0  299309  299317  299323  299327  299333  299335  299339  299345  299347  299353  299359  299363  299365  299369  299375  299377  299383  299387  299389  299393  299395  299399  299401  299403  299404  299405  299407  299408  299409  299411  299413  299417  299419  299423  299425  299429  299435  299437  299443  299447  299449  299453  299459  299465  299467  299473  299477  299479  299485  299489  299495  299503  447090 

7. 要得到函数的图象,可以把函数的图象( )

A.向左平移个单位     B.向右平移个单位 

C.向左平移个单位     D.向右平移个单位

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6.二次函数满足,又,若在[0,]上有最大值3,最小值1,则的取值范围是(   )

A.      B.      C.     D. [2,4]

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5.设函数f(x)是R上以5为周期的可导偶函数,则曲线y=f (x)在x=5处的切线的斜率为(   )

A.-       B.0         C.        D.5

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4.函数f(x)=的零点所在的大致区间是(   )[

     A.(1, 2)              B.(2,e)             C.(e,3)               D.(e,+∞)

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3.已知p:则p是q的(   )

    A.充分不必要条件    B.必要不充分条件    C.充要条件   D.既不充分也不必要条件

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2. 若cos(2π-α)=∈(-),则sin(π-α)=(   )  B

     A.-              B.-                C.                  D.±

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1.已知集合,则集合=(   )

A.{}       B.{}  C.{}   D.{}

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(2009年安徽一模)Like dogs,birds breathe in air and get oxygen to supply body tissues,while fish breathing depends on getting oxygen from water through parts of its body.

However,bird respiration(呼吸)is different from dogs and is much more efficient than that of other animals. The lungs take up just 2 percent of a bird’s body volume,yet the bird quickly takes in large amounts of oxygen and quickly removes waste and excess heat.

There are actually two respiration systems,internal and external.

The external respiration system uses the lungs and a series of air sacs(袋囊)distributed throughout the body so that the oxygen supply is in direct communication with body parts. Oxygen is taken in and exchanged for carbon dioxide waste in the blood;then the carbon dioxide is moved out. So far,much like dogs.

However,in an important difference,the air flow in a bird is one way,through a series of tubes and cells,rather than two ways,in and out of the lungs,as it is in dogs. A constant stream of air goes through lungs and then is channeled through the complex system of air sacs,which also help remove excess heat,as well as through hollow bones. The gases are then channeled forward through the lungs again,then through more air sacs,finally ending up in the windpipe,and are expelled from the body.

The air sac system is bigger than the lungs and takes up 15 percent of the chest and belly area.

Meanwhile,the bird’s great oxygen needs are also handled by the internal breathing system. The oxygen,stored primarily in body fat tissue,is burned through the process of cell respiration. This process produces both muscular energy and heat.

How does a bird breathe?
Ways to get oxygen
For birds and dogs,by breathing in air For fish,from 1.________through its body
Two 2.______systems
Internal and external
External respiration system
Using the lungs and a series of air sacs To communicate with body parts 3.________
4.____sac system
Bigger than the lungs
Taking up a 5.______part of the chest and belly area
6.______of bird breathing
A stream of air
▲going through lungs without 7.______
▲being channeled through the complex system of air sacs and through 8.________bones
▲being  9.______forward through the lungs again,then through more air sacs
▲ 10.______in the windpipe and are expelled from the body

答案:1.water 2.respiration 3.directly/straight 4.Air 5.small 6.Process 7.stopping/neled pleting/finishing/ stopping

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