (HAT), the trediment'was also believed to prevent weakening: of the bones, i At least one:studly has’ linked HAT with heightened fist oi heart disease and certain types of carioes, HRT may also increases the likelihood that blood cloiz—dangarous because they could travel through the

proponents of HAT haves their enthusiasm in the face of this new evidenoe, recommending itonfy to patients whose symptoms interfare with their-abilities lo fivenormal lives;

Human growth hormone may alsa he given to patients who.are secreting abnormally iow amaunis.on thelr own Because ot the compliratad

- gensrally rasiri¢ted to children who would ha pathologically

: mall in stature without it Growth hormone affects not just physical

family physicians tend to agree that it |s foolhardy to dispense thin cases in which the risks are net clearly outweighed by the benefits,

THE PRINCETON REVIEW TOEFL iBT PRACTICE TEST Ml 409

Trang 6

34 Which of the sentences below best

expresses the essential information

in the highlighted sentence in the

passage? /ncorrect answer choices

change the meaning in important

ways or leave out essential

information

(A) Most moods and actions

are not voluntary because they are actually produced

by the production of hormones in the body

(B) Because the effects of

hormones are difficult to

measure, scientists remain unsure how far-reaching their effects on moods and

actions are

producing enough hormones, urgent treatment may be necessary to avoid psychological damage

hormones is not easy

to measure, but they can affect both people's

psychology and actions extensively

Hormones In the Body

Up to the beginning of the twentieth century, the nervous system was thought to control all communication within the body and the resulting integration of behavior Scientists had determined that nerves ran, essentially, on electrical impulses These impulses were thought to be the

@ for thought, emotion, movement, and internal processes such as digestion However, experiments by William Bayliss and Emest Starling

on the chemical secretin, which is produced in the small intestine when food enters the stomach, eventually challenged that view From the small intestine, secretin travels through the bloodstream to the pancreas, There, it stimulates the release of digestive chemicals In this fashion, the intestinal cells that produce secretin ultimately regulate the production of different chemicals in a different organ, the pancreas

Such a coordination of processes had been thought to require control”

by the nervous system; Bayliss and Starling showed that it could occur through chemicals alone This discovery § | Starling to coin the term hormone to refer to secretin, taking it from the Greek word fhormon, meaning “to excite” or “to set in motion.” A hormone is a chemical produced by one tissue to make things happen elsewhere

As more hormones were discovered, they were categorized, primarily according to the process by which they operated on the body, Some glands (which make up the endocrine system) secrete hormones directly into the bloodstream Such glands include the thyroid and the pituitary, The exocrine system consists of organs and glands that produce substances that are used outside the bloodstream, primarily for digestion The pancreas is one such organ, although it secretes some chemicals into the blood and thus is-also part of the endocrine system

Much has been learned about hormones since their discovery Some play such ie roles in regulating bodily processes of behavior that thei abse ce would catise immediate death

Even amounts of the right chemicals can suppress appetite, calm aggression, and change the attitude of a parent toward a child Certain hormones accelerate the development of the body, regulating growth and form: others may even detine an individual's personality characteristics

The quanilties and proportions of hormones produced change with age, so sciantists have given a great daal of study to shifts

in the endocrine system over time In the hopss of alleviating aliments associated with aging

in fact, some hormone therapies are already very common, mA combination of estrogen and progesterone has been prescribed for dacades to women who wani to reduce mood swings, sudden changes in body temperature, and other discomforts caused by lower natural fevels of those hormones as they snter middle age @ Known as hormone replacement therapy (HRT), the treatment was also believed to prevent weakening of fhe bones At least one study has linked HAT with a heightened risk of heart disease and certain types of cancer HRT may also Increase the likelihood that blood clots—dangerous because they could travel through tha bloodstream and block major bicod vesseis—will form Some proponents of HRT have id their enthusiasm in the face of this new evidence, recommendin tonly to patients whose symptoms interfere with their abilities to five normal lives

Human growth hormone may alsa be given to patients who are secreting abnormally tow amounts on their own Because of the complicated effects growth hormone has on the body, such treatments are generally restricted to children who would ba pathologically small in stature without it Growth hormone affects not just physical size but also the digestion of food and the aging process Researchers and family physicians tend to agree that it is foothardy to dispense it in cases in which the risks are not clearly outweighed by the benetits

410 Mi CRACKING THE TOEFL

Trang 7

Bet

The Word š in the passage is

closest in meaning to

(A)

(B)

(C)

(D)

decreased advertised

prescribed researched

‘essentially, on electrical imputses; Thase impulses were thougnt to be the

‘Such a Chordinalion af processes Rad been ihought to require canirol

Honrmenes ii the Body Upto the beginning of the twentieth century, thie:narvous.system was

thowghtt to control all communication wilhin the body and the resulting integration of behavier Scientists had determined that nerves ran,

ae for thought, emotion, mavement, and intemal processes such: as digestion However, experimends by: William Bayliss ara Emest Starling

on the chemical secretin, which is produced inthe small intestine wher;

food enters the stomach, eventually challenged that: view From the small

intestine, Setretin travels through the bloodstream to the pancreas There, if

stimulates the selease of digestive chemicals, In (his fashion, the intestinal cells-hat produce secrefin ultimately regulate the production ofdifi¢rent chemicalsin 2 different organ, the pancreas

by Ihe nervous aystem: Bayliss-and Starling stowed that.it could oceur through chemicals alone This discovery Sigil Starling to coin the tem ‘hormoneto reler to:sestetiny, taking it from the Greek word Harman, meaning: “it excite” or “to sel in motion.” A‘hormorie isa chemical produned by’one tissve-to:make things happerr elsewhere

AS more hormones: were discovered, they ware-calegorized, primarily according ta tha-pracess by which they operated an the body Some glands (which make up Ihe endocrine system) secrete hormones: directly into the-bloodstteam Such glands include the thyrold and the pituilary The:

exonrine system consists.af organs:and glaridé that produce:substances that are used cutside lhe bloodstream, primarily for digestion The pancreas |S ané-such organ, although ifsecretes:some,chamicals into the:

blood-and thus also part of the endocrine system

Much fias been learned about hermanes:since theirdiscavery: Some play such kag roles in regulating bodily processes ar behavior that'thetr absence would cause immediate death ©

AQTESSION, “and change Ihe aitiude ofa parent cid a child Certain

hormones apcelerate the develonment of jije bady, regulating growth and form: olhers may even deline.an individual's personalily characteristics

The quantities-and propariions of hormones praducad change with age, so scluntizis have given 9 great deal of stuiy to phi

In the endosring zystem over Hime in the hopes of allewiating ailments associated with aging

Ini fact, some hormone therapies are already very common A combination of astrapan and progesiarone has heen prescribed foridecades to woman who want ty reduce mond swings;

sudden changes In body temnperatore, and other discamiorts caueod hy lower natural levels of those hormones az they éotar middle age, Known as hormone féplacement therapy (HRT), the treatment was‘also:balieved:te prevent weakening of the bones: EM At least one: study has'linked HRT witha heightened risk of heart disease-and certain.types of cance, HAT may alsa Incraase the ikellhood thal hood clots—dangerous becauss they could travel through the

blondstraam and Klock major blood veszals—will form, Some

proponents of HRT have Wiejigugad their enthusiasm in the face of this new avidencs, recommending itonly.to patients whase symptoms interfere witht their abilities To live normal (ives: mi

Human growth hormone may also be givento patients:who are secreting abnormally Jow amotinis on their own Berause of tha complicated effects growth hormone has-on the hody, such treatments are penerally restricted fo childien who would be pathologically small in stature without f Growitr hormone aifeats nat just physical size but also the digestion of tood-and.the aging process, Rasearchers:and family physicians tend to agreé:that (tis foalhsrdy to dispense it in cases in which therrisks are not clearly outweighed by the benstits

THE PRINCETON REVIEW TOEFL iBT PRACTICE TEST Mi 411

Trang 8

36 Which patients are usually treated

with growth hormone?

(A) Adults of smaller stature

than normal

systems

(C) Children who are not at risk

from the treatment (D) Children who may remain

abnormally small

Hormonas:in the Body

Up to the beginning of the twentieth century, ihe nervous system was thought to control ail communication within the body and the resulting integration of behavior Scientists had determined that nerves ran, essentially, on electrical impulses These impulses were thought to be the G92 for thought, emotion, movement, and internal processes such as digestion However, experiments by William Bayliss and Ernest Starling

on the chemical secretin, which is producad in the small intestine when food enters the stomach, eventually challenged that view From the small intestine, secretin travels through the bloodstream to the pancreas There, lŸ stimulates the release of digestive chemicals In this fashion, the intestinal cells that produce secretin ultimately regulate the production of different chemicals in a'different organ, the pancreas

Such a coordination of processes had been thought to require control -

by the nervous system; Bayliss and Starling showed that it could occur through chemicals alone, This discovery

term hormone to refer to secretin, taking it from the Greek word harmon, meaning, “to excite” or “to set in motion.” A hormone is a chemical produced by one tissue to make things happen elsewhere

As more hormones were discovered, they were categorized, primarily according to the process by which they operated on the body Some glands (which make up the endocrine system) secrete hormones directly into the bloodstream Such glands include the thyroid and the pituitary The exocrine system consists af organs and glands that produce substances that are used outside the bioadstream, primarily for digestion The pancreas is one such organ, although it secretes some chemicals into the blood-and thus is also part of the endocrine system

Much has been learned about hormones since their discovery Some play such key roles in regulating bodily processes or behavi

would cause immediate death

ys ly Eve amounts of the right chemicals can suppress appetite, calm aggression, and change the attitude of a parent toward a child Certain hormones accelerate the development of the body, regulating growth and form; others may even define an individual's personality characteristics, The quantities and proportions of hormones produced change with age, so scientists have given a great deal of study to shifts

in the endocrine system over tims in the hopes of alleviating ailments associated with aging

In fact, some hormone therapies are already very common @ A combination of estrogen and progesterone has been prescribed for decades to women who want to reduce mood swings, sudden changes In body temperature, and other discomforts caused by lower natural levels of those hormones as they eater middle age m@ Known as hormone replacement therapy (HRT), the treatment was also believed to prevent weakening of the bones, a At least one study has linked HRT with a heightened risk of heart disease and certain types of cancer HRT may also increase the likelihood that blood clots—dangerous because they could travel through the bloodstream and block jor biood vessels—wili form Some proponents of HRT have § their enthusiasm in the face of this new evidence, recommending it only to patients whose symptoms interfere with their abilities to live normal lives

Human growth hormone may also be given to patients who are secreting abnormally low amounts on their own Beeausa of the complicated effects growth hormane has on the body, such treatments are generally restricted to children who would be pathologically smaii in stature without it Growth hormone affects not just physical size but also the digestion of food and the aging process, Researchers and family physicians tend to agree that it is foolhardy to dispense it in cases in which the risks are not clearly outweighed by the benefits

412 ME CRACKING THE TOEFL

Trang 9

d0

37 Click on the highlighted sentence

(in bold text in the passage and

repeated below) in the passage

where the author explains

the primary goal of hormone

replacement therapy

(A)

(B)

(D)

The quantities and proportions of hormones produced change with age,

so scientists have given a great deal of study to shifts

in the endocrine system over time in the hopes

of alleviating ailments associated with aging

A combination of estrogen

and progesterone has been prescribed for decades

to women who want to

reduce mood swings, sudden changes in body temperature, and other discomforts caused by lower natural levels of those hormones as they enter middle age

HRT may also increase the likelihood that blaed clots—dangerous because they could travel through the bloodstream and block major blood vessels—will form

Because of the complicated

effects growth hormone

has on the body, such

treatments are generally restricted to children who would be pathologically

Honnones inthe Body Upto the:beginning af the twentieth century, the rervous.sysiem was fhoupiit to conted! ail communication within the body and the resulting integration of behavior Scientists fad determined that nerves ran, essentially, on cecil impulses, These impulses were thought to be the digestion Hats experiments by Witltam Bayliss and Emiest Starling

on the ehernical secretin, which ts produced in the:smail intestine when food enters tfie stomach, eventually challenged that view From the sinall intestine, secretin travels through the bloodstream to:the pancreas There, # Stimulates the release ot digestive chemicals In this fashion, the intestinal calls that produce secretin ultimaiely regulate the production of different chemicals in 2 different erqan, the pancreas

Sunk a coordination of processes had been thoupht'to require sontral

hy lhe:nervous system; Bayliss and’ Starling showed that it could occur firough chemicals alone This discovery lille Starting towoin the term Forman to reter to-searelin, takingy it trom the Greekoword! Aanmon;

meaning “to excite” of “torset | motion.” A-harmone is achemical produced hy one tissue lo make things happen elsewhere

AS more hormones were discovered, they were: categorized primarily according tuthe process by which Ihey operated onthe body Some glands | {which make-up the endocrine syste) secrete hormones directly into the bloodstream, Such glands include the thyroid and the-nttuitary: The:

exocrine system consists:of nrgans and glands that praduce: substances that are used outside the: bloodstream, primarily for digestion The pancreas: |

is one such organ; although itsecretes some chemicals inta.the- blood and Thus [s aiso part of the endperins svslam,

Muich has been leamed about harmones:since theif discovery, Some play, | such ji roles in regulating bodily processes or behavior that thelr pee

‘immediate death

andl change the afittude of @ parent toward @ child Certain hormones accelerate tire tlevelopment of the bady; regulating growth and form; others may even define an individual's personality charactersstics, The quantities and proporilona of hormones produced change Ƒ with age, s0 ecientists have given agraeidoal of study to shlits ƒ

in the endocrine system over Dime in the hopes af alleviating allments scsociated with aging

In facl, some harmione therapies are already very comma a A combination of agtroyen and progesigrone hag been prascrived | far tecadas to women wie want fo reduce mood swligs,:

suddan changes in body fompersiura, and athay discamforts

cousad hy lower natural Ioveis of these hormones ax thay

poter middie'age m@ Known as homone replacement therapy (HAT), the treatment Was also belisved ta prevent weakening of the bones, Mt At Isast one study has linked HAT wittia heightened risk of Neart disease and certain types of caricer HAT may alte Increase the Ilkalihood that hiood ciots—dangerous because thoy could travel throagh the bleodstream and blogk major blond vateels—will form Some

eee theit enthusiasm in the face of this new evidence, recommending it only to patients whose symptoms interfere with [ their abilities to live-tiormal fives, a

human arowth hormone may also be given to patients: who are-secreting

abnormally law amaunts'‘on thels own Because of the complicated

Bitetts griwth hormones has oo the body, such trasiments are generally restricted to children who would be pathologically small in stature without it Grewih hormone affects not just physical size but also the digestion of tood and the aging prosess Researchersand |

family physibians tend'to agree thal itis foolhardy ta dispense it in eases in

which the:risks are nobclearly oulweighed by the benefits,

THE PRINCETON REVIEW TOEFL iBT PRACTICE TEST MM 413

Trang 10

38 Look at the four squares [] that

indicate where the following sentence

could be added to the passage

The body is a complex machine,

however, and recent studies have

called into question the wisdom of

essentially trying to fool itssystems

into believing they aren't aging

Where would the sentence best fit?

Click on a square [] to add the

sentence to the passage

[Here, on this practice test, circle your

answer below.|

(B) Square 2

(C) Square 3

(D) Square 4

Hormones in tha Body

Up to the beginning of the twentieth century, the nervous system was thought to contro} all communication within the body and the resulting integration of behavior Scientists had determined that nerves ran, essentiaily, on electrical impulses These impulses were thought to be the

#2@98 for thought, emotion, movement, and Internal processes such as digestion However, experiments by William Bayliss and Ernest Starling

on the chemical secretin, which is produced in the small intestine when food enters the stomach, eventually challenged that view From the small intestine, secretin travels through the bloodstream to the pancreas There, &

stimulates the release of digestive chemicals In this fashion, the intestinal cells that produce secretin ultimately regulate the production of different chemicals in'a different organ, the pancreas

Such a coordination of processes had been thought to require controt

by the nervous system; Bayliss and Starling showed that it could occur through chemicals alone This discovery Settee

term hormone to refer to secretin, taking it from the Greek word ñØ/mon, meaning “to excite” or “to set in motion.” A hormone is a chemical produced by one tissue to make things happen elsewhere

As.more hormones were discovered, they were categorized, primarily according to the process by which they operated on the body Some glands (which make up the endocrine system) secrete hormones directly into the bloodstream Such glands include the thyroid and the pituitary, The exocrine system consists of organs and glands that produce substances that are used outside the bloodstream, primarily for digestion The pancreas

is one such organ, although it secretes some chemicals into the blood and thus is also part of the endocrine system

Much has been learned about hormones since their discovery Some play such key roles in regulating bodi ior that their absence

would cause immediate death :

i, Hormonal systems are very intricate

t chemicals can suppress:appetite; calm aggression, and change the attitude of a parent toward a child Certain hormones accelerate the development of the body, regulating growth and form; others may even define an individual's personality characteristics

The quantities and proportions of hormones produced change with age, so scientists have given a great deal of study to shifts

in the endocrine system over time in the hopes of alleviating allments associated with aging

In fact, some hormone therapies are already very common i A combination ot estrogen and progesterone has been prescribed for decades to women who wani to reduce mood swings, sudden changes in body temperature, and other discomforts caused hy lower natural iavels of those hormones as they enter middle age @ Known as hormone replacement therapy (HRT), the treatment was also believed to prevent weakening of the bones m At least one study has linked HRT with a heightened risk of heart disease and certain types of cancer HAT may also Increase the likelihood that blood clots—dangerous because they could travel through the hloadstream and biock blood vessels—will form Some proponents of HRT have j& their enthusiasm in the face of this new evidence, recommending it only to patients whose symptoms interfere with their abilities to live normaltives, IE

Human growth hormone may also be given to patients who are secreting abnormally low amounts on their own Besause of the coraplicated effects growth hormane has on the body, such treatments are generally restricted to children wha would be pathologically small in stature without It Growth hormone affects not just physical size but also the digestion of food and the aging process Researchers and family physicians tend to agree that it is foolhardy to dispense il in cases in which the risks are not clearly outweighed by the benefits

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