【小题1】D
【小题2】A
【小题3】D
【小题4】B
请选择年级高一高二高三请输入相应的习题集名称(选填)：
科目：高中英语
来源：陕西省宝鸡中学2010届高三适应性训练（英语）
题型：阅读理解
第二部分：阅读理解（共20 小题。第一节共15 小题，每题2分；第二节共5 题，每题2分；共40 分）阅读下列短文，从每题所给的四个选项& A．B．C．D中选出最佳选项。A Unnoticed and unappreciated for five decades，a large female turtle （龟）with a stained（彩色的），leathery（粗而硬的） shell is now a precious commodity（物品）in Changsha’s old zoo．She is fed on a special diet of raw meat．Her small pool has been covered with glass which can defend it from bullets．A special camera monitors her movements．A guard is posted at night． The purpose is simple：the turtle must not die． Earlier this year，scientists concluded that she was the planet’s last known female Yangtze giant soft shell turtle．She is about 80 years old and weighs almost 90 pounds． As it happens，the planet also has only one known male．He lives at a zoo the city of Suzhou．He is 100 years old and weighs about 200 pounds．They are the last hope of saving a species believed to be the largest freshwater turtles in the world． “It’s a very dangerous situation,” said Peter Pritchard, a famous turtle expert in the United States，who has helped try to save the species．、 For many Chinese people，the turtle is the symbol of health and long life，but the last two Yangtze giant soft-shell creatures show the threatened state of wildlife and biodiversity（生物多样性）in China．Pollution, hunting and over development are destroying natural habitats，and also endangering the plant and the animal population． China contains some of the world’s richest treasures of biodiversity, yet the latest major survey of plants and animals shows a discouraging picture．Nearly 40 percent of all mammal species in China are now endangered, Scientists say．For plants，the situation is worse；70 percent of all nonflowering plant species and 86 percent of flowering species are considered threatened．46．Why is the turtle in Changsha specially cared? A．She has been unnoticed and unappreiated five decades． B．She can be sold at a high price． C．She is the planet’s last known female Yangtze giant soft-shell turtle． D．She is old and heavy．47．Which of the following statements is TRUE according to the text? A．The turtle in Changsha is precious because it is the symbol of health and long life． B．Peter Pritchard believes the female turtle is the largest freshwater turtle in the world． C．The female turtle is in a dangerous situation where she may be killed． D．The female turtle in Changsha and the male turtle in Suzhou are the last hope of saving the largest freshwater turtle species in the world．48．According to the text ________in China． A．there are the richest species of living things B．wild plants and animals are becoming fewer C．turtles are specially protected D．the situation of plants is better than that of mammal species49．The last paragraph proves the threatened state of wildlife and biodiversity in China by__________ ． A．facts and numbers&&&&&&&&&&&&&&&&&&&&& B．Peter Pritchard’S words C．teaching theory&&&&&&&&&&&&&&&&&&&&&&& D．telling a story
科目：高中英语
来源：四川省南充高中2010届高三下学期4月月考
题型：阅读理解
第二部分：阅读理解（共两节，满分50分）第一节：阅读下面短文，从短文后各题所给的四个选项（A, B, C, D) 中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。（共20小题，每小题2分，共40分）AA university graduate described as a “respectable and intelligent” woman is seeking professional help after being convicted of shoplifting for the second time in six months.Ana Luz, recently studying for PhD has been told she could end up behind bars unless she can control the desire to steal from shops.Luz, who lives with her partner in Fitzwilliam Road, Cambridge, admitted stealing clothes worth 9.95 pounds from John Lewis in Oxford Street, London, on March 9.Phillip Lomoyne, prosecuting(起诉), said Luz selected some clothes from display and took them to the ladies’ toilet in the store, when she came out again she was wearing one of the skirts she had selected, having taken off the anti-theft security alarm.She was stopped and caught after leaving the store without paying, Mr. Lomoyne said.He added that she was upset on her arrest and apologized for her actions.Luz, 28, was said to have been convicted of shoplifting by Cambridge judges last October, but Morag Duff, defending said she had never been in trouble with the police before this.“She is ashamed and embarrassed but doesn’t really have any explanation why she did this,” Miss Duff said. “She didn’t intend to steal when she went into the store. She is at a loss to explain it. She is otherwise a very respectable and intelligent young lady. She went to her doctor and asked for advice because she wants to know if there is something in particular that caused her to do this.”Judge David Azan fined Luz 50 pounds, and warned: “You have got a criminal record. If you carry on like this, you will end up in prison, which will ruin your bright future you may have.”Luz achieved a degree in design at university in her native Spain, went on to a famous university in Berlin, Germany for her master’s degree and is now studying for a PhD at Cambridge University, UK.41．What is Ana Luz’s nationality? A．American.&&& B．British.&& C．Spanish.&&& D．German.42．What does the underlined sentence “She is at a loss to explain it” mean?A．In her opinion it was a loss to the clothes shops where she stole things.B．She doesn’t have any idea why she has the desire to steal from shops.C．She thinks it is a loss for her to explain why she stole things from shops.D．Personally she feels ashamed and embarrassed for her shoplifting actions.43．Which of the following best explains the meaning of the word “shoplifting” used in the passage?A．Carrying goods in a lift for a shop.&&&& B．Taking goods to the ladies’ toilet.C．Selecting some goods from a display.&& D．Taking goods from a shop without paying.44．From the passage we can learn that________.A．Ana Luz has already got her PhD at Cambridge University, UKB．Ana Luz is ashamed and embarrassed and knows why she often did soC．the university graduate will be put in prison if she steals in shops once moreD．Phillip Lomoyne is the “respectable and intelligent” woman’s defense(辩护) lawyer45．What would be the best title for the passage?A．Shoplifting Shame of a PhD Student.B．Apologizing for the Actions in Shops.C．Seeking Professional Help from Experts.D．Controlling the Desire to Steal from Shops.
科目：高中英语
来源：浙江省镇海市2010届高三模拟考试试题（英语）
题型：阅读理解
第二部分：阅读理解（第一节20小题；第二节共5小题；每小题2分，满分50分）
第一节：阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项。
&&&&&&&& When
I was an education official in Palo Alto, California．Polly Tyner, the president of
our school board, wrote a letter that was printed in the Palo Alto Times．Polly’s son, Jim, had great
difficulty in school．He was classified as educationally disabled and required a great
deal of patience on the part of his parents and teachers．But Jim was a happy kid with a
great smile that lit up the room．His parents acknowledged his academic difficulties, but always tried
to help him see his strengths so that he could walk with pride．Shortly after Jim finished high
school, he was killed in a motorcycle accident．After his death, his mother submitted this letter
to the newspaper．
&&&&&&&& Today
we buried our 20-year-old son．He was killed instantly in a motorcycle accident on Friday night．How I wish I had known when I
talked to him last that it would be the last time．If I had only known I would have said, “Jim, I
love you and I’m very proud of you．”
&&&&&&&& I
would have taken the time to count the many blessings he brought to the lives
of the many who loved him．I would have taken the time to appreciate his beautiful smile, the
sound of his laughter, his genuine love of people．
&&&&&&&& When
you put all the good qualities on the scale and try to balance all the
irritating phenomena such as the radio which was always too loud, the haircut
that wasn’t to our liking, the dirty socks under the bed, etc．, your angry feelings won’t
amount to much．
&&&&&&&& I
won’t get another chance to tell my son all that I would have wanted him to
hear, but, other parents, you do have a chance．Tell your young people what you would want them to
hear if you knew it would be your last conversation．The last time I talked to Jim
was the day he died．He called me to say, “Hi, Mom! I just called to say I love you．Got to go to work．Bye．” He gave me something to
treasure forever．
&&&&&&&& If
there is any purpose at all for Jim’s death, maybe it is to make others
appreciate more of life and to have people, especially family members, take the
time to let each other know just how much we care．
1．According to the passage, we know that ____．
&&&&&&&& A．Jim kept to himself&&& B．Jim did very well in his
studies
&&&&&&&& C．Jim’s parents were patient with
him&&&&&&&& D．Jim failed to finish his high
school
2．The underlined word “irritating” in Paragraph 4 means ____．
&&&&&&&& A．annoying&&&&&&&&&&&& B．aggressive& &&&& C．impatient&&&&&&&&&&& D．thrilling
3．By writing the letter printed in the Palo Alto Times, the author
intends to ____．
&&&&&&&& A．mourn her son’s sudden death in
a traffic accident
&&&&&&&& B．remind people to be cautious of
motorcycles
&&&&&&&& C．advise people to take the
chance to express their love in time
&&&&&&&& D．appreciate more of life than
ever before
4．What can be the best title of the passage?
&&&&&&&& A．Love Your Family．&&& B．Do It Today．
&&&&&&&& C．Walk with Pride．&&&& &&&
D．Appreciate Smiles．
科目：高中英语
来源：江苏省学年度高一下学期期中考试英语试卷
题型：阅读理解
第二部分：阅读理解：（共15小题，每小题2分，满分30分）
阅读下面的短文，然后从A、B、C、D四个选项中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。
My father came to the United States as a
Ukrainian immigrant （移民）when he was 14 years old. Unable to speak English but willing to do
anything to succeed, he learned the language, and became a barber. He put his
two daughters, my sister and me, through college during a time when most people
thought that women didn’t need an education and that they should be satisfied
by getting married and having children.
I was preparing to get married and my
father was trying to practice the polka, a must at any Ukrainian wedding. But
he couldn’t do it! He had lost the mobility（活动能力）in his leg and suffered a brain tumor（瘤）. He was forced to retire as
a result of paralysis（瘫痪）of his right arm and leg. Dad had always worked two jobs and spent
his spare time working around the house. Now his life came to a sudden stop.
Yet never once did he complain. He bought rubber balls and spent his days
trying to regain his hand mobility by squeezing those balls over and over.
After his second brain operation, he
chatted pleasantly in the hospital room until a nurse flew into the room,
waving her finger at me, and yelling, “You’d better tell your father to stay in
bed. He is paralyzed and will never walk again. I am sick of picking him up and
you’d better warn him to stay put!” My father smiled. He spent a great deal of
time on the floor that year, but he eventually got up and walked.
My father lived nineteen more years after
that second brain operation. He bought himself a motorized scooter（单脚滑行车）and spent years moving
around the streets of Philadelphia. He was proud, free and always smiling.
56.In what way was the father different
from most other people in his time?
A. He succeeded immigrating to the
US.&&&&&
B. He learned the new language easily and
quickly.
C. He achieved his life goal by working as
a barber.&&&
D. He tried to offer his daughters the
education chance.
57.&& The underlined word “polka”
in Paragraph 2 probably refers to ________.
A. a song &&& B. a
dance&&&&&&&& C. a rubber
ball&&&&&& D. a new language
58.&& The author’s father played
with rubber balls to ________.
A. kill his too much spare
time&&&& B. reduce his work pressure
C. get his hand mobility
back&&&&&& D. recover from the brain tumor
59.&& What can we learn from the
passage?
A. Love can create
wonders.&&&&&&&&& B. Failure is
the mother of success.
C. Father’s love is the most
valuable.&& D. Never give up your life and dream.
科目：高中英语
来源：四川省2010届高三考前冲刺考试英语试题
题型：阅读理解
第二部分：阅读理解（第一节20小题，第二节5小题；每小题2分，满分50分）
第一节：阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项，并在答题纸上将该选项标号涂黑。
Compassion is a desire within us to help others. With effort, we
can translate compassion into action. An experience last weekend showed me this
is true. I work part-time in a supermarket across from a building for the
elderly. These old people are our main customers, and it’s not hard to lose
patience over their slowness. But last Sunday, one aged gentleman appeared to
teach me a valuable lesson. This untidy man walked up to my register(收款机) with a box of biscuits. He said he was
out of cash(现金), had
just moved into his room, and had nothing in his cupboards. He asked if we
could let him have the food on trust. He promised to repay me the next day.
&&& I couldn’t help staring at him. I wondered what
kind of person he had been ten or twenty years before, and what he would be
like if luck had gone his way. I had a hurt in my heart for this kind of human
soul, all alone in the world. I told him that I was sorry, but store rules
didn’t allow me to do so. I felt stupid and unkind saying this, but I valued my
job.
&&& Just then, another man, standing behind the
first, spoke up. If anything, he looked more pitiable. “Charge it to me,” was
all he said.
&&& What I had been feeling was pity. Pity is soft
and safe and easy. Compassion, on the other hand, is caring in action. I
thanked the second man but told him that was not allowed either. Then I reached
into my pocket and paid for the biscuits myself. I reached into my pocket
because these two men had reached into my heart and taught me compassion.
1. The aged gentleman who wanted to buy the biscuits ______.
& A. promised to obey the store rules&&&&&&&&&&&&&&&&
B. forgot to take any
money with him
& C. hoped to have the food first and pay later&&&&&&&&&&
D. could not afford
anything more expensive
2. Which of the following best describes the old gentleman?
& A. kind and lucky&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&& B.
poor and lonely
& C. friendly and helpful&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&& D.
hurt and disappointed
3. The writer acted upon the store rules because ______.
& A. he wanted to keep his present job&&&&&&&&&&&&&&&&&&&&&
B. he felt no pity
for the old gentleman
& C. he considered the old man dishonest&&&&&&&&&&&&&&&&&
D. he expected
someone else to pay for the old man
4. What does the writer learn from his experience?
& A. Wealth is more important than anything else.&&&&&&&&&&&&
B. Helping others is
easier said than done.
& C. Experience is better gained through practice.&&&&&&&&&&&&
D. Obeying the rules
means more than compassion.
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40．在试述正常人类G显带核型分析中识别各号染色；41．简述有丝分裂过程；答：有丝分裂过程是一个复杂的连续的动态变化过程，；①前期：核内染色质螺旋化逐渐缩短变粗形成染色体，；②中期：随着染色体螺旋化程度增高，染色体更缩短变；③后期：每条染色体着丝粒复制纵裂为二，原来构成一；④末期：集中于两极的两组染色体逐渐解旋、变细长成；42．什么是减数分裂？简述减数分裂过
40． 在试述正常人类G显带核型分析中识别各号染色体的最主要特点。 答：结合人类G显带核型分析实验，参考主教材复习正常人类G显带核中各号染色体识别的最主要特点，只要根据最突出的特点在正常人G显带核型中认出是第几号染色体即可。41． 简述有丝分裂过程。答：有丝分裂过程是一个复杂的连续的动态变化过程，根据光镜下所见的形态学特征分为四个时期：前期、中期后期和末期。①前期：核内染色质螺旋化逐渐缩短变粗形成染色体，每条染色体由两条染色单体构成，核仁、核膜消失。②中期：随着染色体螺旋化程度增高，染色体更缩短变粗，形成光镜下最清晰、最易分辨、形态最典型的染色体，染色体排列在细胞中央赤道面上形成赤道板，着丝粒与纺锤丝微管相连。③后期：每条染色体着丝粒复制纵裂为二，原来构成一条染色体的两条染色单体成为具独立结构的两条相同的染色体，此时，籍纺锤丝的牵引，两组数目、形态结构相同的染色体分别移向两极。④末期：集中于两极的两组染色体逐渐解旋、变细长成为染色质，核膜形成，核仁重新出现，形成两个子细胞核。同时细胞质分裂，最后形成两个子细胞，完成了有丝分裂的全过程。42． 什么是减数分裂？简述减数分裂过程。答：减数分裂又称成熟分裂，是精子和卵细胞发生过程中进行的一种特殊的有丝分裂，它只发生在精子和卵细胞发生的成熟期。二倍体细胞经过连续两次分裂，但DNA只复制一次，即染色体只复制一次，因此子细胞中染色体数目减半，形成单倍体。减数分裂过程：减数分裂Ⅰ
由初级精母或初级卵母细胞（2n）形成次级精母或次级卵母细胞（n）①前期Ⅰ：染色体变化复杂，延续时间特别长。根据染色体形态变化的特点，可分为5个时期：细线期、偶线期、粗线期、双线期和终变期。减数分裂的复杂变化，主要表现为前期Ⅰ的复杂变化。细线期：染色体呈细线状。此期大部分DNA分子已在减数分裂Ⅰ前的间期即间期Ⅰ复制完成。故此时每条染色体已由两条姐妹染色单体构成，但光镜下不能识别。偶线期：同源染色体互相靠拢，在各相同的位点上准确地配对，这现象称为联会，联会时在同源染色体之间沿其长轴形成联会复合体。联会的结果，每对联会在一起的同源染色体形成一个二价体，有几对染色体的细胞，就形成几个二价体。人体细胞23对染色体形成23个二价体。联会是减数分裂特有的现象，它是同源染色体之间发生交换的必要条件。粗线期：二价体螺旋化缩短变粗，在光镜下可见每条染色体由两条姐妹染色单体构成，因此，每个二价体具有一对同源染色体，包括四条染色单体，称为四分体。在四分体中同源染色体的染色单体之间互称为非姐妹染色单体。此期，非姐妹染色单体之间有时可看到交叉现象，表明在它们之间已发生了相对应片段的交换，这是遗传物质互换重组的基础。交叉是同源染色体非姐妹染色单体之间发生了交换的一种表现。双线期：二价体进一步螺旋化而缩短增粗，联会复合体解体，联会的同源染色体互相排斥而开始分离，交叉点逐渐端化。终变期：染色体继续螺旋化而变得更粗更短。交叉继续端化而数目减少，核仁、核膜消失。②中期Ⅰ
各二价体排列在细胞中央赤道面上，形成赤道板，纺锤丝微管与二价体着丝粒相连，同源染色体的着丝粒朝向两极。③后期Ⅰ
随纺锤丝的牵引，二价体中的两条同源染色体彼此分离 ，分别移向细胞的两极。每条染色体含有两条姐妹染色单体，称为二价体。当同源染色体分离并移向两极的同时，非同源染色体（即不同对染色体）之间互相独立，即可随机组合（自由组合），移向细胞两极，两对同源染色体可有232=4种组合方式，三对同源染色体可有2=8种组合方式，人有23对染色体23即可有2=8388608种组合方式。④末期Ⅰ
各二分体移至两极后，染色体逐渐解旋、伸展、核膜、核仁重新出现，随着细胞质的分裂形成两个子细胞，即次级精母细胞或次级卵母细胞和极体。每个子细胞中染色体数目已减半，为单倍体（n）。细胞中具有几个二分体，即为几个已复制的染色体。减数分裂Ⅰ结束后经过短暂的间期Ⅱ进入减数分裂Ⅱ或不经间期Ⅱ直接进入减数分裂Ⅱ，在这过程中不再进行DNA复制。减数分裂Ⅱ①前期Ⅱ
此期时间较短，二分体凝缩，核仁核膜消失。②中期Ⅱ
各二分体排列在细胞中央赤道面上，形成赤道板，纺锤丝微管与着丝粒相连。③后期Ⅱ
各二分体的着丝粒分裂，每条二分体形成两条单分体，即成为两条染色体，随纺锤丝牵引分别移向两极。④末期Ⅱ
各单分体染色体移至两极后，解旋、伸展、又形成染色质，核膜、核仁重新出现，分别形成两个子细胞核，然后，细胞质分裂，形成两个子细胞，即精细胞和卵细胞和第二极体，细胞内只含23条染色体为单倍体（n）。至此减数分裂过程结束，一个初级精母细胞（2n）形成四个精细胞（n），一个初级卵母细胞（2n）形成一个卵细胞（n）和三个极体（n）。 43．某生物体细胞中具有两对染色体，其中一对为中着丝粒染色体，另一对为近端着丝粒染色体，试以模式图方式绘出：书p57页⑴有丝分裂中期图⑵第一次减数分裂中期（中期Ⅰ）图⑶第二次减数分裂中期（中期Ⅱ）图答：⑴图示4条染色体排列在细胞中央赤道面上⑵图示两个二价体在细胞中央赤道面的排列情况；有几种可能排列情况。 ⑶图示两个二分体在细胞中央赤道面的排列情况。43． 导致多倍体产生的机理有哪些？答：一般认为多倍体形成的机理有双雄受精、双雌受精和核内复制。双雄受精即同时有两个精子进入卵细胞位卵子受精。由于每个精子带有一个染色体组，所以它们与卵细胞中原有的一个染色休组共同形成了三倍体的受精卵。
双雌受精即即含有一个染色体组的精子与含有两个染色体组的异常卵细胞受精，即形成三倍体的受精卵。核内复制是指在一次细胞分裂时，DNA复制了两次，每个染色体有四条单体，这样形成的两个子细胞那是四倍体。综上所述，三倍体形成的原因可能是由于双雌受精和双雄受精，核内复制可以形成四倍体细胞。44．21三体综合征的核型有哪些？主要的临床表现是什么？答：21三体综合征又叫做先天愚型、Down综合征，是儿科中为常见的一种染色体病。本病分成三种类型。完全型21三体，简称21三体型。患者比正常人多一条完整的21号染色体，其核型为47，XX(XY)，+21。易位型21三体，一般可由于母亲发生染色体14／21平衡易位，而导致该个体的子代出现21三体综合征的患儿，患儿的核型为46，XY(XY)，―14，+t（14q21q）。嵌合型21三体，即在某一个体体内同时含有正常的二倍体细胞系和异常的21三体型细胞系，核型通常为46，XX（XY）/47，XX（XY），+21。临床表现：智力低下是本病的主要症状。先天愚型的患者身体发育迟缓，大多伴有特殊面容，包括：眼距宽、外眼角上斜、塌鼻梁、口常半开、流涎、舌大并常外伸，又称为“伸舌样痴呆”。患儿常常合并重要脏器的畸形，如先天性心脏病、十二指肠闭闭锁等，多在早期夭折。男性患者可有隐睾，女性患者通常无月经来潮。在本病的患者中，通贯掌出现的频率较高，且第五指只有一条指褶纹。45． 写出先天性睾丸发育不全综合征的核型及主要临床表现。答：先天性睾丸发育不全综合征又称作Klincfelter综合征或XXY综合征。核型可有多种改变，其中以47，XXY最典型；其他还有如47，XXY/46，XY等。本病的主要临床表现是男性不育、第二性征发育不明显并呈女性化发展，以及身材高大等。在青春期之前，患者没有没有明显的症状；青春期后，逐渐出现睾丸小、阴茎发育不良、精子缺乏、乳房发育女性化、男性第二性征发育不良，可伴随发生先天性心脏病等，部分病人有智力障碍。 什么是脆性X染色体综合征？其主要临床表现是什么？46． 什么是脆性X染色体综合征？其主要临床表现是什么？答：如果一条X染色体Xq27―Xq28之间呈细丝样结构，并使其所连接的长臂末端形似随体，则这条X染色体就被称作脆性X染色体。若女性个体的细胞中带有一条脆性X染色体，一般没有表型的改变，为携带者；若是男性个体的细胞中带有脆性X染色体，则会表现出的一系列临床改变即为脆性X综合征。脆性X综合征的主要临床表现为中重度的智力低下、语言障碍、性格孤僻、青春期后可见明显大于正常的睾丸，伴有特殊面容――长
脸、方额、大耳朵、嘴大唇厚、下颌大并前突、巩膜呈淡蓝色。47．倒位染色体的携带者为什么会出现习惯性流产的现象？答：由于倒位发生时一般没有遗传物质的丢失，所以倒位携带者本身并无表型的改变，但在减数分裂同源染色体配对联会时，由于基因顺序的颠倒，这一条倒位的染色体无法与另一条正常的染色体正常配对，而形成了一个特殊的结构――倒拉环。如果这时同源染色体在倒位环内发生重组，则会产生四种配子(参阅主教材图P91页)。这四种配子分别与正常异性配子结合时，就会有不同的情况产生。一种配子是完全正常的，与正常配子受精所形成的受精卵也是完全正常的；另一种配子含有一条倒拉染色体，受精后发育为倒位染色体的携带者；而其余两种配子都含有染色体部分片段的缺失和重复，所以与正常配子结合后，可形成部分单体、部分三体的胚胎，这种胚胎常发生自然流产。基于以上原因，倒位染色体的携带者在生育子女时常常会发生自然流产的情况。48．某一外表正常的妇女，经染色体检查发现所有被检的核型中都具有一条臂间倒位的2号染色体。其断裂点分别为2p21和2Q31，其它染色体都正常。请回答：①根据ISCN（1978）的简式和繁式的描述方法，写出该妇女的异常核型。②如该妇女与正常男性婚配，其后代可能出现哪些情况，请绘图分析说明。答：①简式：46，XX，inv（2）（p21q31）繁式：46，XX，inv（2）（pter→p21：：q31→p21：：q31→qter）②当她与正常男性结婚后，其后代可有完全正常、倒位携带者及自然流产、早产、死胎等情况。由于在她进行减数分裂的过程中，倒位的染色体不能以正常的方式和与其同源的染色体进行联会，所以形成了一个特殊的结构――倒拉环（参阅主教材图P93页）如果不发生同源染色体的重组，则产生两种配子：正常的和倒位的。这两种配子与正常配子结合后，将分别发育成正常胚胎和携带有倒拉染色体的胚胎。若环内发生同源染色体的重组，则会产生四种配子。这四种配子与正常配子结合后，其一，发育与正常胚胎；其二，发育成倒位携带者；余者均为流产、早产或死胎等情况。 49．一对外表正常的夫妇，因习惯性流产来遗传咨询门诊就诊，染色体检查结果男方核型为46，XY，女方核型为46，XX，t（4；6）（4pter→4q35：：6q21→6qter；6qter→6q21：：4q35→4qter）。试问：①女性核型有何异常；②分析这对夫妇发生习惯性流产的原因。答：①该女性4号和6号染色体之间发生了相互易位，两条染色体上的断裂点分别为长臂3区5带和长臂2区1带。②由于该女性带有4号、6号染色体部分片段相互易位后形成的衍生染色体，所以在减数分裂时，衍生染色体不能以正常的方式与完整的4号、6号染色体进行联会。此时会形成一个特殊的结构――四射体，当四射体内的染色体发生重组时，可形成几种配子。在这几种配子中，一种是正常的，一种是带有两条易位染色体的，余者均含有部分片段的单体型和部分片段的三体型。由第一种配子受精将发育成完全正常的胚胎；第二种配子受精将发育成一个易位染色体的携带者；余者皆由于含有部分片段的单体型和部分片段的三体型而率为1／2。．50．豌豆红花基因(R)对白化基因(r)为完全显性，纯种红花豌豆和纯种豌豆杂交，请问：(1)F1代基因型和表现型如何?(2)F1代自交所产生的F2代表现型、基因型及其分离比是什么?(3)F2代显性形状和隐性性状山现的概率是多少?(4)F2代显性性状中，杂合体出现的概率是多少？答：(1)F1代基因为Rr，表现型均为红花豌豆；(2)F2代表现型是红花豌豆和白花豌豆，分离比为3：I，基因型为RR、Rr和rr，分离比为RR：Rr：rr＝1：2：1；(3)F2显性性状出现的概率为3／4，隐性性状出现的概率为1／4；(4)F2代显性性状中，杂合体出现的概率为2／3。51．雄果蝇的基因型为BbVv，B和V位于同一条染色体上，b和v位于另一条染色体上，它们之间无交换，请问：（1）它能产生多少种雄配子？（2）配子的类型是什么？（3）符合基因的什么规律？答：（1）它能产生两种雄配子；(2)配子类型是Bv和bv；(3)符合完全连锁遗传。52．雌果蝇的基因类型为BｂVｖ，B和V位于同一染色体上，ｂ和ｖ位于另一条染色体上，它们之间有交换，请问（1）它能产生多少种雌配子？（2）雌配子的类型是什么？（3）符合基因的什么规律？答：(1)它能产生四种雌配子；(2)雌配子的类型是：BV、bv、Bv、ｂV；(3)符合不完全连锁遗传。53．丈夫A型血，他的母亲是O型血；妻子为AB型血，问后代可能出现什么血型，不可能出现什么血型。答：由题意可知：丈大的基因型为IAｉ，妻子的基因型 IAIB，根据分离定律和共显性的原理，这对夫妇的后代可能出现A型、B型、AB型，不可能出现O型。54．母亲O型血，父亲B型血，有一个孩子是O型血，问：（1）第二个孩子为O型血的概率是多少？2第二个孩子是B型血的概率为多少？ 答：由题意可知父亲的基因型为IBi，母亲的基因型为ii，根据分离定律的原理(1)第二个孩子是O型血的概率为1／2；(2)第二个孩子是B型血的概率为1/2。55．短指症是一种常染色体显性遗传病，请问：（1）病人(Aａ)与正常人生下短指症的比例是多少？（2）如果两个短指症的病人（Aa）结婚，他们的子女的患短指症的比例是多少？答：(1)1/2；(2)3/4。56．父亲是红绿色盲患者，母亲外表正常，生下一个女儿是红绿色盲，一个男孩是甲型血友病（提示：色盲基因用ｂ表示，血友病基因用ｈ表示，两致病基因均在X染色体上如不考虑交换）问：（1）他们所生的女孩中，色盲的概率是多少？正常的概率是多少？血友病的概率是多少？（2）他们所生的男孩中，色盲的概率是多少？血友病的概率是多少？正常的概率是多少？答：红绿色盲和甲型血友病都属于X连锁隐性遗传病。由题意可知，母亲既是红绿色盲基因携带者也是甲型血友病携带者，有儿子是甲型血友病而视B觉正常可知，两致病基因不在同一条染色体上。因此双亲的基因型是：XB
XHh×Xb H Y，如不考虑交换，在这样的婚配形式下，他们所生的女孩中色盲的概率为50％，正常的概率为50％，血友病的概率为0。他们所生的男孩中色盲的概率是50％，血友病的概率为50％，正常的概率为0。57．一个色觉正常的女儿，可能有一个色盲的父亲吗？可能有色盲的母亲吗？一个色盲的女儿，可能有色觉正常的父亲吗？能有色觉正常的母亲吗？答：一个色觉正常的女儿，可能有一个色盲的父亲，也可能有色盲的母亲；一个色盲的女儿，不可能有色觉正常的父亲，可能有色觉正常但是色盲基因携带者的母亲58．人类的指关节僵直症是有一个显性基因引起的，外显率75%，问：（1）如果杂合体患者与正常个体婚配，在他们的子女中患这种病的比例是多少？（2）杂合体患者之间结婚，子女患这种病的比例是多少？答：(1)设致病基因用R表示，杂合体患者基因型为Rr，正常人的基因型为rr，婚配后预计生患儿的风险为1/2，因为该病的外显率为75％，所以婚配Ⅱ
2 答：Ⅱ1和Ⅱ2再生孩子的患病风险为：80%×1/2=40%。
60．下面是一个视网膜母细胞瘤（不完全外显）的系谱，假如外显率为90%， 问Ⅱ1和Ⅱ2婚配生下患儿的风险 Ⅰ
○□2○3 Ⅲ1答：：因为Ⅱ1和Ⅱ2未生下患者，所以Ⅱ2的基因型不能肯定，需按照Bayes定律计算Ⅱ2 是杂合体的概率。概
Ⅱ2是杂合体
Ⅱ2是纯合体前概率
1/2条件概率
0.05/0.05+0.5=0.09
0.5/0.05+0.5=0.91Ⅱ2是杂合体的概率为0.09，所以Ⅱ1和Ⅱ2婚配生下患者的风险是： 23456Ⅲ
A是aa前概率
1/2条件概率
0.45/0.45+0.5=0.4737
0.5/0.45+0.5=0.5267 所以系谱中患者的正常同胞是杂合体的风险为47.3%，故系谱中正常同胞将12 Ⅱ
4答：白化病是一种常染色体隐性遗传病，Ⅱ1为患者（aa），Ⅰ1为肯定携带者；I2有1/2的可能性为携带者，Ⅱ2是携带者的前概率是1/4，Ⅱ2不是携带者的前概率为3/4，Ⅱ1和Ⅱ2婚后已生出3个并不白化的孩子，如果Ⅱ2是携带者，生三个孩子都不白化的概率为（1/2）3，如果Ⅱ2不是携带者，生出三个孩子均正常的概率为13依此求出联合概率和后概率。 概
Ⅱ2是ＡＡ前概率
3/4条件概率
（1/2）3＝1/8
1/4×1/8＝1/32
1/32/（1/32＋3/4）＝1/25
3/4/（1/32+3/4）＝24/25
Ⅱ2是杂合体的风险为1/25，所以Ⅱ1和Ⅱ2再生孩子是白化病的风险是：1/25×1/2＝1/50。63．从遗传学角度解释以下情况①双亲全为茸哑,但其后代正常；②双亲全正常,其后代出现聋哑；③双亲全为聋哑,其后代全为聋哑. 答①遗传的异质性，如aaBB×Aabb→AaBb，子代每一对致病基因都未达到隐性纯合。②双亲均与聋哑病基因携带者，如Aa与Aa，子代可有1/4达到aa纯合而发病。③双亲全为同一位点隐性致病基因纯合子患者，所以子代全发病。64．估计多基因遗传病发病风险时，应综合考虑哪儿方面的情况？ 答：首先，应注意亲属级别，当估计患者一级亲属发病风险应用Edward公式时，要符合公式要求的条件：即群体发病率在0.1%～1%之间，遗传率为70%～80%。同时随着亲属级别的降低，发病风险呈迅速降低趋势；第二，要考虑多基因的累加效应，如一对夫妇生育的患儿越多，则说明这对夫妇携带的致病微效基因越多，因而他们的易患性更接近阈值，再次生育时复发风险增高。如果患儿的病情严重，也说明相同的情况。因此，当以一对夫妇生育了两个患儿或所生患儿病情严重，则再发风险增高；第三，要注意某种多基因遗传病的发病率是否存在的性别差异，如果确有性别差异，则发病率高的性别其阈值低，已发病的患者易患性也较低，因此，他的子女再发风险较低。相反，发病率低的性别其阈值高，已发病的患者易患性必然很高，其子女再发风险较高。以上几方面的情况应全面综合考虑，作出切合实际的估计。65．什么是遗传平衡定律？影响群体遗传结构的因素有哪些？65．什么是遗传平衡定律？影响群体遗传结构的因素有哪些？答：当一个群体符合下列条件时，①群体很大或者无限大，②群体内个体进行随机交配，③没有突变发生，④没有选择，⑤没有大规模迁移，⑥没有遗传漂变，群体的基因频率将代代相传，保持不变，而且，不论群体起始基因频率如何，经过一代随机交配后，群体的基因频率将达到平衡，只要平衡条件不变，基因型频率亦代代保持不变，这是群体的遗传平衡定律。影响群体遗传结构的因素包括突变，选择，迁居（迁移）遗传漂变，近亲婚配。66．研究医学群体遗传学有何意义？答：通过医学群体遗传学的研究，可使人们了解人类遗传病的发病率、遗传病的传递方式、致病基因频率及致病基因频率的变化规律，为认识某些遗传病的产生原因和遗传咨询提供理论依据，为遗传病的预防、监测以及治疗提供必要的资料。所以医学群体遗传学研究对减少遗传病患儿的出生，降低遗传病的群体发病率，提高人类的遗传素质具有重要意义。67．一个大群体中，存在AA，Aa，aa三种基因型，它们的频率分别为0.1，0.6，0.3。⑴这个大群体中等位基因的频率是多少？⑵随机交配一代后，等位基因频率和基因型频率是多少？答：⑴因为，D=0.1，H=0.6，R=0.3，所以，A基因的频率
p=0.1+1/2×0.6=0.4a基因的频率q=0.3+1/2×0.6=0.6⑵随机交配一代后，基因频率保持不变，即p1=0.4，q1=0.6。随机交配后，该群体将达到平衡状态，所以AA、Aa、aa三种基因型频率22分别为：D1=p=0.16，H=2pq=2×0.4×0.6=0.48,R=q=0.36。68．MN血型基因频率，在白人中，M基因为0.54，N基因为0.46；在澳大利亚人群中，M基因因为0.18，N基因为0.82，假如对白人男性与澳大利亚女性结婚所生的1000个后代进行调查，⑴M型、MN型、N型各有多少人？⑵后代的基因频率是多少？答：⑴设白人的M，N基因频率分别为p1，q1；澳大利亚人的M，N基因频率分别为p2，q2，那么，白人男性与澳大利亚女性结婚，精卵结合类型及频率为下表：MM的频率为p1p2=0.54×0.82=0.0972MN的频率为p1q2+p2q1+0.54×0.82+0.18×0.46=0.5256NN的频率为q1q2=0.46×0.82=0.37721000个后代中M型的人数为97.2；MN型的人数为525.6；N型的人数为377.2⑵白人男性与澳大利亚女性结婚所生后代的各基因频率为：M基因频率为0.×0.N基因频率为0.×0.69．酶基因缺陷如何引起各种代谢紊乱并导致疾病？答：人体正常代谢是由许多代谢反应交织成网而形成的平衡体系，每步反应需要酶的调节。如果酶基因缺陷会引起酶缺乏或活性异常，进而影响相应的生化过程，引发连锁反应，打破正常的平衡，造成代谢紊乱而致病。酶基因缺陷具体可引起下列代谢异常：①代谢终产物缺乏；②代谢中间产物积累；③代谢底物积累；④代谢副产物积累⑤代谢产物增加⑥反馈抑制减弱等等。当这些紊乱严重时，便表现为疾病。70．简述葡萄糖-6-磷酸脱氢酶缺乏症的主要临床症状及其分子机理。 答：该病由于葡萄糖-6-磷酸脱氢酶（G6PD）基因（Xq28）缺陷，导致G6PD缺乏所引起。患者平时无明显症状，但吃了蚕豆或一些药物（解热镇痛类、喹啉类、磺胺类等等）后，出现血红蛋白尿、黄疸、贫血等急性溶血反应。正常代谢中，G6PD催化葡萄糖-6-磷酸脱氢并生成NADPH（还原型辅酶Ⅱ）。后者使谷胱甘肽GSSG转变成还原型谷胱甘肽GSH。足量的GSH可解除机体在氧化还原过程或氧化性药物作用下产生的H2O2，消除其毒性作用。若G6PD缺乏，使NADPH减少，导致GSH不足。服用某些药物或代谢所产生的H2O2，会破坏GSH并积累，过多的H2O2可氧化血红蛋白，使其变性后沉降于红细胞膜上，同时，H2O2还氧化红细胞膜上的蛋白，最终导致红细胞变形能力下降而膜脆性增加，挤压易破裂，引发急性溶血反应。71．以异烟肼灭活为例，简述药物反应的多样性及其遗传基础，应如何合理用药？答：人类的药物反应存在个体差异，这主要是由于不同个体的遗传背景（基因型）所决定。例如，抗结核药异烟肼可通过乙酰化而灭活，乙酰化酶活性高低决定其灭活的速度，该酶由常染色体上的一对基因控制。人群中存在着RR、Rr、rr不同基因型的个体，乙酰化酶活性分别为高、中、低，所以RR型个体为快灭活者，Rr型为中等速度灭活者，rr型为慢灭活者，异烟肼在他们体内的反应（疗效、副作用）不尽相同。如果每天服药，快、慢灭活者疗效一致；若每周服药1～2次，则快灭活者疗效较差。从毒副作用考虑，长期服用此药，慢灭活者易积累异烟肼，后者灭活维生素B6，引起多发性神经炎。快灭活者由于乙酰化快，产生的乙酰化异烟肼在肝中进一步分解为异烟酸和乙酰肼，后者损害肝脏致肝炎。因此，服用异烟肼时应加维生素B6，并注意掌握用药的个体化原则，尽量减少毒副作用而达到治疗的目的。72．举例说明肿瘤的发生与遗传因素有关。答：某些肿瘤在不同人种中的发病率高低不同。如中国人的鼻咽癌居世界各民族的首位，发病率比印度高30倍，比日本人高60倍，而且这发病率不因包含各类专业文献、文学作品欣赏、应用写作文书、生活休闲娱乐、中学教育、幼儿教育、小学教育、外语学习资料、行业资料、遗传学问答题(小)36等内容。　
　遗传学试题库(一)一、名词解释:(每小题 3 分,共 18 分) 1、 外显子 2、复等位基因 3、F 因子 4、母性影响 5、伴性遗传 6、杂种优势 二、填空题:(... 　遗传学试题以及答案整理_理学_高等教育_教育专区。遗传学试题库( 遗传学试题库(一)一、名词解释:(每小题 3 分,共 18 分) 名词解释: 1、外显子:把基因内部... 　9页 免费 遗传学问答题(1) 4页 免费 遗传学问答题(小) 12页 1下载券 谈谈遗传学中若干基本问... 4页 免费 遗传学的问题 1页 免费喜欢此文档的还喜欢 ... 　《遗传学》试题及答案_理学_高等教育_教育专区。《普通遗传学》试题 一、名词解释(共 10 小题,每小题 2 分,共 20 分) 1 连锁遗传图:描述基因在染色体上的... 　遗传学试题库及答案 (12套 )遗传学试题库及答案 (12套 )隐藏&& 遗传学试题库及答案 (12 套 ) 遗传学试题库(一) 遗传学试题库( 一、名词解释:(每小题 ... 　遗传学试题_农学_高等教育_教育专区。遗传学考试选择题(每小题 2 分,共 30 分) 在高等植物的细胞质中,除质体外, A. 核糖体 B. 内质网 C. 线粒体 中也... 　遗传学课程组 命题共 3 页 考试说明:请将考试答案全部做在答题纸上,考试时间 120 分钟 一 、名词解释: (本大题共 10 小题,每小题 1 分,共 10 分) 1... 　遗传学试题一试卷 三、填空题(共 10 分) 1、三价体存在于 、 等非整倍体...倍性的;小核主 43、由于倒位环内的交换产生___和___,导致配子的死亡。... 　26.基因漂移 答案:由误差引起的小群体内基因频率随机变化的现象 27.Heredity ...9 简述独立分配规律的细胞学基础。 四、问答题 1 试述分子遗传学及经典遗传学...}