题干

如图所示,a、b、c为对胚芽鞘做不同处理的实验,d为一植株被纸盒罩住,纸盒的一侧开口,有单侧光照.下列对实验结果的描述,正确的是( )

A:a直立生长,b、c向光弯曲生长

B:a、b向光弯曲生长,c背光弯曲生长

C:图d中如果固定植株,旋转纸盒,一段时间后,植株向左弯曲生长

D:图d中如果将纸盒和植株等速一起旋转,则植株向纸盒开口方向弯曲生长

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D

同类题4

完形填空
    Denny Crook was a famous photographer(摄影师). He traveled all over the world, taking pictures for magazines and newspapers, and won many prizes.
    “I'll do anything to get a good photo,” he often said. “I'll go anywhere at any time, even if it is 1.”
    And he told the2. He had photos of earthquakes, forest fires, floods and even wars. If something interesting happened, Denny went to photo it.
    He was a married(已婚的) man and his wife often asked him to take her with him, but he always 3.”I'll travel for my work, not for 4,” he told her . “You won't enjoy yourself, and I won't have 5 to look after you. Sometimes there’s not even anywhere to6, and I have to sleep outside. I often don't have a good 7or a bath for days. You won't like it.”
    “Denny, I'm not a child,” his wife didn't 8. “I can look after myself. Please take me with you the next time you go overseas.”
Denny did not say anything, but he9about it, and when he was asked to go to Africa he said to his wife, “You can come to Africa with me if you want to. I've got to take photos of wild 10there. It should be interesting and not too uncomfortable.”His wife was very11, and at first she had a very enjoyable time.
    Then Denny went to 12 some lions to photo. His wife went with him, but before long they became separated(分开). She walked down one path while he walked down the other.
    Suddenly, Denny heard her 13. He ran back and saw her running towards him. A huge lion was running after her. Quickly Denny took his camera out of its case and14 it at his wife and the lion. Then he shouted, “15, woman! I can't get you both in the picture!”