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题库 / Prep2007E1-CR-64
Adult female rats who have never before encountered rat pups will start to show maternal behaviors after being confined with a pup for about seven days. This period can be considerably shortened by disabling the female's sense of smell or by removing the scent-producing glands of the pup.
Which of the following hypotheses best explains the contrast described above?
The sense of smell in adult female rats is more acute than that in rat pups.
The amount of scent produced by rat pups increases when they are in the presence of a female rat that did not bear them.
Female rats that have given birth are more affected by olfactory cues than are female rats that have never given birth.
A female rat that has given birth shows maternal behavior toward rat pups that she did not bear more quickly than does a female rat that has never given birth.
The development of a female rat's maternal interest in a rat pup that she did not bear is inhibited by the odor of the pup.
推理1：没有怀孕的母老鼠 + 刚出生的小老鼠——> 有母性行为出现
推理2：出现母性行为的没有怀孕的母老鼠+去掉这些母老鼠的嗅觉+去掉小老鼠的腺体——>母性行为的时间缩短
问题问的是，推理1和推理2之间的gap在哪里？（为什么推理1和推理2两件事情都会发生）
所以当然是E啦：因为让母老鼠产生母性行为的核心原因是小老鼠的味道Odor，所以当科学家将母老鼠的嗅觉除掉，以及把小老鼠排汗的腺体去掉，母老鼠就闻不到小老鼠的味道，因此就会缩短shortern 母性泛滥的时间了
屏蔽成年母鼠的嗅觉→它出现maternal behaviors（MB）的时间缩短
A、成年母鼠的嗅觉比幼鼠灵敏，无关对比
B、当出现在不是亲生母亲的母鼠面前，幼鼠散发的气味更多，无关对比
C、生过宝宝的母鼠嗅觉比没生过的更灵敏，无关对比
D、对于非亲生孩子，生过宝宝的母鼠比没生过的更快展现MB，无关对比
E、母鼠通过气味辨别孩子，CORRECT（所以如果嗅觉屏蔽，它就认不出自己的孩子了）
E正确描述母鼠的母性行为受幼鼠的气味影响
那么不出来的时候，就可能受到味道的抑制
---by ruqi
没有生育过的母鼠在和幼崽相处7天之后会展现出母性行为，这个时间可以大大缩短通过disable母鼠的嗅觉或者移除幼崽身上产生气味的腺
说明母鼠的母性和幼崽的气味有关
e：The development of a female rat's maternal interest in a rat pup that she did not bear is inhibited by the odor of the pup.
inhibited抑制的
hypotheses: 母鼠对于一个不是亲生的幼崽的兴趣被幼崽的气味所抑制了
但凡出现了幼崽的亲生母鼠的选项都可以rule out~
做题一定要主动！理解题目一定要灵活！！（这样理解不了就赶紧换一个方向去理解，不要死磕，要学会自己补充意思）
gland 腺
scent 气味
这个时间能大量缩短通过 1使female感觉smell失效，2除去pup scent的产生 →都是和气味scent有关（答案要有这个才是explain）
A：The sense of smell只提了female的没有说pup，不能对比
B：The amount of scent produced by rat pups 增加，那就和出去scent能缩短时间矛盾
C&D：文中没有前后对比given birth前后
E：母性行为兴趣的发展是源于pup的气味，符合
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