Most teens need about 8 to 10 hours of sleep each night. Getting the right amount of sleep is necessary for anyone who wants to do well in tests or sports. Unfortunately, many teens don’t get enough sleep.
Until recently, teens was often blamed for staying up late, oversleeping for school, and falling asleep in class. But recent studies show that their sleep patterns(模式) actually differ from those of adults or kids.
Scientists say that during the teen years, the body’s circadian rhythm, which is controlled by a biological(与生物学有关的) clock in the brain, is temporarily reset, telling a person to fall asleep later and wake up later. This change might arise from the fact that the brain hormone melatonin(褪黑激素) is produced later at night for teens than it is for kids and adults. This can make it harder for teens to fall asleep early.
These changes in the body’s circadian rhythm are in line with a busy time in life. For most teens, the pressure to do well in school is stronger than when they were kids, and it’s harder to get by without studying hard. And teens also have other time demands — everything from sports and other after-school activities to doing a part-time job to save money for college.
Early start times in some schools might also play a role in lost sleep. Teens who fall asleep after midnight may still have to get up early for school, meaning that they might have only 6 or 7 hours of sleep a night. A few hours of missed sleep a night may not seem like a big deal, but it can lead to sleep loss over time.
【小题1】The right amount of sleep is mentioned in Paragraph 1 to ________.| A．show the secret of good sleep |
| B．attract readers’ interest in sleep patterns |
| C．introduce the topic about sleep loss among teens |
| D．discuss the relationship between sleep and performance |
| A．Early start times are the main reason for teens’ sleep loss. |
| B．Teens can get up late to make up for their lost sleep. |
| C．There are biological reasons for teens’ sleeping late. |
| D．A busy schedule has little to do with teens’ sleep patterns. |
| A．The suggestions on how to get enough sleep. |
| B．The reasons why teens don’t get enough sleep. |
| C．The results caused by not getting enough sleep. |
| D．The importance of getting enough sleep for teens. |
