[单项选择]

Late-Night Drinking

Coffee lovers beware. Having a quick "pick-me-up" cup of coffee late in the day will play havoc with your sleep. As well as being a stimulant, caffeine interrupts the flow of melatonin, the brain hormone that sends people into a sleep.
Melatonin levels normally start to rise about two hours before bedtime. Levels then peak between 2 am and 4 am. before falling again. "It’s 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 caffeinated coffee halves the body’s 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 decaf. On average, subjects slept 336 minutes
A. melatonin levels need to be raised.
B. neurohormone can wake us up.
C. coffee is a stimulant.
D. decaf is a caffeinated coffe

[单项选择]
Coffee lovers beware. Having a quick "pick-me-up" cup of coffeel late in the day will play havoc with your sleep. As well as being a stimulant, caffeine interrupts the flow of melatonin, the brain hormone that sends people into a sleep.
Melatonin levels normally start to rise about two hours before bedtime. Levels then peak between 2 a.m. and 4 a. m. , before falling again. "It’s 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 caffeinated coffee halves the body’s 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
A. melatioin levels need to be raised
B. neurohormone can wake us up
C. coffee is a stimulant
D. decal is a caffeinated coffee

[单项选择]

Late-Night Drinking
Coffee lovers beware. Having a quick "pick-me-up" cup of coffee late in the day will play havoc with your sleep. As well as being a stimulant, caffeine interrupts the flow of melatonin, the brain hormone that sends people into a sleep.
Melatonin levels normally start to rise about two hours before bedtime. Levels then peak between 2 am and 4 am, before falling again. "It’s the neurohormone that controls our sleep, and tells our body when to sleep and when to wake," says Maurice Ohayon of the Stanford Sleep Epiderniology Research Center at Stanford University in California. But researchers in Israel have found that caffeinated coffee halves the body’s 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
A. coffee lovers sleep less than those who do not drink coffee.
B. we should not drink coffee after supper:
C. people sleep more soundly at midnight than at 3 am.
D. if we feel sleepy at night, we should go to bed immediately.

[单项选择]

Coffee lovers beware. Having a quick "pick-me-up" cup of coffee late in the day will play havoc with your sleep. As well as being a stimulant, caffeine interrupts the flow of melatonin, the brain hormone that sends people into a sleep.
Melatonin levels normally start to rise about two hours before bedtime. Levels then peak between 2 am and 4 am, before falling again. "It’s 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 caffeinated coffee halves the body’s 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 amoun
A. Different effects of caffeinated coffee and decal on sleep.
B. Different findings of Lotan Shilo and a team about caffeine.
C. The fact that the subjects slept 415 minutes per night after drinking decaf.
D. The proof that the subjects took half an hour to fall asleep.