FeiFei-46求教-->babypace转移

justdo665

46. Twelve healthy volunteers with the Apo-A-IV-1 gene and twelve healthy volunteers who instead have the Apo-A-IV-2 gene each consumed a standard diet supplemented daily by a high-cholesterol food. A high level of cholesterol in the blood is associated with an increased risk of heart disease. After three weeks, the blood cholesterol levels of the subjects in the second group were unchanged, whereas the blood cholesterol levels of those with the Apo-A-IV-1 gene rose 20 percent.

Which one of the following is most strongly supported by the information above?

A.      Approximately half the population carries a gene that lowers cholesterol levels.

B.      Most of those at risk of heart disease may be able to reduce their risk by adopting a low-cholesterol diet.

C.      The bodies of those who have the Apo-A-IV-2 gene excrete cholesterol when blood cholesterol reaches a certain level.

D.      The presence of the Apo-A-IV-1 gene seems to indicate that a person has a lower risk of heart disease.

E.       The presence of the Apo-A-IV-2 gene may inhibit the elevation of blood cholesterol.

此题选E我不反对，但为什么C不对呢？既然，bodies已经 excrete cholesterol ，那么，其blood cholesterol levels自然是不变了！

arundhati

也许你对C的理解有些出入。C的意思是说体内含有A2基因的人的身体在血液里的胆固醇达到一定程度时会分泌胆固醇。

人体在什么程度下分泌胆固醇属于无关信息，本题时归纳题，不要在答案中出现题目以外的信息。

bigp

我不太同意arundhati同学的意见。其实excrete按金山词霸的解释：排泄分泌：从血液、组织或器官中分离或消除（废物），这样，就支持了楼主的诠释，但是之所以这一项不对，是因为从文中只能推得Apo-A-IV-2 gene 对胆固醇的升高有抑制作用，但是怎么个抑制方法，确实全然不知。

LuckiPanda

me agree upstairs, not 分泌胆固醇! is 消除胆固醇

excrete cholesterol before it is absorbed into the    bloodstream