7.Scientists have discovered a special biological behavior in dolphins(海豚) that could lead to a treatment for late-onset diabetes(晚發(fā)的糖尿病) in humans.Studies on dolphins found that healthy dolphins switch into a diabetic-like state overnight when they are not feeding,but return to normal when they eat the following morning.
The extraordinary finding has led scientists to suggest that dolphins have"genetic switch"that allows them to imitate diabetes while they arenot feeding for a night,without suffering any ill effect.
If researchers can identify a similar genetic pathway in human,they may be able to develop drugs to effectively switch off diabetes.Some 2.2million people in Britain have type 2(or late-onset) diabetes,a figure that is expected to reach 4million by 2025as a consequence of rising levels of obesity(肥胖).
The tissuesof people with type 2diabetes have become resistant to insulin(胰島素)so they lose the ability to control sugar levels in their blood.The condition can damage the heart,eyes,kidneys(腎臟) and nerves and contribute to 5% of all deaths,according to the World Healthy Organisation.
Dolphins appear to imitate diabetes to keep high levels of blood sugar when food is rare.Like humans,dolphins need some sugar in their blood for their brains to function normally.Venn-Watson's team analysed 1,000blood samples(樣本) from 52dolphins while theydidn't eat anything overnight and fed in the morning.At night time,the dolphins'metabolism(新陳代謝)changed greatly and showed similar characteristics to that seen in people with type 2diabetes.
"It is our hope that this discovery can lead to new ways to prevent,treat and maybe even cure diabetes in humans,"said Stephanie Venn-Watson,director of clinical research at the National Marine Foundation in San Diego.
72.What's the main idea of the passage?A
A.Humans get some ideaoftreatingdiabetes from dolphins.
B.Dolphins can switch into a diabetic-like state overnight.
C.Humans can suffer the same disease as dolphins.
D.Dolphins should be fed regularly to avoid diabetes.
73.The key to applying the finding to curing human diabetes lies inC.
A.producing insulin in a larger amount
B.developing drugs from healthy dolphins
C.identifying a similar genetic pathway in human
D.a(chǎn)nalysingmore blood samples from hungrydolphins
74.Which of the following statements is TRUE according to the passage?B
A.Scientists have found a similar genetic switch in humans.
B.More British people will suffer type 2diabetes due to obesity.
C.2.2million people with type 2diabetes die in Britain every year.
D.Dolphins imitate diabetes to avoid a high blood sugar level.
75.What will happen to dolphins if not fed for a night according to Venn-Watson?D
A.Their metabolism breaks down.
B.They become resistant to insulin.
C.Their heart and kidneys are damaged.
D.They keep high levels of blood sugar.
分析 本文是一篇說明文.文章主要介紹最近科學家們發(fā)現(xiàn),當海豚在夜間不進食時,血糖含量會升高,類似于人類的糖尿病患者.但是海豚在夜間恢復(fù)進食后,血糖又回歸正常.科學家希望從中找到治愈糖尿病的方法.
解答 72.A主旨大意題.根據(jù)第一段"Scientists have discovered a special biological behavior in dolphins that could lead to a treatment for late-onset diabetes in humans"可知,文章介紹的是人類可以從海豚的行為上得到一些治療糖尿病的主意.故選A.
73.C細節(jié)理解題.根據(jù)第三段"If researchers can identify a similar genetic pathway in human,they may be able to develop drugs to effectively switch off diabetes"可知將這個發(fā)現(xiàn)應(yīng)用于治療糖尿病人的關(guān)鍵是在人類身上識別相似的基因通道.故選C.
74.B細節(jié)理解題.根據(jù)第三段"Some 2.2million people in Britain have type 2(or late-onset) diabetes,a figure that is expected to reach 4million by 2025as a consequence of rising levels of obesity"可知更多的英國人因為肥胖患II型糖尿。蔬xB.
75.D細節(jié)理解題.根據(jù)倒數(shù)第二段"Dolphins appear to imitate diabetes to keep high levels of blood sugar when food is rare"可知如果海豚一個晚上不吃東西的話血糖會保持在一個高水平.故選D.
點評 本文是一個科教類閱讀理解.題目涉及多道細節(jié)理解題,做題時結(jié)合原文和題目有針對性的找出相關(guān)語句進行仔細分析,結(jié)合選項選出正確答案.推理判斷題也是要在抓住關(guān)鍵句子的基礎(chǔ)上合理的分析才能得出正確答案,切忌胡亂猜測,一定要做到有理有據(jù),在做主旨大意題時考生首先要仔細閱讀短文,完整了解信息,準確把握作者觀點,確定主旨..