题目内容

【题目】人类多指（T）对正常指（t）为显性，皮肤白化（a）对正常（A）为隐性，都在常染色体上，且都独立遗传。一个家庭中，父亲是多指，母亲正常，他们有一个白化病和手指正常的女儿，则再生一个正常的儿子和只有一种病的儿子的几率分别是

A．1/2，1/8 B．1/4，1/4

C．3/8，1/2 D．3/16，1/4

【答案】D

【解析】

试题分析：父亲是多指，母亲正常，他们有一个白化病和手指正常的女儿，可以推知双亲基因型分别是父亲AaTt、母亲是Aatt，所以，对于白化病子代遗传情况为：Aa×Aa→3/4正常、1/4白化；对于多指的子代遗传情况为：Tt×tt→1/2多指、1/2正常。所以生一个正常的儿子概率是3/4×1/2×1/2=3/16；只有一种病的儿子的几率是（3/4×1/2+1/4×1/2）×1/2=1/4。综上所述，D正确。

练习册系列答案
相关题目

【题目】阅读下面的短文，根据短文内容完成下表，注意一空一词。

Attitude is an internal state that influences the choices of personal action made by the individual. Some researchers consider that attitudes come from differences between beliefs and ideas; others believe that attitudes come from emotional states. Here, we focus on the effects of attitudes upon behavior, that is, upon the choices of action made by the individual.

The kinds of actions taken by human beings are obviously influenced greatly by attitudes. Whether one listens to classical music or rock, whether one obeys the speed limit while driving, whether one encourages one’s husband or wife to express his or her own ideas—all are influenced by attitudes. These internal states are acquired throughout life from situations one is faced with in the home, in the streets, and in the school.

Of course, the course of action chosen by an individual in any situation will be largely determined by the specific facts of that situation. An individual who has a strong attitude of obeying laws may drive too fast when he is in a hurry and no police cars in sight. A child who has a strong attitude of honesty may steal a penny when she thinks no one will notice. But the internal state which remains unchanged over a period of time, and which makes the individual act regularly in a variety of situations, is what is meant by an attitude.

Attitudes are learned in a variety of ways. They can result from single incidents, as when an attitude toward individual’s experiences of success and pleasure, as when someone acquires a positive attitude toward doing crossword puzzles by being able to complete some of them. And frequently, they are learned by copying other people’s behavior, as when a child learns how to act toward foreigners by observing the actions of his parents. Regardless of these differences, there is something in common in the learning and modification of attitudes.

Title: Nature of Attitude

Attitude and its influence

Contexts

【1】 _______of attitude

It is an internal state that influences the choices of personal action and come from different experience in one’s life. Others believe that attitudes come from 【2】 ___________.

The effect of attitudes on human beings 【3】 _______

Common activities in daily life are the 【4】 ________ of the internal state.

【5】 _____ of a situation may influence an individual’s action

A strong attitude may 【6】 _______ over a period of time, which helps to form a 【7】 ______. But due to some special occasion, people may be engaged in what they are not 【8】 ______ to do.

How attitude 【9】 ______ into being.

It can be learnt from experience and mostly by 【10】 _________.

【题目】科学研究表明，月球上有丰富的He资源，可开发利用作未来的新型能源。

(1) He的中子数是________，He与He互称为________。

(2)α粒子是带有2个单位正电荷、质量数为4的原子核，由此推断α粒子含有________个质子和________个中子。

(3)在He、He两种核素中，原子核内的中子数之差为________，与α粒子有相同质子数和中子数的是________。

【题目】七选五

根据短文内容，从短文后的七个选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Happy birthday! Do birthdays really make people happy? 1 Birthdays celebrate the day when we were born. Besides, that extra candle on the cake suggests another year of growth and maturity(成熟) — or so we hope. We all like to imagine that we are getting wiser and not just older. Most of us enjoy seeing the wonder of growth in others as well. For instance, seeing our children develop and learn new things makes us feel proud. For Americans, like people in most cultures, growing up is a wonderful process. But growing old? 2

Growing old is not exactly for people in youth-oriented American culture. 3 As the old saying goes, ＂You’re young as you feel.＂ Older people joke about how many years young they are, rather than how many years old. People in some countries value the aged as a source of experience and wisdom. But Americans seem to favor those that are young, or at least ＂young at heart＂.

Many older Americans find the ＂golden years＂ to be anything but golden. Economically, ＂senior citizens＂ often struggle just to get by. Retirement at the age of 65 brings a sharp decrease in personal income. Social security benefits usually cannot make up the difference. Older people may suffer from poor nutrition, medical care, and housing. 4 American sociologist Pat Moore once dressed up like an older person and wandered city streets. She was often treated rudely — even cheated and robbed. However, dressed as a young person, she received much more respect.

5 Why? People are living longer. Fewer babies are being born. And middle-aged ＂baby boomers＂ are rapidly entering the group of the elderly. America may soon be a place where wrinkles(皱纹) are ＂in＂. Marketing experts are already noticing this growing group of consumers.

A. Of course they do.

B. That is a different story.

C. Most people in America like the young.

D. Some even experience age discrimination(歧视).

E. The population in America grows larger every year.

F. Most Americans like to look young, act young and feel young.

G. Unfortunately, the elderly population in America is increasing fast.

【题目】B

April 23 marks the 400th anniversary of William Shakespeare’s death. Organizations in Britain have planned numerous events to honor him.

In Stratford-upon-Avon, his birthplace, the tourism organization has a great number of free events, including performances of Shakespeare’s plays, and a dazzling fireworks display. And the BBC is broadcasting a live show from Stratfore-upon-Avon, celebrating Shakespeare’s widespread influence on the world. In England’s capital, the London Shakespeare Centre and King’s College London are holding a series of public performances, exhibitions and activities. It isn’t just England that honors the anniversary of the death of this extraordinary writer. In Washington, D. C., the Folger Shakespeare Library, which houses the world’s largest collection of documents relating to William Shakespeare, is displaying a series of exhibitions.

Shakespeare is probably the most famous author who ever lived and is considered a genius by most. He wrote around 37 plays and 154 sonnets(十四行诗), and his work has been translated into over one hundred languages! He penned beautiful metaphors(暗喻), serious dramas and amusing tales.

Shakespeare also invented many new terms and phrases. If someone’s behavior suggested they were not being honest and should not be trusted, Shakespeare called their actions suspicious. If someone was being silly and perhaps looking like a fool, Shakespeare found their actions laughable. And Shakespeare called people who offered their opinions on the quality of something critics. Today, for instance, food critics and film critics give audiences their opinions of food and film. The familiar phrase “break the ice”/span> comes from Shakespeare’s play The Taming of the Shrew. The “ice is broken” when a difficult conversation or meeting is calmed by some basic introduction, such as a simple game. More common words coined by Shakespeare include road, gossip, lonely, bump and hurry.

Four hundred years after his death, Shakespeare surely lives on, in everyday speech, as the most famous writer of all time!

【1】The main idea of the text is _____.

A. the 400th anniversary of Shakespeare’s death

B. the influence Shakespeare has on English

C. the achievements of William Shakespeare

D. Shakespeare’s colorful and fruitful life

【2】 Shakespeare is honored in the following ways except_________.

A. a great number of free events in Stratford-upon-Avon

B. a series of activities in the London Shakespeare Centre

C. a series of exhibitions in the Folger Shakespeare Library

D. a live show of Shakespeare from Stratford-upon-Avon

【3】According to the next, a simply game to make a difficult conversation easy is called ________.

A. an ice-breaker

B. a suspicious man

C. a critic

D. a laughable man

【题目】A、B、C、D、E五种元素的原子序数依次递增，且均属于短周期元素，已知A是非金属元素，其电子层数与最外层电子数相等。Bn＋和C（n＋1）＋与氖原子具有相同的电子层结构，且C是两性元素。Dn－、E（n－1）－与氩原子具有相同的电子层结构。

（1）写出这五种元素的元素符号

A．__________；B.__________；C.__________；D.__________；E.__________。

（2）写出E单质与NaOH溶液反应的化学方程式：____________________。

（3）比较A、B、C、D、E的半径大小_____________________。

【题目】单词拼写

结合语境，根据汉语提示用单词的适当形式填空。

1. The salesman ________(说服) us to buy his product.

2. She is a ________(毕业生) student in literature.

3. They________(终于) realized that the whole thing was a joke.

4. They have planned a tight________(日程表) of travel.

5. He has the ability to________(组织).

6. The workers are ________(决定) to finish the job on time.

7. It is one day’s________(旅程) to get to the seaside.

8. There were perhaps ten________(步) between me and the bear.

【题目】 完形填空（每小题1分，满分20分）

阅读下面短文，从每题所给的A、B、C和D四个选项中，选出最佳选项。

Last week I was in the boarding area of the airport excited about my Easter trip home to see my parents. I was busy planning for the weekend, 1 I was taken out of my daydreaming by an elderly woman talking __2__ into her cellphone. She kept telling the person to 3 her where she was. She 4 the gate number again and again. She got a little louder each time she did that. Many people snickered (窃笑) because she was nearly __5__ and thought how silly old people could be.

Then I heard her say, ＂I’m 6 , but I can’t hear you. There seems to be something wrong with my hearing aid.＂ ＂That’s too 7 .＂ I thought as I moved forward to board the flight. Then I noticed her __8__ was becoming increasingly frantic (发狂似的) as she tried to understand the person on the other end of the phone. It was almost my 9 to board. I couldn’t 10 looking back at the woman. It made me think how __11__ I was to have my hearing. And I realized I could offer her some 12 .

I suddenly got out of the 13 and went to the woman. I showed her to 14 me the phone and shouted, ＂Let me help you. I’ll tell you what the person is 15 .＂ She looked at me and agreed 16 . I took the phone from her,17 who I was, listened for a moment, and told the woman her husband was __18__ her outside the airport as he could not enter the gate area. Finally, I pointed her in the right 19 .

It took me less than two minutes to finish the task, but my 20 in having been able to help her remains strong.

【1】A. but B. if C. so D. unless

【2】A. secretly B. loudly C. sadly D. quickly

【3】A. call B. help C. tell D. meet

【4】A. asked B. wrote C. repeated D. guessed

【5】A. shouting B. singing C. leaving D. dying

【6】A. sick B. tired C. sorry D. busy

【7】A. bad B. funny C. possible D. strange

【8】A. step B. tone C. friend D. mind

【9】A. duty B. idea C. task D. turn

【10】A. avoid B. stop C. continue D. keep

【11】A. normal B. lucky C. proud D. healthy

【12】A. money B. comfort C. help D. guide

【13】A. line B. space C. circle D. thought

【14】A. throw B. examine C. hand D. fix

【15】A. doing B. saying C. watching D. planning

【16】 A. honestly B. bravely C. angrily D. thankfully

【17】A. explained B. considered C. forgot D. lied

【18】A. thinking of B. turning to C. waiting for D. staring at

【19】A. queue B. direction C. street D. room

【20】A. pity B. hope C. love D. pride

【题目】(共10小题；每小题1.5分，满分15分)

阅读下面短文，在空白处填入 1个适当的单词或括号内单词的正确形式。

The World Health Organization (WHO) has made an appeal to scientists, drug manufacturers and governments. The WHO wants them to work together 1 (develop) drugs to fight 12 bacteria. These bacteria 2 (be) able to resist 3 (power) antibiotic（抗生素）drugs. The resistance is so unusually strong that all 12 have been given a special name: "superbug. "

The United Nations agency reported this week that 4 12 superbugs are a threat to human health. It said they have the ability to turn easily treatable infections into killers. The WHO says superbugs can also pass along genetic material 5 helps other bacteria become resistant to drug treatment.

Marie-Paule Kieny is the U. N. agency's assistant director-general. She said, "Antibiotic resistance is growing and we are fast running out 6 treatment options. "She urged governments to give drug companies reasons to develop new treatments. "If we leave it to market forces alone, the new antibiotics we most 7 (urgent) need are not going to be developed in time, "she said.

Antibiotic drugs can lose their effectiveness when people take more 8 less of than the amount 9 (require) by doctors. When this happens, infections that 10 (treat) easily in the past become resistant.

违法和不良信息举报电话：027-86699610 举报邮箱：58377363@163.com

精英家教网