《2024年绿色通道45分钟课时作业与单元测评英语选择性必修第三册》

                                                                            A
(2024.四川成都高二练习)People are motivated to try a vegetarian(素食的) diet for different reasons−from ethical and religious, to potential health and environmental benefits. But many people have a hard time sticking to it. In fact, studies show many self−reported vegetarians actually do consume some animal products.
“A lot of people who want to be vegetarian are perhaps not able to,” says Dr Nabeel Yaseen, of Northwestern University Feinberg School of Medicine. “We wanted to know if genetics(遗传学) is part of the reason,” he says.
Yaseen and his team members compared the DNA of about 330,000 people. They found 34 genes(基因) that may play a role in sticking to a strict vegetarian diet. And they identified 3 genes that are more tightly linked to the feature.
“What we can say is that these genes have something to do with vegetarianism,” Yaseen says. “Perhaps vegetarians have different variants(变体) of these genes that make them able to choose a strict vegetarian diet,” he explains. The study is published in PLOS ONE, a peer−reviewed science journal.
Interpreting the genetic role is not exactly an easy task to finish. Humans have thousands of genes and there are millions of tiny variations in DNA building blocks, known as single nucleotide polymorphisms(SNPs), where you can see differences between individuals.
To identify SNPs that are connected with the particular feature of sticking to a vegetarian diet, Yaseen and his workmates did a genome−wide connection study. When they found a SNP connected with vegetarianism, they looked to see the genes around it in the same area.
Of the three genes most strongly connected with vegetarianism, the authors say two of them (known as NPC1 and RMC1) have important functions in lipid−or fat−metabolism. The study can't answer exactly how genetic differences could shape or influence vegetarians, but Dr Yaseen has some ideas. His research has disclosed many unknown aspects of genetics.

1. Why did Dr Nabeel Yaseen research vegetarians?
A. To understand health benefits of vegetarianism.
B. To investigate genetics in vegetarian devotion.
C. To study environmental impact of vegetarianism.
D. To explore the cultural aspects of vegetarianism.
2. What can we learn about genes from Yaseen's study?
A. They have the same variations.
B. They determine vegetarian fat.
C. They may influence vegetarianism.
D. They play no role in dietary choices.
3. What is the author's attitude to Yaseen's findings?
A. Critical.
B. Appreciative.
C. Unconcerned.
D. Doubtful.
4. What is the best title for the text?
A. The Benefits of Vegetarianism
B. The Diet Research on Vegetarians
C. Challenges in Maintaining a Vegetarian Diet
D. The Role of Genetics in Vegetarian Devotion

答案： 1.B 细节理解题。根据第二段中的“A lot of people who want to be vegetarian are perhaps not able to”和“We wanted to know if genetics (遗传学) is part of the reason”可知，纳比尔·亚瑟恩博士研究素食主义者是为了调查基因是否对人们热爱吃素食有影响。故选B。
2.C 推理判断题。根据第三段中的“They found 34 genes (基因) that may play a role in sticking to a strict vegetarian diet. And they identified 3 genes that are more tightly linked to the feature.”和第四段第一句可推知，有些基因可能影响素食主义。故选C。
3.B 推理判断题。根据最后一段中的“The study can’t answer exactly how genetic differences could shape or influence vegetarians, but Dr Yaseen has some ideas. His research has disclosed many unknown aspects of genetics.”可知，虽然研究目前无法准确解释基因与素食者之间的关联，但是作者肯定了亚瑟恩博士的研究，认为它揭示了遗传学的未知面。由此可推知，作者对其研究发现持欣赏、赞许的态度。故选B。
4.D 标题归纳题。通读全文，尤其是根据第二段中的“We wanted to know if genetics (遗传学) is part of the reason”可知，文章围绕为什么有些人无法坚持素食主义展开，通过一项研究揭示了有些基因可能与能否坚持严格素食饮食有关。因此，D项“基因在热爱素食中的作用”契合文章大意，最适合作为本文标题。故选D。