ChaseDream
搜索
返回列表 发新帖
00:00:00

When a caterpillar emerges from the egg on a tree branch, it immediately climbs upward until it finds a leaf bud to eat. Biologists thought that this behavior displayed an innate tendency to move in the direction opposite to the pull of gravity. In a recent experiment, a strong light source was placed at the bottom of a tree, and caterpillars, after hatching, climbed downward.

Which of the following hypotheses is best supported by the statements given?

正确答案: C

更多相关帖子

524

帖子

15

好友

4712

积分

ChaseDream

注册时间
2003-03-17
精华
8
解析
查看: 1698|回复: 1
打印 上一主题 下一主题

[求助]prep1-33

[复制链接]
楼主
发表于 2009-10-10 10:29:00 | 只看该作者

[求助]prep1-33

(31934-!-item-!-188;#058&005658)

 

When a caterpillar emerges from the egg on a tree branch, it immediately climbs upward until it finds a leaf bud to eat.  Biologists thought that this behavior displayed an innate tendency to move in the direction opposite to the pull of gravity.  In a recent experiment, a strong light source was placed at the bottom of a tree, and caterpillars, after hatching, climbed downward.

 

Which of the following hypotheses is best supported by the statements given?

 

(A) Caterpillars have an innate tendency to move in the direction of gravity.

(B) Newly hatched caterpillars are unable to see in the dark.

(C) Newly hatched caterpillars move towards the strongest light source in the environment.

(D) Newly hatched caterpillars move toward the leaf bud nearest to them.

(E) The eyes of newly hatched caterpillars become less sensitive to light over time.

 

答案是C   我选择A,为什么不对呢?? 

大家帮忙解释一下吧!!

沙发
发表于 2009-10-10 11:33:00 | 只看该作者

开始它是往上,往引力相反的方向

后来下面有光了,它就往有光的地方走了,也就是引力相反的方向

C比较正确吧

小生愚见

您需要登录后才可以回帖 登录 | 立即注册

Mark一下! 看一下! 顶楼主! 感谢分享! 快速回复:

手机版|ChaseDream|GMT+8, 2024-11-14 12:30
京公网安备11010202008513号 京ICP证101109号 京ICP备12012021号

ChaseDream 论坛

© 2003-2023 ChaseDream.com. All Rights Reserved.

返回顶部