GWD-29-Q40

trackofheart

GWD-29-Q40
Mice that have been given morphine are very likely to develop blood poisoning because bacteria that normally reside in the intestine typically respond to morphine by migrating into the bloodstream.  However, when mice are given both morphine and the new drug naltrexone, blood poisoning is much less frequent, although it does still occur.  These results provide support for researchers’ prediction that naltrexone will turn out to be toxic to certain types of bacteria.
Which of the following, if discovered to be true, would most seriously weaken the support for the researchers’ prediction?

A.    After being administered to mice, naltrexone does not pass from the bloodstream into the intestine.
B.    Naltrexone inhibits morphine from triggering the migration of intestinal bacteria into the bloodstream.
C.    Mice that have been given naltrexone but not morphine have no greater risk of developing blood poisoning than do mice that have not been given either substance.
D.    The increased risk of blood poisoning is not the only harmful effect on mice of being given morphine.
E.    Conditions other than the presence of intestinal bacteria in the bloodstream can cause blood poisoning in mice.
结论是：These results provide support for researchers’ prediction that naltrexone will turn out to be toxic to certain types of bacteria.
重点在于说N对于细菌有毒害作用。潜台词是说，因为有M存在，细菌还是进到老鼠的血液了，只是因为N毒害了细菌，所以老鼠不生病了
而B选项说的是N 阻止M让细菌进入血液。

C 为什么不对呢？
不是用实验组是 : M 和N 一起作用
    而对照组是： 只有N 没有M  
为啥C 不对呢？

flyfairy019

原题结论：N能起到杀死某类细菌的作用。

问削弱
B：N并不能杀菌，只是起到防止细菌进入血管的作用。

hjbb1027

题目说的是N对细菌有毒能杀死细菌，选B就是，实际N只是阻隔了吗啡对细菌起作用，它本身对细菌并没有毒能杀死细菌

C说的是只注射N但不注射吗啡的老鼠没有更高的风险患血液中毒，并没有weaken题目中N能杀死细菌这一点，所以C不对

voleroiseau

老实说，考场上还能考虑的如此清晰的逻辑关系吗？再说一次，C和B的逻辑重心不一样，我只能解释这么多了，其实逻辑关系我都没看懂。

trackofheart

而B选项说的是N 阻止M让细菌进入血液。
N是阻止而不进入 ，不也是 对细菌有作用吗？

voleroiseau

还是看有关无关吧，你要看选项的重心是在说什么事情，C选项明显是在

说老鼠如何，B就是说直接说Naltrexone如何作用了morphine