必修四unit 4课时作业 带答案

必修四Unit4课时作业Ⅰ

Ⅰ.单词拼写

1．The dog ___ communicates _____(传递) its fear to the other animals.

2．Can you g__ guess ______ what he will buy for you on your birthday?

3．Deaf people often use sign language as a means of c__ communication ______.

4．The Prime Minister is to make a_ statement _______(声明) tomorrow.

5．He __ represented ______(代表) our class making a speech at the meeting.

6．When the fierce dog _ approached _______(靠近) her，she hid herself behind the door.

7．I don’t think that we should be seen traveling t ogether—people might m__ misunderstand 8．There was an e__ expression ______ of danger on her face.

9．The boy is very __ curious ______(好奇的) and he is always asking questions.

Ⅱ.翻译句子

1．Tian’anmen Square looks even more beautiful __ with all lights on ____(所有的灯都亮着)．

2．Do you know the man __ wearing a white shirt __ (穿白衬衣的人)?

3．He has experience ____ as well as knowledge _____(也有知识)．

4．They stood there for an hour，__ watching the match ____(观看比赛)．

5．The famous professor came in，__ followed by a group of students _ (后面跟着一群学生)．

6．外国朋友对中国商业的发展很好奇。

The foreign friends are very ___ curious about __ the __ development of business __in China.

7．他不喜欢晚上外出，我也不喜欢。

He doesn’t like to go out in the evening, __ neither do __I.

8．我不喜欢他和他父母说话的方式。

I don’t like the way _ that/in which __ he speaks to his parents.

9．你所说的不太可能与你所做的一样。

What you say is not _ likely to __be the ___ same as _ what you do.

Ⅲ.单项填空

1．Children are always curious ________ the unknown world.

A．forB．toC．of D．about

[解析]be curious about为固定搭配，意为“对……感到好奇”。[答案] D

2．He avoided ________ his opinion on the subject.

A．to give B．givingC．give D．gave

[解析]avoid后接名词或动名词，不能接不定式。[答案] B

3．The ________ manager of our company told us to read the article and get a ________ idea.

A．general; general B．general; opinionC．chief; whole D．/；/

[解析]general manager意为“总经理”；general idea意为“大意”。[答案] A

4．The teacher said that we could ________ ourselves at the class meeting.

A．express B．thinkC．offer D．suggest

[解析]只有express可以放在句中与ourselves搭配，表示“畅所欲言”。[答案] A

5．Shakespeare was ________ a musician ________ a writer.

A．not; but B．both; andC．neither; nor D．either; or

[解析]莎士比亚是世界名人，人们都知道他不是音乐家而是剧作家。[答案] A

6．Your story ________ his in everything ________ small details.

A．agrees with; except B．agrees to; besidesC．agrees; except D．agrees on; besides

[解析]此处agree with意为“与……一致”。全句意为“你的故事和他的一样，只是有些小细节不同”。[答案] A 7．She sat in a chair，________ the letter and ________ herself.

A．to read; smile B．read; smilingC．reading; smiling D．to read; to smile

[解析]句中两个空格内的动词均为现在分词作伴随状语。[答案] C

8．After graduation they still ________ touch with each other ________ sending e-mails.

A．stay in; with B．keep in; byC．get in; by D．close; by

[解析]表示“与……保持联系”用stay/keep in touch with；后一个空用by表方式。B

9．I think he is ________ to win，but I’m not sure.

A．possible B．likelyC．impossible D．certain

[解析]从语义上看，D项肯定不能选；从英语习惯上看，A项和C项也不能选；此题最佳答案为B项。注意：虽然possible和likely均可表示“可能”，但是两者的搭配是不同的，即可以说sb.is likely to do sth.，但不能说sb. is possible to do sth.。[答案] B

10．—Where is the new dictionary?

—It is on the top shelf，out of ________.

A．reach B．sightC．touch D．order

[解析]out of reach意为“够不着”。其他选项构成的含义与句意不符。[答案] A

11．John, I want to apologize ________ you ________ us all.

A．to; to B．to; forC．for; for D．for; to

[解析]前一空to表示“道歉的对象”；后一空for us all表示“代表我们大家”。[答案] B

12．The new comers are curious ________ the things in the room, so no one would like to leave.

A．in B．aboutC．of D．for

[解析]be curious about sth.对(某事物)感到好奇。[答案] B

13．“l can’t do anything with it，”said Bob disappointedly, ________ at the colour TV set.

A．looking B．to lookC．looked D．having looked

[解析]现在分词looking作伴随状语，伴随said这一动作发生。[答案] A

14．The funeral was not for the ________ of the dead，but for the comfort of the living.

A．purpose B．respectC．envy D．impression

[解析]句意为“葬礼不是对死者的尊敬，而是对生者的慰藉”。[答案] B

15．Please come ________ so that I can see you.

A．closely B．closedC．closing D．close

[解析]句意：请走近些，以便我能看见你。close是副词，修饰动词come。[答案] D

Ⅳ.阅读理解

If you can speak English, you know a lot of English words. You can read, speak and understand. But there is another kind of language you need to know—the language of the body, a part of what is called non-verbal communication. All over the world, people “talk” with their eyes. When Japanese people meet, they put their hands together. What do American and British people do?

Americans are more informal than the British. They like to be friendly. They use first name；they ask questions and they talk easily about themselves. When they sit down，they like to relax in their chairs and make themselves comfortable. British people are more quiet. They take more time to make friends. They like to know you before they ask you home. When British and American people meet someone for the first time, they shake hands. They do not usually shake hands with people they know well. Women sometimes kiss their women friends, and men kiss women friends (on one cheek only). When a man meets a man friend，he just smiles，and says “Hello”. Men do not kiss each other. Even fathers and sons do not often kiss each other.

1．When an American man meets a woman friend, he ________.

A．kisses her B．just smilesC．says “Hello” D．shakes hands

[解析]第四段第三句中说到男子亲吻他的女性朋友。[答案] A

2．British people are ________.

A．as quiet as AmericansB．more formal than Americans

C．less friendly than AmericansD．more informal than Americans

[解析]第二段第一句说：美国人比英国人较为不拘礼节(informal)。反之便是：英国人比美国人讲究礼节。[答案] B

3．From the passage we can come to the idea that ________.

A．most of the body language in different countries may be different

B．most of the body language in different countries is the same

C．all the body language in different countries is different

D．none of the body language in different countries is the same

[解析]本文讲了日本人、英国人和美国人的礼仪方面的异同，以不同为主。由此可以推测：不同国家的大多数肢体语言可能是不同的。注意may一词，表可能，因而这一结论是正确的。B项内容在文中找不到支撑句。C项说不同国家里所有的身势语都不相同，这与第四段第一句相冲突。D项的意思同C项，因而也不对。[答案] A 4．Body language is ________.

A．the system of human expression newly invented recently

B．the system of human expression by means of words

C．the system of human expression by sign, movements，etc.

D．a common system of human expression with words and signs

[解析]从第一段可知答案。[答案] C

5．People use body language ________.

A．in Asia B．in AmericaC．in Britain D．all over the world

[解析]从第一段All over the world，people “talk” with their eyes.可知答案。[答案] D

课时作业Ⅱ

Ⅰ.介副词填空

1．He majored ___ in _____ English in Beijing University at that time.

2．He impressed her _ with _______ his honesty.

3．The bus picks ___ up _____ passengers outside the airport.

4．They provide food and clothing ___ for _____ the poor.

5．They were very curious _ about _______ the people who lived upstairs.

6．—It must have been terrible.

—__ On ______ the contrary，I enjoyed every minute.

7．He is crazy _ about _______ basketball and he’s a big fan of Yao Ming.

8．She climbed __ up ______ the stairs to see what was happening.

9．The island was originally circular ____ in ____ shape.

Ⅱ.合并句子

1．The man is my English teacher. He is standing at the gate.

____ The man standing at the gate is my English teacher.__

2．When he was crossing the street, he was knocked down by a car which was rushing.

_____ When crossing the street，he was knocked down by a rushing car

3．A group of students came in and followed the professor.

[答案] A group of students came in，following the professor.

4．Because he was ill, he did not take part in the sports meeting.

[答案]Being ill，he didn’t take part in the sports meeting.

5．I almost fell asleep when I was watching the film which was boring.

[答案]When watching the boring film，I almost fell asleep.

6．There is an old lady. She is sitting under the tree. She is reading a novel.

[答案]There is an old lady sitting under the tree，reading a novel.

7．There were many people in the street. They were watching the fire.

[答案]There were many people watching the fire in the street.

8．He donated some money to the earthquake-hit area. He saw the terrible scenes on TV.

[答案]Having seen the terrible scenes on TV，he donated some money to the earthquake-hit area.

Ⅲ.单项填空

1．—Why did she spend so much time searching shop after shop only for a blouse?

—Oh, she was very ________ about her clothes.

A．specialB．particularC．especial D．unusual

[解析]be particular about意为“对……挑剔”。[答案] B

2．Language was, is and will ________ the chief mean of exchange of ideas.

A．stay B．becomeC．seem D．look

[解析]四个选项都是连系动词，但根据题意应选stay，表示“仍然是”的意思，其他选项均不符合题意。[答案] A

3．European football is played in 80 countries，________ it the most popular sport in the world.

A．making B．makesC．made D．to make

[解析]v．-ing短语作结果状语。[答案] A

4．“We can’t go for an outing in this weather, ”said our teacher，________ out of the window of our classroom. A．looking B．to lookC．looked D．having looked

[解析]动词look与逻辑主语our teacher构成主谓关系。[答案] A

5．A beautiful woman came ________ to the bus stop only ________ the bus had gone.

A．to run; finding B．running; to findC．and ran; found D．running; finding

[解析]running在这里作伴随状语；虽然only to do sth.也作伴随状语，但是表示意想不到的结果。[答案] B 6．________ Monday，rather than ________ at home, I preferred ________.

A．It being; stay; to travelB．Being; to stay; to travel

C．Having been; stay; travelD．It was; to stay; travel

[解析]当分词部分的主语不同于句子的主语时，要用独立主格结构；prefer后面接不定式表示具体要做的事情，prefer to do sth.rather than do sth.，为固定搭配。[答案] A

7．Before ________ yellow, the house should be cleaned thoroughly.

A．painting B．having been paintedC．being painted D．have been painted

[解析]house与paint之间是被动关系，所以用过去分词形式。[答案] C

8．The key ________，I couldn’t enter the office.

A．was lost B．having been lostC．be lost D．being lost

[解析]这里用独立主格结构表示原因。[答案] B

9．________ in the queue for half an hour，Tom suddenly realized that he had left his wallet at home.

A．To wait B．Have waitedC．Having waited D．To have waited

[解析]Tom与wait构成主谓关系且有明显的时间先后顺序，故用having done。[答案] C

10．________ his exercise book, he was scolded by the teacher.

A．Not having handed in B．Having not handed in

C．Not handing in D．Handing not in

[解析]不定式、动名词、分词的否定式都在前面加not。[答案] A

11．________ in such a hurry，his composition has many mistakes.

A．Having written B．WritingC．As writing D．Having been written

composition与write是动宾关系，应该用被动语态，所以A、B、C都不正确。[答案] D

12．________ that some guests were coming, they got the room ready.

A．Having told B．TellingC．Having been told D．To tell

[解析]主语they与tell的关系是动宾关系，要用被动语态。[答案] C

13．________ many times，none of the boys dared swim in that river.

A．Having warned B．Been warnedC．Having warning D．Having been warned

[解析]句子的主语none of the boys与动词warn是动宾关系(表示被动)，因此A、C不选。B项语法错误。分词短语的意思是“被警告过多次”。[答案] D

14．We are doing our best with the ________ resources available.

A．limiting B．limitedC．having limited D．to have limited

[解析]limited为形容词，意思是“有限的”。[答案] B

15．________ the programme, they have to stay there for another two weeks.

A．Not completing B．Not completedC．Not having completed D．Having not completed

[解析]本题考查非谓语动词作状语的用法。根据题意，非谓语动词表示的动作发生在主句动作之前，故应使用

分词的完成式。非谓语动词的否定形式应将not置于非谓语动词之前。

[答案] C

Ⅳ.完形填空

From the time each of my children started school, I packed their lunches. And in each lunch, I __1__ a note. Often written on a napkin(餐巾)，it might be a thank-you for a __2__ moment, a reminder of something we were happily expecting，or a bit of __3__ for the coming test or sporting event.

In early grade school they __4__ their notes. But as children grow older they become self-conscious(有自我意识的)，and __5__ he reached high school, my older son, Marc，informed me he no longer __6__ my daily notes. Telling him that he no longer needed to __7__ them but I still needed to write them，I __8__ until the day he graduated.

Six years after high school graduation, Marc called and asked if he could move __9__ for a couple of months. He had spent those years well，graduating from college, __10__ two internships(实习) in Washington, D. C. , and __11__，becoming a technical assistant in Sacramento. __12__ short vacation visits, however, he had lived away from home. With his younger sister leaving for college, I was __13__ happy to have Marc back. Since I was __14__ making lunch for his younger brother, I __15__ one for Marc，too. Imagine my __16__ when I got a call from my 24-year-old son, __17__ his lunch.

“Did I do something __18__？Don’t you love me __19__，Mom？”were just a few of the questions he threw at me as I __20__ asked him what was wrong.

“My note, Mom, ”he answered. “Where’s my note？”

1．A.carried B．foundC．included D．held

[解析]本句意为：我在每顿午饭中都包括了一张便条。

[答案] C

2．A.difficult B．specialC．comfortable D．separate

[解析] a special moment某一特殊时刻。[答案] B

3．A.congratulation B．improvementC．explanation D．encouragement

[解析]encouragement鼓励，鼓舞。[答案] D

4．A.loved B．answeredC．wrote D．examined

[解析]开始上学的前几年孩子们喜欢便条，所以这里应用loved“喜欢，喜爱”。

[答案] A

5．https://www.sodocs.net/doc/0212913621.html,tely B．by the wayC．by the time D．gradually

[解析]by the time相当于when，引导一个时间状语从句。[答案] C

6．A.received B．understoodC．enjoyed D．collected

[解析]麦迪上高年级，有了自我意识，不再喜欢或欣赏我每天给他写的便条了。所以此处应用enjoyed。[答案] C

7．A.copy B．readC．take D．send

[解析](我)告诉麦迪尽管他不再看那些便条，但我仍然要写。“看便条”应用read。

[答案] B

8．A.held up B．gave upC．followed D．continued

[解析]……于是我就继续(写便条)直到他(麦迪)毕业。“继续”continue。

[答案] D

9．A.out B．homeC．to college D．to Sacramento

[解析]由下文．..，he had lived away from home.可知，麦迪中学毕业后六年没在家里住。所以他打电话问能否回家住两个月，故用move home。[答案] B

10．https://www.sodocs.net/doc/0212913621.html,anizing B．planningC．comparing D．completing

[解析]完成实习(实习结束)应用complete。[答案] D

11．A.hopefully B．finallyC．particularly D．certainly

[解析]“最后，终于”应用finally。[答案] B

12．A.Because of B．Instead ofC．Except for D．As for

[解析]根据上下文可知，麦迪除了简短的假期回家外，其余时间不在家中。“除了”应用except for。[答案] C

13．A.especially B．immediatelyC．equally D．generally

[解析]由于(麦迪的)小妹妹要离开家去上大学，所以“我”特别高兴让麦迪回来住。especially“特别，尤其”，符合题意。[答案] A

14．A.once B．againC．still D．even

[解析]因为我仍然要为麦迪的小弟弟做午饭，所以我也给麦迪准备了一份。still“仍然，依然”。[答案] C 15．A.packed B．fetchedC．bought D．filled

[解析]根据第一自然段的第一句可知，此处应用packed。[答案] A

16．A.fear B．surpriseC．anger D．disappointment

[解析]根据下文“24岁的儿子曾经不想看但现在还想看母亲在午饭中包括的便条，母亲很惊奇”可知，此处应用surprise。[答案] B

17．A.waiting for B．worrying aboutC．caring for D．asking about

[解析]儿子打电话问有关午饭中便条的事，根据下文可知应用asking about。

[答案] D

18．A.wrong B．funnyC．strange D．smart

[解析]据下文Where’s my note？可知，因为母亲在午饭中没有包括便条，所以麦迪问“是我做错什么事了吗？”something wrong错事。

[答案] A

19．A.any more B．enoughC．once more D．better

[解析]因为母亲在午饭中没有包括便条，所以麦迪问“妈妈，难道你不再爱我了吗？”not...any more“不再”。[答案] A

20．A.interestingly B．bitterlyC．politely D．laughingly

[解析]二十多岁的儿子在电话中问的问题让母亲感到好笑，所以笑着问what was wrong，应用laughingly。[答案] D

课时作业Ⅲ

Ⅰ.单词拼写

1．While riding on my way home, I just _ avoided __ (避免) running over a cat.

2．As you _ approach _______(接近) the town, the first building you see is the church.

3．Anyone who breaks the law will be p___ punished _____.

4．In our country，n_ nodding _______ your head i s usually to say “Yes”．

5．Sometimes we can make ourselves understood using g_ gestures _______.

6．I i__ intended ______ to come to your house last night, but it rained.

7．What’s his r_ rank _______ in the army?

8．I’m quite a_ angry _______ with you for your mistake.

9．Are you w_ willing _________ to do public service work without pay?

Ⅱ.翻译句子

1．当有人走近要和你握手时，你最好面带微笑，并友好地伸出手。(approach)

[答案]When someone is approaching you to shake hands with you，you’d better reach out your hand，smiling and friendly.

2．这两个相似的手势竟然表达了如此不同的含义，让我感到很惊讶。(similar)

[答案]It astonished me that the two similar gestures should express such different meanings.

3．打个电话向邀请你吃饭的朋友表示感谢，是有礼貌的。(It’s good manners to...)

It’s good manners to make a telephone to show thanks to your friends who invited you to dinner.

4．政府未来一年的一个主要任务是改善农民的生活条件。(major)

One of the major tasks in the coming year for the government is to improve farmers’ living conditions.

5．对你不应该知道的事情，不要感到好奇。(be curious about)

[答案]Don’t be too curious about the things that you’re not supp osed to know.

6．从他的面部表情上判断，他好像已经知道了事情的真相。(facial expression)

[答案]Judging from his facial expression，he seems to have been told the truth.

7．有一句谚语说的是“入乡随俗”。(There is a saying that...)

[答案]There is a saying that “When in Rome，do as Romans do”．

8．多知道一些身体语言，能够帮助你避免交际中的困难，尤其当你的英语说得不好时。(avoid)

[答案]Learning more about body language can help you avoid some trouble in communication，especially if you can not speak English very well.

9．有些国家的老师会惩罚那些在课堂上没有看他们的学生，对此，肯定有很多人感到奇怪。

(look sb. in the eye)

[答案]Many people must feel it strange that teachers in some countries punish students for their not looking them in the eye.

10．中国是一个属于第三世界的发展中国家。(v.-ing form)

[答案]China is a developing country belonging to the third world.

Ⅲ.单项填空

1．“Respect” and “inspect” are differe nt ________ meaning but similar ________ each other in spelling.

A．in; inB．to; toC．to; in D．in; to

前一空in表示“在……方面”；后一空to与similar搭配表示“与……相似”。[答案] D

2．You can get his help as he is a person who is willing ________ others.

A．helps B．helpingC．to help D．help

[解析]be willing to do为固定搭配，即be willing后只能用不定式。

[答案] C

3．As it was getting late, she ________ the children to hurry up.

A．said B．talkedC．spoke D．told

[解析]在所给选项中，只有D项可以构成tell sb. to do sth.结构，即其后接宾语和宾语补足语结构。[答案] D 4．I don’t really work here; I ________ until the new secretary arrives.

A．just help out B．have just helped outC．am just helping out D．will just help out

题意可理解为说话时的一段时间内所发生的动作，也指临时性的行为，故用现在进行时。C

5．The brothers look very ________. It’s hard to tell them apart.

A．the same B．familiarC．similar D．general

[解析]句意为“兄弟俩看上去很相似，很难把他们区分开”。[答案] C

6．In fact ________ is a hard job for the police to keep order in an important football match.

A．this B．thatC．there D．it

[解析]it在句中作形式主语，其他选项均不能充当形式主语。[答案] D

7．There aren’t many seats left for this concert; you’d better come ________ to ________ that you have one today. A．enough early; make sureB．enough early; be sure of

C．early enough; be sure ofD．early enough; make sure

enough用作副词修饰形容词或副词需后置；be sure of不能接从句，而make sure可以。D

8．We need to develop our imagination and ________ art ________ our teaching.

A．add；up B．add up；toC．add；to D．add；in

[解析]add sth. to sth.意为“把某东西加到某东西上”。[答案] C

9．The Foreign Minister said ，“________ our hope that the two sides will work towards peace.”

A．This is B．There isC．That is D．It is

[解析]分析题干结构可知，that引导主语从句，因此需用it is，it作形式主语；而this，that无此用法；B项意义不当。[答案] D

10．Some students staying up late into the night, ________ their lessons for the coming examination.

A．to prepare B．preparingC．prepare D．was preparing

[解析]从句意上分析，空格处充当伴随状语。不定式不能充当伴随状语，C、D两项是谓语，不符合语法规则。[答案] B

11．All the information we have collected in relation to that case ________ very little.

A．makes up for B．adds up toC．comes up with D．puts up with

[解析]add up to总计为，加起来；make up for弥补(时间)；come up with提出，想出；put up with忍受。[答案] B

12．Jack speaks Chinese ________ he were a Chinese.

A．as if B．even ifC．even though D．although

as if意为“仿佛，好像”，后面引导的从句可用虚拟语气，若是be动词要用were。[答案] A

13．—________ for the glass!

—It’s OK. I’m wearing shoes.

A．Look out B．Walk outC．Go out D．Set out

[解析]本题考查动词短语的意义。由语境可知，此处需表示“当心”之意，只有A项合适。B项意为“走出去”；C 项意为“出去，熄灭”；D项意为“出发，着手做”。[答案] A

14．I’m looking forward with keen anticipation ________ with you and your colleagues.

A．on work B．to workC．on working D．to working

[解析]with keen anticipation表示“带有极大的热情”，作状语用，可以从句中删除，从而可知句中隐含的词组是look forward to，其中to为介词，不可用其他词替代，后面要跟动词-ing形式，所以A、B、C三项排除。[答案] D

15．________ to the right, you will find the house you are looking for. You can’t miss it.

A．You turn B．TurnC．To be turning D．Turning

[解析]此处为现在分词作状语，表示条件。[答案] D

Ⅳ.书面表达

目前，食品安全问题引起了人们的广泛关注。一些生产商为了降低成本、追求利润，不严把质量关，安全措施不到位，致使一些劣质或有害的食品流入市场，这些产品对人们的健康产生了极大的危害。请你就此事给一家英文报刊写封信，谈谈个人看法并呼吁整个社会关注此事。

要求：1.词数在100左右；

2.开头和结尾已给出，不计入总词数。

参考词汇：利润profit安全措施safety measures

[答案]Dear Sir，

I’ m writing to talk about the problems of food safety nowadays. In order to reduce the cost and make more profits, some food companies don’ t take necessary safety measures to guarantee the food quality. As a result, more and more low-quality food flows into the market, which does a lot of harm to consumers’ health.

In my opinion, food is essential to human beings. We can not live without proper food. If no notice were taken of food safety, the health of the whole nation would be in danger. So I call on the whole society to pay attention to the problems and take action to get rid of low-quality food. Only in this way can we live a healthier life.

Yours truly，

Li Hua

[名师点评]

1．文章符合书信的格式要求，要点齐全，条理清晰，结构完整。

2．in order to，as a result，call on，get rid of等高级词汇，虚拟语气，倒装结构的应用显示了作者较强的语言驾驭能力。

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4．下列有关细胞间信息交流的叙述中，正确的是() A．细胞间信息交流是细胞膜的功能之一，体现了细胞膜的选择透过性 B．神经递质与突触后膜上的受体结合后，即被受体转运到突触后膜上，使后膜兴奋或抑制 C．与胰岛素和甲状腺激素结合的受体可能相同，也可能不同D．细胞间信息交流的方式多种多样，可以是细胞接触传递信息，也可以通过介质传递 5．(2019·衡阳八中质检)如图表示细胞膜的亚显微结构，其中a和b 为物质的两种运输方式，下列对细胞膜结构和功能的叙述错误的是() A．若图示为肝细胞膜，则尿素的运输方向是Ⅱ→Ⅱ B．细胞间的识别、免疫、细胞的癌变与Ⅱ有密切的关系 C．适当提高温度将加快Ⅱ和Ⅱ的流动速度 D．b过程不需要A TP，a过程未体现膜的选择透过性这一生理特性6．(2019·长沙月考)下列关于细胞膜的流动镶嵌模型说法正确的是() A．罗伯特森利用光学显微镜提出了“亮—暗—亮”的三明治结构是一

种静态模型 B．利用放射性同位素标记法将小鼠和人细胞膜上的蛋白质做标记的实验，证明了细胞膜具有一定的流动性 C．细胞膜上绝大多数的蛋白质和磷脂双分子层都具有一定的流动性D．欧文顿利用了化学上的“相似相容原理”解决了脂溶性物质为什么更容易进入细胞，是因为细胞膜上具有大量的磷脂和少量的固醇7．(2019·枣庄学情调查)关于细胞核的叙述，正确的是() A．细胞核行使遗传功能的结构是核孔 B．核糖核苷酸只能通过核孔进入细胞核 C．细胞核控制细胞所有的遗传特性 D．没有细胞核也能合成蛋白质 8．心房颤动(房颤)是临床上最常见并且危害严重的心律失常疾病，最新研究表明，其致病机制是核孔复合物的运输障碍(核孔复合物是位于核孔上与核孔的结构和功能密切相关的物质)，据此分析正确的是() A．核膜由两层磷脂分子组成，房颤的成因与核膜内外的信息交流异常有关 B．核孔运输障碍发生的根本原因可能是编码核孔复合物的基因发生

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人教版必修一unit4语法:定语从句强化训练题一.课文原句感知 1．But the one million people of the city，______thought little of these events，were asleep as usual thatnight. 2．It was felt in Beijing，______is more than two hundred kilometers away. 3．The number of people _____were killed or seriously injured reached more than 400,000.4．Then，laterthatafternoon， anotherbigquake______wasalmostasstrongasthefirstoneshookTangshan. 5．The army organized teams to dig out those______were trapped and to bury the dead. 6．Workers built shelters for survivors_________homes had been destroyed. 二．用适当的关系代词填空 （1） 1．The building________wall is white is my uncle's house. 2．I know the boy________you are looking for. 3．Will you please lend me the very book________you bought yesterday? 4．The student________the teacher praised at the class meeting is our monitor. 5．The season________comes after spring is summer. 6．This is the museum________we visited last Saturday. 7．Is this the museum________you visited last Saturday? 8．I found some photos of interesting places________were not far away from our city. 9．The boy with________John spoke is my brother.

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课时作业(十一) 1．在等差数列{a n }中，已知a 1＝2，a 2＋a 3＝13，则a 4＋a 5＋a 6等于( ) A ．40 B ．42 C ．43 D ．45 答案 B 解析 ∵a 2＋a 3＝13，∴2a 1＋3d ＝13.∵a 1＝2，∴d ＝3. 而a 4＋a 5＋a 6＝3a 5＝3(a 1＋4d )＝42. 2．在等差数列－5，－312，－2，－1 2，…中，每相邻两项之间插入一个数， 使之组成一个新的等差数列，则新数列的通项公式为( ) A ．an ＝34n －23 4 B ．an ＝－5－3 2(n －1) C ．an ＝－5－3 4(n －1) D ．an ＝5 4 n 2－3n 答案 A 解析 首项为－5，公差为－312＋52＝3 4， ∴an ＝－5＋(n －1)·34＝34n －23 4 . 3．若a ，b ，c 成等差数列，则二次函数y ＝ax 2＋2bx ＋c 的图像与x 轴交点的个数是( ) A ．0 B ．1 C ．2 D ．1或2 答案 D 解析 ∵a 、b 、c 成等差，∴2b ＝a ＋c . ∴Δ＝(2b )2－4ac ＝(a ＋c )2－4ac ＝(a －c )2≥0.

4．数列{an }中，a 1＝15,3an ＋1＝3an －2，那么该数列中相邻两项的乘积为负数的是( ) A ．a 21和a 22 B ．a 22和a 23 C ．a 23和a 24 D ．a 24和a 25 答案 C 解析 由3an ＋1＝3an －2可知{an }为等差数列，又a 1＝15， ∴an ＝15＋(n －1)·(－23)＝－23n ＋473＝47－2n 3. 令an ·an ＋1<0，即47－2n 3· 47－n ＋ 3<0. 可得4520的等差数列{a n }的四个命题： p 1：数列{a n }是递增数列； p 2：数列{na n }是递增数列； p 3：数列{a n n }是递增数列； p 4：数列{a n ＋3nd }是递增数列． 其中的真命题为( ) A ．p 1，p 2 B ．p 3，p 4 C ．p 2，p 3 D ．p 1，p 4 答案 D 解析 如数列为{－2，－1,0,1，…}，则1×a 1＝2×a 2，故p 2是假命题； 如数列为{1,2,3，…}，则a n n ＝1，故p 3是假命题，故选D 项． 6．(2013·广东)在等差数列{a n }中，已知a 3＋a 8＝10，则3a 5＋a 7＝________.

人教新课标高中生物必修二第1节 孟德尔的豌豆杂交实验(一) 第1课时 提高练习

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C ．Q

b >1，∴lg a ·lg b 1 2(lg a ＋lg b )，故选B. 4．下列不等式一定成立的是( ) A ．x ＋1 x ≥2 B.x 2＋2 x 2＋2≥ 2 C.x 2＋3x 2＋4≥2 D ．2－3x －4 x ≥2 【答案】 B 【解析】 A 项中当x <0时，x ＋1 x <0<2，∴A 错误． B 项中，x 2＋2 x 2＋2＝x 2＋2≥2，∴B 正确． 而对于C ，x 2＋3x 2＋4＝x 2 ＋4－1x 2＋4 ， 当x ＝0时，x 2＋3x 2＋4＝3 2<2，显然选项C 不正确． D 项中取x ＝1,2－3x －4 x <2，∴D 错误． 5．设0

高中生物必修二课时训练第一章第二节孟德尔的豌豆杂交实验二

第二节孟德尔的豌豆杂交实验（二） 一、选择题 1．下列有关孟德尔遗传规律的说法错误的是() A．叶绿体基因控制的性状遗传不遵循孟德尔遗传规律 B．受精时，雌雄配子的结合是随机的，这是得出孟德尔遗传规律的条件之一 C．孟德尔发现分离定律与自由组合定律的过程运用了假说—演绎法 D．基因型为AaBb的个体自交，其后代一定有四种表现型和9种基因型 解读：孟德尔遗传规律适用于真核生物有性生殖过程中核基因的遗传；在受精过程中雌雄配子随机结合且机会均等；孟德尔研究分离定律与自由组合定律时用的方法是假说—演绎法；孟德尔用统计学的方法得出了杂交或自交后代出现一定的分离比，这是对多数个体及后代统计的结果，而一个个体自交具有偶然性，很多情况下不表现相应的表现型、基因型及一定的比例，故D项错误。 答案：D 2．四籽野豌豆的染色体数目为2n＝12，现有—个基因型为Mm的野豌豆植株，所结豆荚中有三个饱满豆粒和一个“空瘪粒”。下列有关分析正确的是() A．该豆荚果皮的基因型是Mm的概率为1/2 B．该豆荚中所结三粒种子种皮中的细胞含有18条染色体 C．所结三粒种子的基因型都是Mm的概率为1/8 D．每个花粉中含有2个精子，因此该豆荚至少需要2粒花粉才能得到4粒种子 解读：豆荚的果皮和种皮与母本植株的基因型、染色体数目相同；被子植物进行双受精，因此该豆荚至少需要4粒花粉才能得到4粒种子；豌豆自花传粉，闭花受粉，所结种子的基因型为Mm 的概率为1/2，三粒种子的基因型都是Mm的概率为1/8。 答案：C 3．某育种专家在农田中发现一株大穗不抗病的小麦，自花授粉后获得160粒种子，这些种子发育成的小麦中有30株大穗抗病和若干株小穗抗病，其余的都不抗病。若将这30株大穗抗病的小麦作为亲本自交，在其F中选择大穗抗病的再进行自交，理论上F中能稳定遗21传的大穗抗病 小麦占F中所有大穗抗病小麦的() 2 A．2/10 B．7/10 C．2/9 D．7/9 解读：本题考查基因分离定律的应用。首先由题意确定大穗不抗病是显性性状。所以作1211为亲本的大穗抗病小麦的基因型为AAbb和Aabb，自交后代F中大穗抗病的为AAbb和 13323- 1 - / 8 327AabB。在大穗抗病中，AAbb和Aabb分别占、。再进行自交，F中大穗抗病的为AAbb 255101771和Aabb，理论上F中能稳定遗传的大穗抗病小麦占F中所有大穗抗病小麦的÷(＋)＝225101057。9答案：D 4．已知位于常染色体上的两对独立遗传的基因控制着鸡羽毛色素的产生和沉积。在一个位点上，显性基因可产生色素，隐性基因则不产生色素；在另一位点上，显性基因阻止色素的沉积，隐性基因则可使色素沉积。小鸡羽毛的着色，必须能产生并沉积色素，否则为白色毛。如果表现型为白色的鸡(两位点均为隐性纯合子)和另一种表现型为白色的鸡(两位点均为显性纯合子)进行杂交，