题目内容

以下有关动物激素和植物激素的叙述中,错误的是(          )
A.都是由专门器官分泌的B.对新陈代谢、生长发育都有重要调节作用
C.在生物体内的含量都极少D.都是由活细胞产生的
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Jean is a young girl who comes from a rich and famous family. She goes to a good university and has almost everything that money can buy. The problem is that Jean’s family are so busy that they can hardly find time to be with her. Jean is quite lonely (孤独的). So she spends a lot of time on her QQ. She likes being anonymous (匿名的), talking to people who do not know about her famous family and her rich life. She uses the name Linda on QQ and has made a lot of friends.
Last year Jean made a very special friend on QQ. His name was David and he lived in San Francisco. David was full of stories and jokes. He and Jean had the same interest in rock music and modern dance. So it always took them hours to talk happily on QQ and sometimes they even forgot their time. Of course, they wanted to know more about each other. David sent a picture of himself. He was a tall, good-looking young man with big, happy smile. As time went by, they became good friends and often sent cards and small things to each other.
When Jean’s father told her that he was going on a business trip to San Francisco, she asked him to let her go with him. She wanted to give David a surprise for his birthday. She would take him the latest DVD of a rock singer. But when she knocked on David’s door in San Francisco, she found that her special friend was a 70–year-old man named Jim! How disappointed Jean was!
【小题1】Jean spends a lot of her time on QQ because she is_______.
A.richB.young C.a bad studentD.lonely
【小题2】Jean thought “David” was special because he ________.
A.made her very happy on QQB.was from San Francisco
C.was tall and good-lookingD.was rich
【小题3】What are both Jean and “David” interested in? 
A.Pop music and sports. B.Music and science.
C.Rock music and modern dance. D.Stories and jokes.
【小题4】Which of the following is True?
A.Jean has got everything in her life.B.“David” and Jean sent cards to each other.
C.“David” didn't tell Jean his real address.D.Jean's family members often get together.
【小题5】What’s the main idea of the passage? 
A.Don’t go to meet those you get to know on QQ.
B.People don’t use their real names on QQ so often.
C.Don’t believe those you get to know on QQ easily.
D.Don’t spend much time on QQ.
小刚家准备建一栋新房,爸爸买了一堆材料相同的石子,小刚选取一块石子在实验室测它的密度.
他先将托盘天平放在水平桌面上,调节托盘天平平衡时,发现指针停在分度盘的右侧,要使天平平衡,应将横梁右端的平衡螺母向   (左/右)移动;当他用天平测物体质量时,发现指针偏向分度盘的左侧,这时应该在天平右盘中      (增加/减少)砝码;
测小石子的密度,主要实验步骤是: A.用量筒测出小矿石的体积;B.将小矿石从水中取出,立即放在已调节平衡的天平盘上,加减砝码和调节游码,测出小矿石的质量;C.再用密度计算公式求出小石子的密度.请你评估:这一实验过程测算出的密度结果______(选填“偏大”、 “偏小”或“准确”),原因是_______________________.

刚按图甲所示的方法测石子的质量,请指出操作中的三个错误:
                                                      
                                                      
                                                      
纠正错误后继续实验,当盘中所加砝码和游码位置如图19乙所示时天平平衡,则此石子的质量为      g.在量筒内装有一定量的水,该石子放入前、后的情况如图19丙所示,则石子的体积是       cm3,此石子的密度是           kg/m3

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