Question

Babies born in summer are more likely to become short-sighted in late life, a study has shown.

As many as a quarter of all cases of short-sightedness are caused by too great an exposure to sunlight in the first weeks of life, say eye experts.

They are advising all parents to put sunglasses on their babies during the first weeks.

Scientists had already established that over-exposure to sunlight caused shortsightedness in animals.

Researchers who compared the months in which babies were born with whether they needed glasses later on say the principle also applies to humans.

A study of almost 300,000 young adults-the largest of its kind-showed that those born in June and July had a 25 per cent greater chance of becoming severely short-sighted than those born in December or January.

Research leader Professor Michael Belkin, of Tel Aviv University, said it was because prolonged illumination(光照) causes the eyeball to lengthen-causing short-sightedness.

Hence the more light a newborn is exposed to, the more the eyeball lengthens and the worse the short-sightedness will be.

The mechanism which lengthens the eyeball is associated with levels of melatonin(褪黑激素), a pigment (色素) which protects the skin against harmful rays of the sun.

In young babies not enough melatonin is released as protection, meaning they are more vulnerable to sunburn and changes to eyeball shape.

Sight expert Professor Daniel O’Leary, of Anglia Ruskin University in Cambridge, said “At the moment we don’t know the precise cause of why light exposure affects sight, but the evidence seems to prove that it is one of the reasons for people becoming shortsighted.”

1.Babies born in summer are more likely to be shortsighted ____________.

A. because the summer sun is too strong for babies

B. because babies born in summer have lengthened eyeballs

C. if they are exposed too much sunlight in the first weeks after they are born

D. if parents don’t know a proper way to protect their babies’ eyes

2.Melatonin is a kind of material to ___________.

A. prevent the eyes from becoming near-sighted

B. protect the skin from harmful sun rays

C. make our body strong

D. protect babies’ eyes from summer sun

3.From what Professor Daniel O’Leary says we can conclude that ___________.

A. there is no evidence that shortsightedness is related to exposure to sunlight

B. whether light exposure affects sight still needs to be further proved

C. he believes that light exposure can cause shortsightedness

D. he tries to give the cause of why light exposure affects sight

4.The underlined word “vulnerable” in the passage probably means __________.

A. easy to be harmed B. resistant

C. protective D. changeable

Answer 1

1.C

2.B

3.C

4.A

【解析】

试题解析：研究表明在夏季出生的婴儿长大后更容易成为近视眼，眼科专家称多达四分之一的近视眼病例是由于在出生后前几周里暴露阳光太久造成。

1.小题1】细节理解题。根据第一段和第二段得知，眼科专家称：在夏季出生的婴儿长大后更容易成为近视眼，因为由于婴儿在出生后前几周里暴露阳光太久造成。故选C 。

2.小题2】推理判断题。根据倒数第三段The mechanism which lengthens the eyeball is associated with levels of melatonin(褪黑激素), a pigment (色素) which protects the skin against harmful rays of the sun.得知，褪黑激素是一种可以保护皮肤不受阳光紫外线伤害的色素。故选B 。

3.小题3】推理判断题。根据最后一段得知，剑桥大学的视学专家Daniel O’Leary教授相信暴露在阳光下会导致人们近视眼。故选C。

4.小题4】猜测词义题。在婴幼儿时期，没有产生足够的褪黑激素作为保护，婴幼儿更容易被阳光灼伤，并且改变眼球的形状。故选A。

考点：科研类文章