问题 选择题

鱿鱼称“鱼”而非鱼,而有些动物不称“鱼”而属鱼,如下列动物中的 (  )   

A.海豚

B.海狮

C.海豹

D.海马

答案

答案:D

题目分析:鱼类的特征有生活在水中,鱼体表大都覆盖有鳞片,减少水的阻力,用鳃呼吸,用鳍游泳,海马因其头部酷似马头而得名,生活在水中,有鳍,用鳃呼吸,在水中成直立状前进,是一种奇特而珍贵的近陆浅海小型鱼类,海豚、海狮和海豹尽管都生活在水中,但具有胎生、哺乳的特征属于哺乳动物。

阅读理解

第三部分阅读理解(共两节,满分40分)

第一节(共15小题;每小题2分,满分30分)

  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,并在答题卡上将该项涂黑。

A

  Soon it may be harder to stop and smell the roses.

  Growing levels of air pollution from power plants and automobiles have reduced flower fragrances (芬芳) by up to 90 percent in the US.That is compared with pre-industrial levels,a new study has found.

  The trend is unpleasant for human noses,but may be life - threatening for bees and butterflies.

  "Many insects find flowers by folowing the scent(香味) produced by those flowers," said the studies lead author Jose D.Fuentes,an environmental scientist at the University of Virginia.

  "The increasing pollution makes it difficult for them to locate the flowers and feed on their nectar(花蜜)."

  Scientists have alrady known that flowers produce scent molecules(分子) that bond with pollutants.The process breaks down the plants' sweet smell.

  With more pollution in the air,the scent molecules don't remain effective as long and travel shorter distances on the wind.

  The new study suggests that in the mid - 19th century,when pollution levels were first recorded,scent molecules would have been able to travel some 1,000 to 1,200 meters.

  Today,in the polluted air found downwind of large cities,scentst may only make it some 200 to 300 meters.

  The report was recently published in the journal,Atmospheric Environment.

  Bee farmers have reported that bee populations are dropping dramatically in many parts of the world in recent years. Could these missing scents be a factor?

  Scientists trying to hind the cause of bee population declines have blamed bacteria,pesticides,and even cellphone radiation.

  Jay Evans,an entomologist(昆虫学者) at the US Department of Agriculture's bee research laboratory,was interested in the new study.But he says he hasn't seen bee behavior that suggests trouble with scents.

  "Over the last couple of summers I don't think the bees in this area were bringing in much less food,"he said.

  "It might be that they had to work harder,but it seems like as long as there were bees to collect food they were finding flowers somewhere."

  But Fuentes fears that the fading smell of flowers may stress insects that are already faced with other threats.

  "The effects shown in these studies will simply exacerbate whatever the bees are going through right now,"he said.

  "It's something that is really worthwhile paying attention to."

  56.What's the passage mainly about?

   A.How greatly air plooution affects our lives.

   B.Effects of air pollution on bee populations.

   C.Measures to fight air pollution.

   D.The rapid decline of bee populations in the world.

  57.According to the passage,Jay Evans probably agrees that ______ .

   A.bees are the insect that suffers most from air pollution

   B.bees are at risk of dying out owing to air pollution

   C.the fading smell of flowers doesn't affect bees so greatly as was thought

   D.as is often the case,bees fail to locate the flowers because of the missing scents

  58.The word"exacerbate" in the last paragraph but one probably means ______.

   A.worsen B.improve C.get rid of D.decrease

  59.Which of the following is NOT true according to the passage?

   A.The more air pollution there is in a region,the greater the destruction of the flower scents.

   B.Bacteria,pesticides,and cellphone radiation are blamed for causing the decline of bees.

   C.The scent molecules produced by flowers in a less polluted environment oculd travel longer and farther.

   D.Air pollution does more harm to insects such as bees and butterflies than human beings.

单项选择题