水洗型着色检验是指零件表面（）能直接用（）洗掉

In recent years a new farming revolution has begun, one that involves the (1) of life at a fundamental level-the gene. The study of genetics has (2) a new industry called biotechnology. As the name suggests, it (3) biology and modern technology through such techniques as genetic engineering. Some of the new biotech companies specialize in agriculture and are working feverishly to (4) seeds that give a high yield, that (5) disease, drought and frost, and that reduce the need for (6) chemicals. If such goals could be achieved, it would be most (7) . But some have raised concerns about genetically engineered crops.

In nature, genetic diversity is created within certain (8) . A rose can be crossed with a different kind of rose, but a rose will never cross with a potato. Genetic engineering (9) usually involves taking genes from one species and inserting them into another (10) to transfer a desired characteristic. This could mean, for example, selecting a gene which leads to the production of a chemical with anti-freeze (11) from an arctic fish, and inserting it into a potato or strawberry to make it frost-resistant. (12) , then, biotechnology allows humans to (13) the genetic walls that separate species.Like the green revolution, (14) some call the gene revolution contributes to the problem of genetic uniformity-some say even more (15) geneticists can employ techniques such as cloning and (16) culture, processes that produce perfectly (17) copies. Concerns about the erosion of biodiversity, therefore, remain. Genetically altered plants, however, raise new (18) , such as the effect they may have on us and environment. ".We are flying blindly into a new (19) of agricultural biotechnology with high hopes, few constraints and little idea of the potential (20) ," said science writer Jemery Rifkin.

4（）

A．hatch

B．train

C．duplicate

D．patent

用成轴对称的汉字写出一个词组______．

可作为等渗调节剂的是

A．甲基纤维素
B．氯化钠
C．三氯叔丁醇
D．焦亚硫酸钠
E．EDTA钠盐

举例说明3种动物采血实验方法

渗出液的特点有( )

A．蛋白含量高

B．比重低

C．细胞成分多

D．液体清亮

E．细胞成分少