为探究种子萌发的环境条件，小华设计了如下实验：在甲、乙、丙三个培养皿中分别放入等

发布时间：2017-06-04 18:55 │ 来源：www.tikuol.com

题型：选择题

问题：

为探究种子萌发的环境条件，小华设计了如下实验：在甲、乙、丙三个培养皿中分别放入等量的面巾纸，在面巾纸的上面都放25粒绿豆种子，然后将它们放在不同条件下进行培养，数日后记录种子萌发的情况如下表．

装置	甲	乙	丙
温度	23℃	23℃	0℃
面巾纸干湿状态	潮湿（含一定量的水分）	干燥	潮湿（含一定量的水分）
种子萌发的数量	23	0	0

根据小华的实验设计，她探究的实验变量时什么？（　　）

A．温度和光照

B．温度和水分

C．光照和水分

D．水分和氧气

考点：探究实验：种子萌发的环境条件

题型：选择题

选出不是同类的一个单词，将其序号填入题前括号内。

( )1. A. pen
( )2. A. book
( )3. A. food
( )4. A. cat
( )5. A. seat

B. pencil
B. face
B. red
B. dog
B. cake

C. pencil-case
C. nose
C. yellow
C. hat
C. bread

D. sister
D. eye
D. green
D. panda
D. hamburger

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题型：选择题

完形填空。

                                          How 3D Movies Work   .
     Do you know 3D movies? When you see one, it's like the story  l in front of you, and you are a part ofit. 3D movies are exciting to   2   , but do you
know how3      them, and     4   you need to wear a pair of 3D glasses? To
understand these questions, let's make an easy   5  .
     O Put a finger   6   your eyes.
     O Cover your lef't eye and look at the finger.
     O Cover your right eye and look at the finger.
     What do you see:l The finger you see with your left eye is in a different
position from the one you see with your right eye. This means you get two
images(图像) when you look at   7     _ with both your eyes. To makea 3D
movie, people have to get two images at the same time,   8_ they use two
video cameras.  When playing a 3D movie, they use two projectors (放机)
at the same time.  This brings two images together on the screen. Then, we
use 3D glasses to separate(识别) the two images. One image enters one eye
and   9 enters the other eye.
     Then our brains   10     the two images together. In this way, we get 3D
pictures.

( )1. A. happen
( )2. A. watch
( )3. A. make
( )4. A. when
( )5. A. examl)le
( )6. A. in front of
( )7. A. everything
( )8. A. because
( )9. A. other
( )10.A. let

B. happened
B. see
B. to make
B. why
B, picture
B. in the front of
B. anything
B. so
B. the other
B. put

C. to happen
C. look
C. making
C. which
C. experiment
C. behind
C. something
C. and
C. others
C. take

D. happening
D. notice
D. made
D. what .
D. mowe
D. beside
D. nothing
D. but
D. the others
D. bring

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题型：选择题

首选放疗或化疗的纵隔肿瘤是（）

A.淋巴瘤

B.胸腺瘤

C.畸胎类肿瘤

D.胸骨后甲状腺肿

E.神经源性肿瘤

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题型：选择题

殷夫的“红色鼓动诗”有何特点？

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题型：选择题

v2500发动机反推系统的方向活门是怎样控制的（）

A.油门杆

B.油门杆通过EEC和EIU

C.油门杆通过EEC

D.EEC通过EIU

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