When Louise Brown was born on 25 July 1978, she kicked off an era. The first

游客2023-06-19  10

问题   When Louise Brown was born on 25 July 1978, she kicked off an era. The first    "test tube baby" is a mother  herself now,   and  she’s  been joined  by  millions   of others  born  with  the【C1】________ of in  vitro fertilization (体外受精), or IVF. Now specialists wonder whether people who were conceived by IVF are likely to be【C2】________ .
    "By and large, the kids are just fine. It’s not like the kids having【C3】________  arms or heads," says Carmen Sapienza, a scientist at Temple University. But none is older than their early 30s, and the vast    【C4】________ are under the age of 20, so they haven’t had time for long-term health problems to show up.
    One source of worry is that so many IVF babies have low birth weight. Children-conceived through IVF are more likely to 【C5】________  less than 2.5 kilograms than are babies conceived 【C6】________  . That could spell trouble ahead, because low-birth-weight babies often have long-term health problems. They’re more likely to be obese, to have diabetes (糖尿病) or other problems.
    With that in mind, Sapienza and colleagues have looked at genes that are likely to play a role in such health problems. They found that certain DNA-patterns, which affect how genes are 【C7】________  , are different between IVF and non-IVF children. There’s no way to tell if that’s because of the 【C8】________  used to produce the IVF babies or whether the difference has something to do with the underlying infertility problem the parents had. It’s also 【C9】________  whether these gene-expression differences will translate into health differences. But it does suggest that children conceived by IVF are【C10】________  on some level.
    A)  weigh            E) unclear            I) unique            M) majority
    B)  technology       F) naturally          J) healthy           N) minority
    C)  help             G) expressed          K) explained         O) completely
    D)  unsure           H) procedure          L) extra [br] 【C6】

选项

答案 F

解析 此处应为副词,修饰conceived。此空所在句用more likely…than…表比较,从语义上看,与through IVF(通过体外受精而怀孕)作比较的应该是“自然怀孕”,不难选择naturally。
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