课时作业20
Ⅰ.阅读理解(2016·四川高考)
A warm drink of milk before bed has long been the best choice for those wanting a good night's sleep. But now a study has found it really does help people nod off—if it is milked from a cow at night.
Researchers have discovered that “night milk” contains more melatonin (褪黑激素), which has been proven to help people feel sleepy and reduce anxiety.
The study, by researchers from Seoul, South Korea, involved mice being fed with dried milk powder made from cows milked both during the day and at night.
Those given night milk, which contained 10 times the amount of melatonin, were less active and less anxious than those fed with the milk collected during daytime, according to the study published in The Journal of Medicinal Food.
Night milk quickened the start of sleep and caused the mice to sleep longer.
While the effect of cows milk harvested at different time has not been tested on humans up to now, taking melatonin drugs has been suggested to those who are struggling to fall asleep at night.
Previous studies have also indicated that milk can be excellent for helping sleep because of the calcium content, which helps people to relax.
Milk is also sugarfree and additivefree with nutritionists recommending skimmed milk as the best choice before bed as it is the least fattening. The more fat you take in before bedtime, the greater burden you will put on your body at night.
1．According to the text, the mice fed with daytime milk ________.
A．started sleep more easily
B．were more anxious
C．were less active
D．woke up later
2．Which of the following is true of melatonin according to the text?
A．It's been tested on mice for ten times.
B．It can make people more energetic.
C．It exists in milk in great amount.
D．It's used in sleeping drugs.
3．What can be a suitable title for the text?
A．Night Milk and Sleep
B．Fat, Sugar and Health
C．An Experiment on Mice
D．Milk Drinking and Health
4．How does the author support the theme of the text?
A．By giving examples.
B．By stating arguments.
C．By explaining statistical data.
D．By providing research results.
答案与解析
本文是一篇科普说明文。晚上睡前喝一杯热牛奶有助于睡眠是一个常识，那么睡前喝在夜间收集的牛奶对睡眠有哪些影响呢？让我们一起来看看研究者的新发现吧。
1．B 推理判断题。根据第四段可推知，喝了白天挤出来的牛奶的老鼠更活跃、更焦虑。故选B。
2．D 推理判断题。根据关键句“taking melatonin...at night.”可推知，安眠类药品里含有褪黑激素。故选D。
3．A 标题概括题。本文主要介绍了喝晚上挤出来的牛奶对睡眠的好处，因为晚上挤出来的牛奶中含有更多的褪黑激素，所以喝晚上挤出来的牛奶有助于睡眠，还能减轻身体负担。故A项“晚上挤出来的牛奶和睡眠”最能概括文章主旨，适合做标题。故选A。
4．D 写作手法题。本文先用睡前喝牛奶有助睡眠这一传统观点引出主题，即睡前喝晚上挤出来的牛奶不仅有助睡眠，还能减轻身体负担，然后引用了具体的研究结果来进一步论证主题，阐释观点。故选D。
