平安夜学生们送给海伦的礼物是一个漂亮的洋娃娃和（）。

A、可爱的金丝雀

B、毛茸茸的白熊

相关问题推荐

• 下图表示植物不同器官对生长素的反应。请据图回答：

  

  （1)A点所对应的生长素浓度对茎生长的效应是___\_，对芽生长的效应是_______。（2)某生物兴趣小组开展“萘乙酸（生长素类似物）促进某种植物插条生根的最适浓度是多少”的探究实验，按照下表设计浓度梯度（单位：mol/L)：

  

  为了进一步准确地测定最适浓度，应当采取什么改进措施？__\_在农业生产上用萘乙酸溶液浸泡植物插条生根时，除了考虑最适浓度外，还应考虑的因素有________（至少回答两点)。（3)有人发现在植物根的向地性弯曲部位除了生长素的分布不同外，在近地侧同时也集中了大部分的乙烯，由此可知：植物的生长发育过程是_______的结果。（4)在植物的生长发育过程中，达尔文在研究生长素时，将带有尖端的金丝雀虉草的胚芽鞘（A)和除去尖端的金丝雀虉草的胚芽鞘（B)置于单侧光下，结果A弯向光源生长，B不生长也不弯曲，该实验的推论是__\_。植物的向光性对植物叶片生长的意义是________。

  查看答案
• 在进化过程中，鸟嘴形成了各种不同的形状，下图的是鹦鹉、鹭、老鹰和金丝雀头部的花香，从嘴型上看，金丝雀应当是（　）。

  A.

  B.

  C.

  D.

  查看答案

• 《长恨歌》讲述的是—个女人四十年的情与爱，作者细腻而绚烂的笔写得哀婉动人，__________。王琦瑶从“上海小姐”到“金丝雀”，最后回归普通百姓，她内心的情感潮水劫从未入画横线部分最恰当的一项是（）。
  A．跌宕起伏平复B．汹涌澎湃平息C．汹涌澎湃平复D．跌宕起伏平息

  查看答案
• 共用题干第二篇
  Where Have All the Frogs Gone?
  In the 1980s,scientists around the world began to notice something strange:Frogs
  were disappearing. More recent research has shown that many kinds of amphibians（两栖
  动物）are declining or have become extinct. They have been around for a long time一over
  350 million years.Why are they dying out now?
  Scientists are seriously concerned about this question.First of all,amphibians are an
  important source of scientific and medical knowledge.By studying amphibians,scientists
  have learned about new substances that could be very useful for treating human diseases.
  Further research could lead to many more discoveries,but that will be impossible if the
  amphibians disappear.
  The most serious aspect of amphibian loss,however,goes beyond the amphibians
  themselves.Scientists are beginning to think about what amphibian decline means for the
  planet as a whole.If the earth is becoming unlivable for amphibians,is it also becoming
  unlivable for other kinds of animals and human beings as well?
  Scientists now believe that amphibian decline is due to several environmental factors.
  One of these factors is the destruction of habitat,the natural area where an animal lives.
  Amphibians are very sensitive to changes in their habitat.If they cannot find the right
  conditions,they will not lay their eggs一These days,as wild areas are covered with
  houses,roads,farms,or factories,many kinds of amphibians are no longer laying eggs.
  For example,the arroyo toad（蟾蜍）of southern California will only lay its eggs on the
  sandy bottom of a slow-moving stream.There are very few streams left in southern
  California,and those streams are often muddy because of building projects. Not
  surprisingily,the arrovo toad is now in danaer of extinction.
  There are a number of other factors in amphibian decline.Pollution is one of them.In
  many industrial areas,air pollution has poisoned the rain,which then falls on ponds and
  kills the frogs and toads that live there,In farming areas,the heavy use of chemicals on
  crops has also killed off arrtphibians.Another factor is that air pollution has led to increased
  levels of ultraviolet (UV) light. This endangers amphibians, which seem to be especially
  sensitive to UV light. And finally, scientists have discovered a new disease that seems to
  be killing many species of arnpttibians in different parts of the world.
  All these reasons for the disappearance of amphibians are also good reasons for more
  general concern. The destrriction of land, the pollcition of the air and the water, the
  changes in our atmosphere, the spread of diseases-these factors affect human beings,
  too. Amphibians are especially sensitive to environmental change. Perhaps they are like
  the canary （金丝雀）bird that coal miners once used to take down into the mines to detect
  poisonous gases. When the canary became ill or died,the miners knew that dangerous
  gases were near and their own lives were in danger. Coal miners once used the canary bird to detectA:poisonous gases. B:air pollution.C:water leakage. D:radiation.

  查看答案

• 从莫斯科奥运会起，一支鸟类合唱团在福缅科指挥下，3年时间演出2000多场世界名曲和流行歌曲。这种鸟是：（）

  A、黄雀

  B、金翅雀

  C、椋鸟

  D、金丝雀

  查看答案