新视野大学英语视听说教程 4 Unit 8-3

Task 2: The Improvement of Rice
Script      
Scientists now know a lot more about a grain that people have eaten for ten thousand years. (S1) Research teams around the world have completed a map of the (S2) genes¹ of rices. The findings appeared last week in the (S3) journal Nature.
The aim is to speed up the improvement of rice. The scientists (S4) warn that the kinds of rice plants used now have reached the limit of their (S5) productivity. Yet world rice production must (S6) grow by an estimated 30 percent in the next twenty to meet demand. By 2025, as many as 4.6 billion people will depend on rice for (S7) survival. There is a lot of pressure on breeders to improve the crop, and the rice genome is a valuable tool to do that. (S8) Plant breeders have already used preliminary information from the rice genome to create experimental strains of rice that better resist cold and pests.
The researchers also say rice is an excellent choice for genetic² mapping and engineering. Rice genes have only about 390 million chemical bases. That maight sound like a lot. But other major food grains have thousands of millions. (S9) The new map could better explain more than just rice. Rice shares a common ancestor with other cereal crops. Because rice is the first cereal crop to be fully³ analyzed⁴, researchers expect that sufficient knowledge of its genetic information will reveal the heredity of more complex grains, including corn, wheat and barley⁵.
(S10) While significant progress has been made in the analysis of the rice genome, the mapping of human genes is also making headway. When scientists can identify and manipulate genes that cause certain diseases, mankind will cure them easily. The human genetic map may help us control a person’s height, weight, appearance and even length of life.

1 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪

2 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

3 fully   

adv.完全地，全部地，彻底地；充分地

参考例句：

• The doctor asked me to breathe in,then to breathe out fully.医生让我先吸气，然后全部呼出。
• They soon became fully integrated into the local community.他们很快就完全融入了当地人的圈子。

4 analyzed   

v.分析( analyze的过去式和过去分词 )；分解；解释；对…进行心理分析

参考例句：

• The doctors analyzed the blood sample for anemia. 医生们分析了贫血的血样。 来自《简明英汉词典》
• The young man did not analyze the process of his captivation and enrapturement, for love to him was a mystery and could not be analyzed. 这年轻人没有分析自己蛊惑著迷的过程，因为对他来说，爱是个不可分析的迷。 来自《简明英汉词典》

5 barley   

n.大麦，大麦粒

参考例句：

• They looked out across the fields of waving barley.他们朝田里望去,只见大麦随风摇摆。
• He cropped several acres with barley.他种了几英亩大麦。