Question

    Living with your parents has its benefits at least when it comes to raising your kids― their grandkids. Two new studies add to the evidence that grandmothers can enhance the survival of grandchildren. That is, unless grandma's too old or lives too far away.

Humans are unusual in that the females live long past the age at which they stop having babies. Patrick Bergeron, professor of biology at Bishop's University in Quebec, said that most of the organisms will reproduce up to their very last moment. This increase is often explained by the so-called "grandmother effect". He thinks there could still be a benefit for women who stop having babies to increase their genetic footprint by helping their daughters to raise larger families.

To explore the "grandmother effect" hypothesis （假设），Bergeron and his colleagues examined nearly 200 years' worth of French-Canadian population records from the 17th and 18th centuries. "At the time, life was tough. In some years, a third o£ the kids were not even making it to one year of age.” But the researchers found that having a grandmother still alive was a definite plus."Families with grandmothers alive were larger by about two and the survival of these grandchildren to age 15 was much improved."

This beneficial effect was only seen when the matriarchs （女家长）lived nearby. That role is tougher for them to fulfills as they get older in poor health, which brings us to the second study. The researchers found that the benefits associated with having a grandmother on hand depended on her age. Once manna hit 75, the grandchild survival benefit disappeared. This was almost certainly due to some form of indirect resource competition, though, rather than wickedness （邪恶）on the part of co- resident grandmothers.

So a healthy grandma helps make for a healthy grandchild. If ',over the river and through the woods to grandmother's house" isn't too long a trip.

1.What's the second paragraph mainly about?

A.Differences between animals and human beings.

B.Disadvantages of living with grandmas

C.Grandmothers' influence on the kids.

D.What's called“grandmother effect”.

2.How does the writer describe about the French-Canadian population more than three hundred years ago?

A.By voicing opinions. B.By providing facts.

C.By giving examples. D.By telling stories.

3.What can we infer from the second study?

A.Society should be concerned about the old women.

B.Grandmothers over 75 years old are unwilling to help.

C.Some grandmothers may occupy kids' relative recourses.

D.Some grandmothers are getting wicked after they are old.

4.Which of the following can be the most helpful grandmother according to the passage?

A.A healthy one living nearby. ,

B.A healthy one living abroad.

C.An old one living in a nursing home.

D.A knowledgeable one living together.

Answer

1.D

2.B

3.C

4.A

【解析】

本文为议论文。文章论述了什么是“祖母效应”，以及“祖母效应”对子孙辈的好处。

1.主旨大意题。分析第二段的内容可知，本段主要叙述了人类的不同寻常之处在于，雌性的寿命远远超过了停止生育的年龄。大多数生物会一直繁殖到生命的最后一刻。Patrick Bergeron，魁北克Bishop大学的生物学教授说。生育后寿命的延长通常可以用“祖母效应”来解释。他认为，对于那些停止生育的女性仍然可以通过帮助女儿组建更大的家庭来增加她们的基因足迹。由此可知，本段主要对于什么是“祖母效应”进行了解释和说明。故本题选D。

2.推理判断题。第三段Bergeron and his colleagues examined nearly 200 years' worth of French-Canadian population records from the 17th and 18th centuries. "At the time, life was tough. In some years, a third of the kids were not even making it to one year of age.” But the researchers found that having a grandmother still alive was a definite plus. "Families with grandmothers alive were larger by about two and the survival of these grandchildren to age 15 was much improved." Brgeron和他的同事研究了17和18世纪(三百多年前)近200年的法裔加拿大人口记录。当时的生活很艰难。那些年里三分之一的孩子甚至活不到一岁。但研究人员发现，有一位仍然健在的祖母无疑是一个优势。“有祖母的家庭可能要多活两岁左右，这些孙辈活到15岁的几率大大提高”由此可知，本段以三百年前的法裔加拿大人的事实（具体的数据）为依据说明有祖母的好处。故选B 。

3.推理判断题。根据第四段... The researchers found that the benefits associated with having a grandmother on hand depended on her age. Once manna hit 75, the grandchild survival benefit disappeared. This was almost certainly due to some form of indirect resource competition, ... 研究人员发现，有祖母在身边的好处取决于她的年龄，一旦祖母到了75岁，孙辈的生存福利就消失了。 这几乎可以肯定是由于某种形式的间接资源竞争。由此可推断出，当祖母老了，有些祖母可能会占用孩子相关的资源。分析选项可知C项符合题意，故选C。

4.推理判断题。根据最后一段So a healthy grandma helps make for a healthy grandchild. If ',over the river and through the woods to grandmother's house" isn't too long a trip.”所以一个健康的奶奶有助于一个健康的孙子。如果“过河穿过树林到外婆家”不是一次很长的旅行。文事的“过河穿过树林到外婆家”意味着离外婆家不远。由以上的内容可推断出，一个健康的且住在附近不远的祖母对于一个健康的孙子来说很有帮助。故选A。