以下是引用wujie_ren在2004-1-19 13:16:00的发言:
The key is D, but what’s wrong with B and E? (E) Raising the level of neurotransmitters in the brain effectively relieves depression. The article says that Carbohydrates boost the brain’s levels of serotonin, a neurotransmitter that improve the mood, that means raising the level of N, improve the mood, and act the same way as some antidepressants.
(B) Lack of sunlight lowers the level of serotonin in the brain. The article says that many people suffer from a specific type of seasonal depression caused by lack of sunlight, but carbohydrates boost the brain's levels of serotonin. Can that mean lack of sunlight lowers the level of serotonin.
in e,u considered"neurotransmitter=serotonin".However,there may be several kinds of neurotransmitters,and serotonin is just a kind of it.u don't know whether raising other kinds of neuro- can improve the mood.
in b,carbonhydrates not=sunlight. even though carbonhydyrates=sunlight,we can't infer that lack of carbon- lower the serotonin from its function of boosting it.
the correct answer,D,we can infer from 'Carbohydrates, boost the brain’s levels of serotonin. In this respect, carbohydrates act on the brain in the same way as some antidepressants' here the bridge is"carbo- = some antidepressants"
个人理解=) |