Question

    Did you know people who live in different parts of China have different habits and preferences? For example, people from southern China prefer to eat vegetables, while people from north China like to eat meat. According to a new study in a journal, gene variations (基因变异) might be responsible for these differences. Researchers from China’s BGI collected genetic information from 141, 431 Chinese women, who came from 31 provinces and consisted of 36 ethnic minority groups.

The researchers found that there are six gene frequencies that are different among people from both northern and southern China. They found that natural selection has played an important role in the ways that people living in different regions of China have developed, affecting their food preferences, immunities(免疫力)to illness and physical features.

A variation of the gene FADS2 is more commonly found in northern people. It helps people metabolize (新陈代谢) fatty acids, which suggests a diet that is rich in flesh. This is due to climate differences. Northern China is at a higher latitude. This weather is difficult to grow vegetables in. Therefore, northerners tend to eat more meat.

The study also found differences in the immune systems of both groups. Most people in southern China carry the gene CR1, which protects against malaria. Malaria was once quite common in southern China. In order to survive, the genes of people in the south evolved to fight against this disease. However, people in the south are also more sensitive to certain illnesses, as they lack the genes to stop them.

Genes can also cause physical differences between northerners and southerners. Most northerners have the ABCC11 gene, which causes dry earwax, less body smell and fewer sweats. These physical differences are also more beneficial to living in cold environments. Southerners are less likely to have this gene, as it did not develop in their population.

1.What did the new study focus on?

A.Regions. B.Vegetables.

C.Gene variations. D.Ethnic minority groups.

2.What is the main function of the gene FADS2?

A.It helps store fat. B.It helps digest meat.

C.It helps gain weight. D.It helps treat illness.

3.According to the study, most northerners ______.

A.are immune to malaria B.catch blood-borne illnesses easily

C.have no body smell D.sweat less frequently

4.How many differences did the study find related to genes?

A.Two. B.Three.

C.Four. D.Five.

Answer

1.C

2.B

3.D

4.B

【解析】

这是一篇说明文。文章主要讲了南方人喜欢吃蔬菜，而北方人喜欢吃肉。根据杂志上的一项新研究，基因变异可能是造成这些差异的原因。

1.细节理解题。根据第一段According to a new study in a journal, gene variations (基因变异) might be responsible for these differences.（根据杂志上的一项新研究，基因变异可能是造成这些差异的原因。）由此可知，新研究的重点是基因变异。故选C。

2.细节理解题。根据第三段A variation of the gene FADS2 is more commonly found in northern people. It helps people metabolize (新陈代谢) fatty acids, which suggests a diet that is rich in flesh.（FADS2基因的变异更常见于北方人。它帮助人们代谢脂肪酸，这就表明饮食中要有丰富的肉类。）由此可知，FADS2基因的主要功能是帮助消化肉类。故选B。

3.细节理解题。根据最后一段Most northerners have the ABCC11 gene, which causes dry earwax, less body smell and fewer sweats. These physical differences are also more beneficial to living in cold environments. （大多数北方人都有ABCC11基因，这种基因会导致耳垢干燥，体臭少，出汗少。这些生理上的差异对生活在寒冷的环境中也更有利。）由此可知，根据这项研究，大多数北方人出汗较少。故选D。

4.推理判断题。根据第三段A variation of the gene FADS2 is more commonly found in northern people.（FADS2基因的变异更常见于北方人）和第四段Most people in southern China carry the gene CR1, which protects against malaria.（中国南方的大多数人都携带有抗疟疾的CR1基因）以及第五段Most northerners have the ABCC11 gene, which causes dry earwax, less body smell and fewer sweats.（大多数北方人都有ABCC11基因，这种基因会导致耳垢干燥，体臭少，出汗少）由此可知，这项研究发现了三种与基因相关的差异。故选B。