GWD2 2 :I suspect I am right!!!

xinfaxian

顶！！！查了一下这篇3个答案好乱呀！到底应该是什么呀？EBD or DBC?

还有想请教一句话的意思，看了半天也不明白，尤其是黄色的部分，谁是这句的主语啊？

请哪位帮忙看一下？谢谢了。

It might seem that certain traits would clearly define a species as a keystone species; for example, Pisaster ochraceus is often a keystone predator because it consumes and suppresses mussel populations, which in the absence of this starfish can be a dominant species.  

[此贴子已经被作者于2005-6-1 15:18:59编辑过]

而今迈步从头越

I vote for EBD.

It might seem that certain traits would clearly define a species as a keystone species; for example, Pisaster ochraceus is often a keystone predator because it consumes and suppresses mussel populations, which in the absence of this starfish can be a dominant species.

帮MM翻译这句话啊：有某些特性能够清晰的确定一个物种为keystone物种。比如说，Pisaster ochraceus 经常是keystone物种的捕食者，因为PO食用贝类，抑制贝类的生长，而这些贝类在这种海星(PO)不出现的时候是一个dominant物种。

which指的是mussel populations，this starfish指的是Pisaster ochraceus .

xinfaxian

贴出来了，麻烦Tony nn 帮忙看一下，谢谢。

Question 2:  The primary purpose of the passage is to

A.      point out some of the differences between dominant and keystone species

B.      emphasize the complexity of the interactions that occur between two particular species

C.      detail the effect of a particular habitat on the role occupied by a certain keystonspecies

D.     illustrate the importance of community diversity for the perpetuation of an ecosystem

E.      explain some considerations involved in determining whether a species occupies a keystone role

Question 3:

Which of the following, if true, would most clearly support the argument about keystone

status advanced in the last sentence of the passage (lines 15 – 19)?

A.      A species of bat is primarily responsible for keeping insect populations within an

ecosystem low, and the size of the insect population in turn affects bird species

within that ecosystem.

B.      A species of iguana occupies a keystone role on certain tropical islands, but does

not play that role on adjacent tropical islands that are inhabited by a greater number

of animal species.

C.      Close observation of a savannah ecosystem reveals that more species occupy

keystone roles within that ecosystem than biologists had previously believed.

D.     As a keystone species of bee becomes more abundant, it has a larger effect on

the ecosystem it habits.

E.      A species of mouse that occupies a keystone role in a prairie habitat develops

coloration patterns that camouflage it from potential predators.

Question 4:

The passage suggests which of the following about the identification of a species as

a keystone species?

A.      Such an identification depends primarily on the species’ relationship to the dominant species.

B.      Such an identification can best be made by removing the species from a particular

ecosystem and observing changes that occur in the ecosystem.

C.      Such an identification is likely to be less reliable as an ecosystem becomes less diverse.

D.     Such an identification seems to depend on various factors within the ecosystem.

E.      Such an identification can best be made by observing predation behavior.

xinfaxian

以下是引用而今迈步从头越在2005-6-1 16:02:00的发言：

I vote for EBD.

It might seem that certain traits would clearly define a species as a keystone species; for example, Pisaster ochraceus is often a keystone predator because it consumes and suppresses mussel populations, which in the absence of this starfish can be a dominant species.

帮MM翻译这句话啊：有某些特性能够清晰的确定一个物种为keystone物种。比如说，Pisaster ochraceus 经常是keystone物种的捕食者，因为PO食用贝类，抑制贝类的生长，而这些贝类在这种海星(PO)不出现的时候是一个dominant物种。

which指的是mussel populations，this starfish指的是Pisaster ochraceus .

谢谢而今迈步从头越mm的翻译哦，看懂了。估计上午是脑子灌水了，怎么会没看懂涅？郁闷啊！还有十来天就要考的人了。。。

keepforward

严重同意而今迈步从头越班主的最后选项 EBD，其他答案完全不合理。

只是疑惑为何这片阅读的讨论不在讨论汇总中列出，吓我一身冷汗！寒！

建议斑竹补充到汇总中。 谢了！

susan-susan

agree   E B D

yukon

今天刚做，支持EBD

yahoow

还是觉得GWD2-4答案选C。“The passage suggests which of the following about the identification of a species as a keystone species?

”，从这句“(for example, a reduction in species diversity may thrust more of the remaining species into keystone roles)，支持了C的说法：Such an identification is likely to be less reliable as an ecosystem becomes less diverse.

欢迎继续讨论。

wangyu73cn

对于第2题，支持E。全文应该是贯穿这一主题的。
C选项是说，“对于特定栖息地点之于'keystone'物种功能的影响，进行详细地阐述。”此选项应该不是文中的主线，仅仅是一种细节论述。

[此贴子已经被作者于2005-7-6 23:11:36编辑过]

yahoow

同意第2题答案为E。版主帮我看看第4题选哪个？今天阅读练习全部结束了，明天练习作文了。好累！今晚好好睡一觉。