[問題]gwd8-33

[8妹]

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?


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

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

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

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

E. Until they are fully grown, horseshoe crabs shed their shells and grow new ones several times a year.[E]


粉不了這題到底是在......

[8妹]

自己推一下 8-|

[Jessy]

In order to withstand tidal currents, juvenile horseshoe crabs frequently burrow in the sand.(為了要抵擋海潮所必須burrow) Such burrowing discourages barnacles from clinging to their shells.(burrow可以讓barnacles不要附著在身上) When fully grown, however, the crabs can readily withstand tidal currents without burrowing,(長大的crab可以抵擋海潮-->排除海潮的原因) and thus they acquire substantial populations of barnacles.(照理說不burrow應該身上有粉多barnacles附著) Surprisingly(表示沒有附著), in areas where tidal currents are very weak, juvenile horseshoe crabs are found not to have significant barnacle populations, even though they seldom burrow.

問為何沒有barnacles會附在crab身上咧??


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

說明因為crab會脫殼, 所以附著在殼上的barnacles都被脫掉了.....

[8妹]

啊,我懂了,謝謝jessy

[lunar916]

D 哪裡不好呢?
能不能解釋說有殼太多的話會沒吃的,所以他們會分散

[michelle610]

題目說
為了要躲避海潮的波動,年輕的螃蟹挖地道,這樣一來一種寄生的東西b就沒辦法附著在螃蟹身上;但當螃蟹長大之後牠們就可以對抗海潮了,所以不挖洞了,這麼一來牠們身上應該就會有很多的b.但令人吃驚的是在海潮很弱的地方,年輕螃蟹不用挖洞去躲海潮,卻沒有很多的b在身上!!!

問怎麼解釋這個現象

所以D沒關吧!!!
D是說有很多的b會使的螃蟹覓食的能力降低,這和題目要問的沒啥關聯唷!!!

[seiis]

天啊 這題好難 = =單字一堆看沒有
=_=是不是我單字能力太弱了...
謝謝JESSY和MICHEELE 的解釋~!!

[Lory]

謝謝大大的解釋!!!

要成為大大真不容易!!!!

[hcgh]

D 哪裡不好呢?
能不能解釋說有殼太多的話會沒吃的,所以他們會分散

D只解釋了crab小時候沒有barnacle, 但無法解釋crab長大後卻招來一大堆barnacle.

[pinky9955487]

請問一下C是否否定前題呢?
題目說在潮汐很弱的地方,在螃蟹身上沒發現寄生蟲
C:我直接否定說潮汐的力量一天中根本不一樣

還是這題其實是要妳解釋這個現象所以選E
如果問題換成weaken的話,C可以嗎
謝謝解答

[dibert8]

這題有時覺得不可思議:
1.看到的蟹每一隻都在脫殼?
2.脫殼的時候就正好被這出題官給瞧見了?

[dibert8]

請問一下C是否否定前題呢?
題目說在潮汐很弱的地方,在螃蟹身上沒發現寄生蟲
C:我直接否定說潮汐的力量一天中根本不一樣

還是這題其實是要妳解釋這個現象所以選E
如果問題換成weaken的話,C可以嗎
謝謝解答

潮汐強弱好像找不到線索可以弱化,因為不管強弱,barnacle照樣附在蟹殼上.
這題似乎本身就是問弱化的原因.

有時覺得做CR遇到這樣的題目要有點背景知識,會比較好理解答案.

燒天然氣(methane)的那題(GWD6-32)也是,實際上的做法真的就是燒天然氣,儘管燃燒釋放二氧化碳.因為天然氣對溫室效應的貢獻是二氧化碳的27倍!

[hwatai]

這一題可以拿來鍛鍊「題目模模糊糊只懂個五成的情況下作答」

題幹是：
一個surprising現象：Ｂ這個東西沒有出現

(C)(D)分別為潮汐自然現象與覓食，較為無關的選項，可快速刪去

(B)要仔細看，有個關鍵字是readily，形容速度，原來是無關的資訊；另外最後有are weakest，也是一種錯誤選項資訊

(A)讀起來，像是通則性的概念，適合拿來解釋異常現象嗎？

迷迷糊糊還是要選(E)...培養對錯誤選項的感覺