Dangers Await Babies with Altitude

Women who live in the world's highest communities tend to give birth to under-weight babies,a new study suggests. These babies may grow into adults with a high risk of heart disease and strokes.

Research has hinted that newborns in mountain communities are lighter than average. But it wasn't clear whether this is due to reduced oxygen levels at high altitude or because their mothers are under-nourished--many people who live at high altitudes are relatively poor compared with those living lower down.

To find out more, Dino Giussani and his team at Cambridge University studied the records of400 births in Bolivia during 1976 and 1998.The babies were born in both rich and poor areas of two cities: La Paz and Santa Cruz. La Paz is the highest city in the world, at 3.65 kilometers above sea level, while Santa Cruz is much lower, at 0.44 kilometers.

Sure enough, Giussani found that the average birth weight of babies in La Paz was significantly lower than in Santa Cruz. This was true in both high and low-income families. Even babies born to poor families in Santa Cruz were heavier on average than babies born to wealthy families in lofty La Paz. "We were very surprised by this result," says Giussani.

The results suggest that babies born at high altitude are deprived of oxygen before birth. "This may trigger the release or suppression of hormones that regulate growth of the unborn child, "says Giussani.

His team also found that high-altitude babies tended to have relatively larger heads compared with their bodies. This is probably because a fetus starved of oxygen will send oxygenated blood to the brain in preference to rest of the body.

Giussani wants to fred out if such babies have a higher risk of disease in later life. People born in La Paz might be prone to heart trouble in adulthood, for example. Low birth weight is a risk factor for coronary (冠狀的) heart disease. And newborns with ahigh ratio of head size to body weight are often predisposed to high blood pressure and strokes in later life.

41. What does the new study discover?

A. Babies born to wealthy families are heaver.

B. Women living at high altitude tend to give birth to underweight babies.

C. Newborns in cities are lighter than average.

D. Low-altitude babies have a high risk of heart disease in later life.

42. Gussani and his team are sure that

A. babies born in La Paz are on average lighter than in Santa Cruz

B. people living at high altitudes tend to give birth to under-weight babies

C.. the birth weigh of babies born to wealthy families in Santa Cruz

D. mothers in La Paz are commonly under-nourished

43. It can be inferred from what Gussani says in Paragraph 4 that __________ .

A. the finding was unexpected

B. he was very tired

C. the study took longer than expected

D. he was surprised to find low-income families in La Paz

44. The results of the study indicate the reason for the under-wight babies is __________ .

A. lack of certain nutrition

B. poverty of their mother

C. different family backgrounds

D. reduction of oxygen levels

45. It can be learned about from the last paragraph that __________ .

A. high-altitude babies tend to have high blood pressure in later life

B o under-weight babies have a shorter life span

C. babies born to poor families lack hormones before birth

D. new born wealthy families have larger heads compared with their bodies

參考答案：

41.B。細(xì)節(jié)題。題干：新的研究發(fā)現(xiàn)了什么?利用題干關(guān)鍵詞new study可以定位到第一段的第一句，可知“那些生活在世界最高社區(qū)的婦女可能會(huì)生出體重不達(dá)標(biāo)的嬰兒”，所以B(生活在海拔高的地區(qū)的女性可能會(huì)生出體重不達(dá)標(biāo)的嬰兒)為正確答案。

42.A。細(xì)節(jié)題。題干：Gussani和他的團(tuán)隊(duì)確定的是__________ 。利用題干關(guān)鍵詞Gussani and his team和sure可以定位到第四段的首句，可知“足夠確定的是，Gussani發(fā)現(xiàn)La Paz地區(qū)嬰兒出生時(shí)的平均體重與Santa Cruz相比有著顯著的減輕”，所以該題正確答案為A(出生在La Paz的嬰兒比出生在SantaCruz的嬰兒平均體重輕)。.

43.A。細(xì)節(jié)題。題干：根據(jù)第四段Gussani所說(shuō)，可以推斷出__________。利用題干關(guān)鍵詞Gussani says in Paragraph 4可以定位到第四段，從中可知“我們對(duì)這個(gè)結(jié)果感到很吃驚”，所以推知結(jié)果是意料之外的，故該題答案為A(發(fā)現(xiàn)是意料之外的)。

44.D。細(xì)節(jié)題。題干：研究結(jié)果表明造成嬰兒體重不達(dá)標(biāo)的原因是__________。利用題干關(guān)鍵詞result ofthe study和reason等可以定位到第五段，可知“研究結(jié)果表明出生在高緯度的嬰兒在出生前被剝奪了氧氣(呼吸較少的氧氣)”，由此不難得出該題的答案為D(氧氣的減少)。

45.B。推斷題。題干：根據(jù)最后一段可以推斷出__________。根據(jù)最后一段，可知La Paz地區(qū)出生的孩子在成年時(shí)有患心臟病的風(fēng)險(xiǎn)，體重不達(dá)標(biāo)是患冠心病的一個(gè)因素，新出生的頭比身子大的孩子在今后的生活中可能會(huì)有患高血壓和中風(fēng)的風(fēng)險(xiǎn)。由此可知選項(xiàng)A與原文不一致，選項(xiàng)C未提及，選項(xiàng)D未提及，因此可以推斷這些孩子因?yàn)榛疾「怕瘦^大而壽命不太長(zhǎng)，故該題答案為B.(體重不達(dá)標(biāo)的嬰兒壽命比較短)。