ChaseDream
搜索
返回列表 发新帖
00:00:00

In order to withstand tidal currents, juvenile horseshoe crabs frequently burrow in the sand. Such burrowing discourages barnacles from clinging to their shells. When fully grown, however, the crabs can readily withstand tidal currents without burrowing, and thus they acquire substantial populations of barnacles. Surprisingly, in areas where tidal currents are very weak, juvenile horseshoe crabs are found not to have significant barnacle populations, even though they seldom burrow.

Which of the following, if true, most helps to explain the surprising finding?

正确答案: E

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: 5804|回复: 4
打印 上一主题 下一主题

译成中文也没懂!

[复制链接]
跳转到指定楼层
楼主
发表于 2011-5-4 21:37:30 | 只看该作者 回帖奖励 |倒序浏览 |阅读模式
In order to withstand tidal currents, juvenile horseshoe crabs frequently burrow in the sand.Such burrowing discourages barnacles from clinging to their shells.When fully grown, however, the crabs can readily withstand tidal currents without burrowing, and thus they acquire substantial populations of barnacles.Surprisingly, in areas where tidal currents are very weak, juvenile horseshoe crabs are found not to have significant barnacle populations, even though they seldom burrow.



Which of the following, if true, most helps to explain the surprising finding?



  1. Tidal currents do not themselves dislodge barnacles from the shells of horseshoe crabs.

  2. Barnacles most readily attach themselves to horseshoe crabs in areas where tidal currents are weakest.

  3. The strength of the tidal currents in a given location varies widely over the course of a day.

  4. A very large barnacle population can significantly decrease the ability of a horseshoe crab to find food.

  5. Until they are fully grown, horseshoe crabs shed their shells and grow new ones several times a year.
    答案是E!没懂!

收藏收藏1 收藏收藏1
沙发
发表于 2011-5-4 22:06:14 | 只看该作者
现象(论据):为了避免被潮汐带到海里,小螃蟹要打洞,所以barnacle很难贴在壳上。小螃蟹长大了,不打洞了,壳上就可以粘很多barnacle。

但是作者观察到,潮汐很弱的地方壳上粘的barnacle也不多。

就说明挖不挖洞,只能是barnacle粘在壳上的必要非充分条件,还其他的原因影响壳上barnacle的量。

A. 削弱
B. 削弱
C. 无关
D. 这个选项有点迷惑,如果大量的barnacle会减弱crab的捕食能力,那么有大量barnacle的crab就很有可能挂掉,从而导致剩下的crab身上都没多少barnacle了。但是题目没这么说,don't go out of scope.
E. crab一年就要换好几次壳,长在上面的barnacle在换壳的时候被甩掉了~
板凳
 楼主| 发表于 2011-5-5 14:59:45 | 只看该作者
如果考试的时候出现这种完全不懂的,或者脑子不转了,咋办啊!
地板
发表于 2011-5-5 15:46:54 | 只看该作者
不会的不会的,要相信女银的直觉~
5#
发表于 2012-5-12 19:15:39 | 只看该作者
不会的不会的,要相信女银的直觉~
-- by 会员 kikisunflower (2011/5/5 15:46:54)


哈哈哈~~~觉得这个回帖好好笑
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, 2024-11-6 18:25
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