中间图

Or
阅读RC-10327 (第3/4题) Time Cost00:00
收藏
该题平均耗时:2m31s,平均正确率:54.9% 添加做题笔记

Recently biologists have been interested in a tide-associated periodic behavior displayed by the diatom Hantzschia virgata, a microscopic golden-brown alga that inhabits that portion of a shoreline washed by tides (the intertidal zone). Diatoms of this species, sometimes called “commuter” diatoms, remain burrowed in the sand during high tide, and emerge on the sand surface during the daytime low tide. Just before the sand is inundated by the rising tide, the diatoms burrow again. Some scientists hypothesize that commuter diatoms know that it is low tide because they sense an environmental change, such as an alteration in temperature or a change in pressure caused by tidal movement. However, when diatoms are observed under constant conditions in a laboratory, they still display periodic behavior, continuing to burrow on schedule for several weeks. This indicates that commuter diatoms, rather than relying on environmental cues to keep time, possess an internal pacemaker or biological clock that enables them to anticipate periodic changes in the environment. A commuter diatom has an unusually accurate biological clock, a consequence of the unrelenting environmental pressures to which it is subjected; any diatoms that do not burrow before the tide arrives are washed away.

This is not to suggest that the period of this biological clock is immutably fixed. Biologists have concluded that even though a diatom does not rely on the environment to keep time, environmental factors—including changes in the tide’s hydrostatic pressure, salinity, mechanical agitation, and temperature—can alter the period of its biological clock according to changes in the tidal cycle. In short, the relation between an organism’s biological clock and its environment is similar to that between a wristwatch and its owner: the owner cannot make the watch run faster or slower, but can reset the hands. However, this relation is complicated in intertidal dwellers such as commuter diatoms by the fact that these organisms are exposed to the solar-day cycle as well as to the tidal cycle, and sometimes display both solar-day and tidal periods in a single behavior. Commuter diatoms, for example, emerge only during those low tides that occur during the day.

According to the passage, the periodic behavior displayed by commuter diatoms under constant laboratory conditions is characterized by which of the following?



  • 分析A选项
    xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
  • 分析B选项
    xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
  • 分析C选项
    xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
  • 分析D选项
    xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
  • 分析E选项
    xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
该题目由网友EQApZAF提供。更多GMAT题目请

网友解析

当前版本由 aaaaa 更新于2015-11-11 14:18:57感谢由 aaaaa 对此题目的解答所做出的贡献。
定位到when diatoms are observed under constant conditions in a laboratory, they still display periodic behavior, continuing to burrow on schedule for several weeks.说的是在consistent实验室环境下,还是会周期性挖洞。

a 更不可预测,无中生有
b 符合定位句
c 在自然环境下如何,不符
d 在实验环境有变化,容易排除
e 更敏感,容易排除


按钮 我有更好的解析
按钮 我有更好的解析

题目讨论 (如果对题目有任何的疑惑,欢迎在这里提出来,大家会帮你解答的哦~)
总回复图标 发表讨论

  • 用户头像

    nimabi

    几周到底是长还是短,这篇文章真的是个哈麻皮
    3楼  | 2018-09-13 06:58:51 回复
  • 用户头像

    gmat是我前男友

    C项说的是实验室里的行为与自然状态下的行为没有差异。错误应该出在over the long term.
    2楼  | 2017-12-14 14:49:17 回复
  • 用户头像

    Angela1024

    C several weeks 应该不可以是long-term.
    1楼  | 2017-02-24 08:44:49 回复
    • 评论用户头像
      LOL666: 说得对!

      2017-12-22 19:02:10 回复

    •  
    提交
    标题图

    微信公众号:LGclub

    微信图

    Lindy老师:2095453331

    二维码
    • 手机注册
    • 邮箱注册
    登录>







    关闭图标

    标题图

    • 图标

      知识库学习

      GMAT语法、逻辑、阅读、数学各单项备考知识点学习及测验
    • 图标

      在线做题

      包含GMAT各单项必考知识点题目、OG/PREP/GWD/雷哥讲义题目、难度650/680/700/730题库题目练习及题目解析
    • 图标

      在线模考

      语文套题/数学套题/全套仿真模考,包含GWD/PERP/精选模考等上百套套题模考
    • 图标

      在线测评

      适合5种不同基础的GMAT学员,测评后可自动出具分数报告及复习计划指导
    • 图标

      资料下载

      GMAT必备备考资料下载、鸡精下载、课程课件等免费下载
    • 图标

      课程学习

      注册会员后,可在GMAT课程区,选择免费直播课程及公开课程进行在线学习
    ×
    请你选择你要查看的模考成绩单
    加载图片
    网络异常