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
How does food affect mood and mind? The answer may he in the chemistry of the brain and nervous system. Molecules called neurotr
How does food affect mood and mind? The answer may he in the chemistry of the brain and nervous system. Molecules called neurotr
admin
2016-09-21
50
问题
How does food affect mood and mind? The answer may he in the chemistry of the brain and nervous system. Molecules called neurotransmitters(神经传递素)are chemical messengers. They carry a nerve impulse across the gap between nerve cells. The release of neurotransmitter molecules from one neuron and their attachment to receptor sites on another keep a nerve impulse moving.
Nerve impulses carry messages from the environment to the brain, for example, the pain you feel when you stub(踢碰)your toe. They also carry messages in the other direction, from the brain to the muscles. That’s why you back away from the obstacle that initiated the pain signal and exclaim, "Ouch!"
"Many neurotransmitters are built from the foods we eat," says neuroscientist Eric Chudler of the University of Washington. Too little or too much of a particular nutrient in the diet can affect their production, Chudler says. For example, tryptophan from foods such as yogurt, milk, bananas, and eggs is required for the production of the neurotransmitter serotonin. Phenylalanine from beets, almonds, eggs, meat, and grains goes into making the neurotransmitter dopamine.
Dozens of neurotransmitters are known; hundreds may exist. Their effects depend on their amounts and where they work in the brain. The neurotransmitter serotonin, for example, is thought to produce feelings of calmness, relaxation, and contentment. Drugs that prevent it from being taken again(into the neuron that released it)are prescribed to treat depression. In at least some healthy, nondepressed people, carbohydrate foods seem to enhance serotonin production and produce similar effects. "It is the balance between different neurotransmitters that helps regulate mood," Chudler says.
Proper nutrition may also enhance brainpower. Choline is a substance similar to the B vitamins. It’s found in egg yolks, whole wheat, peanuts, milk, green peas, liver, beans, seafood, and soybeans. The brain uses it to make the neurotransmitter acetylcholine. To test the effects of choline on memory and learning, researchers at the Massachusetts Institute of Technology gave memory tests to college students before increasing the amount of choline in their subjects’ diets. Later, they retested. On the average, memories were better, and the students learned a list of unrelated words more easily.
The function of neurotransmitters can be best compared to that of_____.
选项
A、a transport vehicle
B、a protective shield
C、a power plant
D、a food factory
答案
A
解析
从第1段第3句末的messenger和第4句中的carry...across可以知道neurotransmitters就像传递信息的信使,有“运输、输送”信息的功能,因此,本题应选A。
转载请注明原文地址:https://kaotiyun.com/show/zjY7777K
0
大学英语四级
相关试题推荐
Itwasoncethoughtthatairpollutionaffectedonlytheareaimmediatelyaroundlargecitieswithfactoriesandheavyautomobil
CreativeBookReportIdeasA)Areyouatalossforcreativebookreportideasforyourstudents?Ifyes,thenthisarticlewill
CreativeBookReportIdeasA)Areyouatalossforcreativebookreportideasforyourstudents?Ifyes,thenthisarticlewill
Doyoufindgettingupinthemorningsodifficultthatit’spainful?Thismightbecalledlaziness,butDr.Kleitmanhasanew
Psychologiststakeopposingviewsofhowexternalrewards,fromwarmpraisetocoldcash,affectmotivationandcreativity.Beha
WriteacompositionentitledALetterApplyingforaBankLoan.Youshouldwriteatleast120wordsbutnomorethan180wordsa
Inmanycountries,authorityisseldomquestioned,eitherbecauseitishighlyrespected,orbecauseitis【B1】_______.Sometimes
Crimeisincreasingworldwide.Thereiseveryreasontobelievethe【B1】_____willcontinuethroughthenextfewdecades.Crimera
Crimeisincreasingworldwide.Thereiseveryreasontobelievethe【B1】_____willcontinuethroughthenextfewdecades.Crimera
Inrecentyears,moreandmoreforeignersareinvolvedintheteachingprogramsoftheUnitedStates.Boththeadvantagesandth
随机试题
某公安局6月份发生如下经济业务,请编制会计分录。(1)收到财政部门拨来的预算经费300万元。(2)从银行提取现金35万元,准备用于发放工资。(3)购入有价证券12万元,已从银行转账。(4)发放职工工资34万元,职工王某出差未归,尚未领取工资1万元。
A.3/4冠B.金属烤瓷全冠C.铸造开面冠D.塑料全冠E.铸造金属全冠后牙固定桥咬合较紧,第二磨牙固位体可选择
股份公司向外国和我国香港、澳门、台湾地区投资者发行的股票,称为()。
下列关于个人住房贷款利率和还款方式的表述,错误的是()。
根据以下情境材料,回答下列问题。某村的工地由政府承包给其他工程负责人,当地村民不服,把项目经理打成轻微伤,公安民警把打人的村民带回公安局。该村的其他村民不服,跑到工地闹事,阻止施工,并向公安局施压要求放人。当地的村干部也认为工程应由本村承包,也在
A、 B、 C、 D、 C
[*]
int型public成员变量MAX_LENGTH,该值保持为常数200,则定义这个变量的语句是______。
设有表示学生选课的3张表,学生表S(学号,姓名,性别,年龄,身份证号)、课程表C(课号,课名)、选课表SC(学号,课号,成绩),则表SC的关键字(键或码)为()。
下列设备组中,完全属于外部设备的一组是
最新回复
(
0
)