首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Sleep is part of a person’ s daily activity cycle. There are several different stages of sleep, and they too occur in cycles. If
Sleep is part of a person’ s daily activity cycle. There are several different stages of sleep, and they too occur in cycles. If
admin
2012-09-19
68
问题
Sleep is part of a person’ s daily activity cycle. There are several different stages of sleep, and they too occur in cycles. If you are an average sleeper, your sleep cycle is as follows. When you first drift off into slumber (安睡) , your eyes will roll about a bit, your temperature will drop slightly, your muscles will relax, and your breathing were slow and become quite regular. Your brain waves slow down a bit too, with the alpha rhythm of rather fast waves predominating for the first few minutes. This is called stage 1 sleep. For the next half hour or so, as you relax more and more, you will drift down through stage 2 and stage 3 sleep. The lower your stage of sleep, the slower your brain waves will be. Then about 40 to 60 minutes ’after you lose consciousness you will have reached the deepest sleep of all. Your brain waves will show the large slow waves that are known as the delta rhythm. This is stage 4 sleep.
You do not remain at this deep fourth stage all night long, hut instead about 80 minutes after you fall into slumber, your brain activity level will increase again slightly. The delta rhythm will disappear, to be replaced by the activity pattern of brain waves. Your eyes will begin to dart around under your closed eyelids (眼皮) as if you were looking at something occurring in front of you. This period of rapid eye movement lasts for some 8 to 15 minutes and is called REM sleep. It is during REM sleep period, your body will soon relax again, your breathing will grow slow and regular once more, and you will slip gently back from stage 1 to stage 4 sleep -- only to rise once again to the surface of near consciousness some 80 minutes later.
Stage 4 sleep lasts______.
选项
A、about 80 minutes
B、about 40-60 minutes
C、about 30 minutes
D、about 2040 minutes
答案
D
解析
根据文章可知一个睡眠周期大约是80分钟,而stage 4 sleep是睡眠的最后阶段,它发生在入睡后大约40至60分钟时,据此可推出stage 4 sleep持续20至40分钟。
转载请注明原文地址:https://kaotiyun.com/show/BS57777K
0
大学英语四级
相关试题推荐
Haveyoueverwonderedwhatourfutureislike?Practicallyallpeople【C1】______adesiretopredicttheirfuture【C2】______People
Haveyoueverwonderedwhatourfutureislike?Practicallyallpeople【C1】______adesiretopredicttheirfuture【C2】______People
Yogaiscloselyrelatedtothebodyandmindwithallthebreathing,stretching,andmeditating.Inrecentyearsscientificr
A、May29th.B、June29th.C、July29th.D、April29th.B数字推理题。四个选项都是表示日期的名词,因此提问点必定是日期。此题是一道简单的计算题,做题的关键在于听清楚问题中给出的前提条件是学期从8月29日开始,
Intheolddays,childrenwerefamiliarwithbirthanddeathaspartoflife.ThisisperhapsthefirstgenerationofAmericany
A、Bycrushinglargeamountsofstone.B、Bycausingmudorsandtomixwithoceanwater.C、BycreatinglargewavesontheSurface
A、ComparisonB、ContrastC、CausalityD、BiasB归纳题。关于跨文化、跨国籍的婚姻话题,男女交谈一开始就有不同意见。男的认为是个好主意,女的则认为不合适,所以答案选B。此题的关键要理解sound(合理的、好的)的意思
Theviewoveravalleyofatinyvillagewiththatched(草盖的)roofcottagesaroundachurch;adrivethroughanarrowvillagestree
A、Villagelifeinthesouth.B、Customsofthesouth.C、VillagelifeintheNewEnglandstates.D、TheCivilWar.C文中提到Stowe大多数最好的
A、Pauliskeenonsweetfood.B、Paul’steetharenothealthy.C、Pauleatstoomuchsweetfood.D、Pauliscrazyaboutsweets.Asw
随机试题
中国已成为美国第______大进口市场。()
Pelger-Hufit畸型的特点是
麻疹疹前期见麻毒闭肺时可见
女,34岁。2年来月经量多,乏力、心悸。检查面色较苍白。血红蛋白70g/L,白细胞8×109/L,血小板110×109/L,血清铁311g/L。治疗首选
患者男,68岁。睡时汗出,醒时汗止,心悸少寐,神疲气短,面色无华,舌淡脉虚,宜选用
安装平网三要是素负载高度、网的宽度和缓冲的距离,使用3m宽的安全平网时,网底距下方物体表面不得小于()。
学习是在()作用下驱使的。
某日甲乙两代工厂同时向河道内排放未经处理的污水,下列说法正确的是()。
Howmanyaretherequalitycontrolinspectionpoints?
Anothercharacteristicofourlandscapeisitsexquisitemoderation.Itlooksliketheresultofoneofthosehappycompromises
最新回复
(
0
)