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科目:高中英語 來源:2012屆江西省新干二中高三下學(xué)期第一次夜?荚囉⒄Z試卷(帶解析) 題型:閱讀理解
Can people change their skin color without suffering like pop king Michael Jackson? Perhaps yes.Scientists have found the gene that determines skin color.
The gene comes in two versions, one of which is found in 99 per cent of Europeans.The other is found in 93 t0 100 per cent of Africans, researchers at Pennsylvania State University report in the latest issue of Science.
Scientists have changed the color of a dark - striped zebrafish(斑馬魚) to uniform gold by inserting a version of the pigment(色素) gene into a young fish.As with humans, zebrafish skin color is deter-mined by pigment cells,which contain melanin(黑色素).The number, size and darkness of melanin perpigment cell determine skin color.
It appears that, like the golden zebrafish, light - skinned Europeans also have a mutation (變異) in the gene for melanin production.This results in less pigrnented skin.
However, Keith Cheng, leader of the research team, points out that the mutation is different in hu-man ancl zebrafish genes.
Humans acquired dark skin in Africa about l.5 million years ago to protect bodies from ultra - violetrays of the sun. which can cause skin cancer.
But when modem humans leave Africa to live in northem latitudes, they need more sunlight on their skin to produce vitamin D. So the related gene changes, according to Cheng.
Asians have the same version of the gene as Africans, so they probably acquired their light skin through the action of some other gene that affects skin color, said Cheng.
The new discovery could lead to medical treatments for skin cancer.lt also could lead to research in-to ways to change skin color without damaging it like chemical treatment did on Michael Jackson.
【小題1】Scientists have done an experiment on a dark -striped zebrafish in order to
A.fincl the different genes o humans' |
B.prove the humans' skin color is determined by the pigment gene |
C.find out the reason why the Africans' skin color is dark |
D.fincl out the ways of changing people's skin color |
A.nowadays people who want to change their skin color have to suffer 8 lot from the damage caused by the chemical treatment |
B.Europeans and Africans have the same gene |
C.the new discovery could help to find medical treatments for skin cancer |
D.there are two kinds of genes |
A.scientists have found out that people's skin color is determined by the gene |
B.the new discovery could lead to research into ways to change skin color safely |
C.pop king Michael Jackson often changed his skin color as he liked |
D.people can not change their skin color without any pain |
A.they are bom light - skinned people |
B.light - skinned Europeans have mutation in the gene for melanin production |
C.they have fewer activities outside |
D.they pay much attention to protecting their skin |
A.neutral | B.negative | C.indifferent | D.positive |
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科目:高中英語 來源:2012-2013學(xué)年吉林省龍井市三中高二下學(xué)期第一次月考英語試卷(帶解析) 題型:填空題
根據(jù)首字母或中文提示寫出單詞的正確形式(每空0.5分)共5分。
【小題1】What we choose and decide forms our life, but a________ decides our choice and decision.
【小題2】As is known to all, Mo Yan was awarded the 2012 Nobel Prize for l________.
【小題3】Recently I watched a cartoon a___________ from the famous drama by Shakespeare.
【小題4】It is known to all that fresh air is b___________ to our health.
【小題5】The visiting president on Thursday expressed his deep s___________ on the deaths and damages caused by the earthquake in Guatemala.
【小題6】His parents d__________ when he was 10 months old, and he was brought up by his grandfather.
【小題7】The lady is o___________ and she wants to lose weight.
【小題8】Nowadays China is developing fast, which is e_______ by other countries.
【小題9】The 2013 is a great year for us to rethink our future, r________ on our past mistakes and show our achievements.
【小題10】In order to repay my mother for her kindness, I’ll retell the stories for her in v________ detail.
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科目:高中英語 來源:福建省2009-2010學(xué)年高一下學(xué)期期中考試英語試題 題型:短文填詞
第II卷(共20分)
第一部分 短文填詞(10分)
閱讀下面短文,根據(jù)以下提示:1)漢語提示,2)首字母提示,3)語境提示。在每個(gè)空格內(nèi)填入一個(gè)適當(dāng)?shù)挠⒄Z單詞,并將該詞完整地寫在右邊相對(duì)應(yīng)的橫線上。所填單詞要求意義準(zhǔn)確,拼寫正確
Nowadays, some students would not like to live in a dorm.
Instead, they rent houses outside the school. There are (81) (優(yōu)點(diǎn))
for both. (82)L in a dorm can increase friendships and cooperation between classmates. And of (83) it is safer. A dorm is more like a society, (84) teaches students to learn to adapt to each other, thus preparing for school life later. As for renting houses to live (85)a , it’s better for study (86) you can feel free in your own room without being disturbed by (87) (其他人). As a result, you can have more time and devote yourself to (88) (學(xué)習(xí))whole-heartedly. But there may appear some safety (89) (問題) as you live outside of the school. Anyhow, as a student, I (90) living in a dorm to renting a house.
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科目:高中英語 來源:2013屆浙江省高二上學(xué)期期中考試英語試卷 題型:單詞拼寫
單詞拼寫(每題1分,共10分)
1.It’s clear that the little money he earns can hardly
s______ a family as large as his.
2.The West Lake is one of the popular tourist a______ at home and abroad.
3.The goods you bought will be d______ to your house at noon tomorrow.
4.An accident is l______ to happen if you drive fast.
5.Make up a short dialogue, using the u______ phrases in the passage.
6.The Yellow River is one of the top ten rivers in l________ in the world.
7.Children are c________ to know everything they see.
8.Seeing the naughty boy making a noise, Father said to him, “B______ yourself!”
9. Nowadays every classroom in our school is e______ with an overhead projector(投影儀).
10.He gave v________ excuses for not attending the meeting, but none was convincing.
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科目:高中英語 來源:2010年高三名校精華重組英語試題(3) 題型:其他題
第二卷(兩部分,共35分)
第一節(jié) 請(qǐng)認(rèn)真閱讀下面對(duì)話,并根據(jù)各題所給首字母的提示,在方框的右欄標(biāo)有題號(hào)的橫線上,寫出一個(gè)英語單詞的完整、正確的形式,使對(duì)話通順。
Jack(J):Where have you been, Laura?
Laura(L): Oh, I’ve just been to a s 76 made76_________________
by a famous p 77 from Beijing University77_________________
J: What is it about?
L: He mentioned something c 78 the concept of “harmonious society” in his speech.
78_________________
J: Oh, that’s something people keep t 79 about
nowadays! Then what did he say about it?79_________________
L: He said that we should not only get a 80 well with
other people, but also live in harmony with n 81 .80_________________
81_________________
J: I’m in complete a 82 with him. While developing 82_________________
the economy, we are i 83 with the ecology. 83_________________
L: Yes. It’s high time we considered doing something
to improve the environment p 84 by human beings. 84________________
J: Hopefully, our government is taking m 85 to
deal with the consequences.85________________
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