Late-Night Drinking
Melatonin levels normally start to rise about two hours before bedtime. Levels then peak between 2 am and 4 am, before falling again3. Its the neurohormone that controls our sleep and tells our body when to sleep and when to wake, says Maurice Ohayon of the Stanford Sleep Epidemiology Research Center at Stanford University in California. But researchers in Israel have found that caffcinated coffee halves the bodys levels of this sleep hormone. Lotan Shilo and a team at the Sapir Medical Center in Tel Aviv University found that six volunteers slept less well after a cup of caffeinated coffee than after drinking the same amount of decal. On average, subjects slept 336 minutes per night after drinking caffeinated coffee, compared with 415 minutes after decal. They also took half an hour to drop off4 - twice as long as usual - and jigged around5 in bed twice as much.
Because it can take many hours to eliminate caffeine from the body, Ohayon recommends that coffee lovers switch to decaf after lunch.
A melatonin levels need to be raised.
C coffee is a stimulant.
2. Which of the following tells us how caffeine affects sleep?
B Caffeine interrupts the flow of the hormone that prevents people from sleeping.
D Caffeine stays in the body for many hours.
A Different effects of caffeinated coffee and decaf on sleep.
C The fact that the subjects slept 415 minutes per night after drinking decaf.
4. What does the experiment mentioned in paragraph 4 prove?
B There are more melatonin concentrations in caffeine drinkers urine sample.
D Caffeine drinkers produce less sleep hormone.
A coffee lovers sleep less than those who do not drink coffee.
C people sleep more soundly at midnight than at 3 am.
沪教版小学英语一年级下册教案unit1课时3
沪教版小学英语一年级下册教案unit1课时1
上海版牛津一年级英语教案 Unit 3 My abilities
一年级英语上册Unit1 My classroom第三课时教案
上海牛津版一年级英语下册Unit9 Revision第二课时教案
沪教牛津版小学英语一年级上册 Unit 3 第二课时教案
一年级英语上册教案Unit1 My classroom第一课时教案
上海牛津版一年级英语Unit 9 Revision单元分析教案
上海牛津版一年级英语下册Unit2 Small animals第五课时教案
上海牛津版一年级英语Unit7 My family教案
一年级英语教案Module1 unit6 Mid-Autumn Festival
新课标小学英语第一册期末考试百词范围
上海牛津版一年级英语下册Unit9 Revision第一课时教案
一年级英语下册Unit2 Small animals教案2
上海牛津版一年级英语下册Unit2 Small animals教案
沪教牛津版一年级英语上册教案Unit1 My classroom第二课时
上海牛津版一年级英语Unit2 Small animals第四课时教案
牛津版一年级英语上册教案Unit4 My bag第一课时
牛津版一年级英语上册unit5 Fruit教案(1)
小学一年级英语下册Unit2 Small animals教案1