填空题许多动物的倒位纯合体有致死作用；而倒位杂合体有降低育性趋势，表现为______。

填空题大肠杆菌F + 菌株与F - 菌株结合，最后F + 菌株变成了______，F - 菌株变成了______。

填空题易位杂合体在减数分裂后期Ⅰ，出现了O型大环，他将产生配子的类型是______，他们育性表现是______。

填空题在互补测验中，两个突变型若表现出互补效应，则证明______；若不能表现出互补，则证明______。

填空题In February of 1997 Dolly, the first successful mammalian clone, was born in Edinburgh, Scotland. With the extensive news coverage of this momentous event, the study of genetic engineering and recombinant DNA was thrown into the public spotlight. (41)__________Much of this unfounded fear is based upon memories of poorly researched science fiction novels, fear of the unknown, and a "growing mistrust of science". (42)__________For example, it will be possible for cows to be genetically engineered to produce pharmaceuticals in their milk. This means that vaccination shots and pills would become obsolete. Babies could be brought up immune to diseases by simply being fed this milk. Imagine the impact on the quality of life for people who live in third world countries like Somalia. Whole countries could be made healthy and immune to disease. (43)__________Rice does not provide all of the nutrients that the body needs and in these countries other food is very scarce. If rice or bread, another major staple, are genetically engineered to contain additional necessary vitamins and minerals then we could go a long way towards wiping out malnutrition all over the world. (44)__________Organ transplants and cosmetic procedures, like silicone breast implants, that may cause disease would soon cease to exist. Instead of using materials foreign to the body for such procedures, doctors will be able to manufacture bone, fat, connective tissue, or cartilage that match the patient's tissues exactly, thus ensuring that the needed tissue will be free of rejection by their immune system. Victims of terrible accidents that deform the face and body would be able to have their features repaired with new, safer technology. (45)__________ Throughout time people have always been afraid of new technology and the power it might possess. When the car was first invented some contemporary scientists were convinced that the human body could not survive at speeds as high as twenty miles per hour. At one time birth control pills, in vitro fertilization, and heart transplants were criticized on the same grounds. Genetic engineering is an extremely new aspect of our technological research and should, at all costs, be allowed to develop further. The immense possible benefits from genetic engineering are endless and should not be overlooked. Genetic engineering, then, is a tool that humans can use to cure many of their problems. [A] Even though the risks are great, the beneficial possibilities are endless. Genetic engineering should be allowed to progress because of the potential benefits for the human species outweigh the consequences. [B] Scientists are only beginning to explore the dangers and benefits of genetic engineering. Yet, instead of seeing the immense potential benefits, much of the American public is automatically rejecting this field of research. [C] Genetic engineering also has the power to cure infertility, which a painful reality that many couples throughout the world face. [D] Even with all these miraculous benefits, many people throughout the world feel that the issue of genetic engineering is absolutely preposterous and extremely unethical. Such opinions are understandable, considering that the majority of people are always going to be afraid of the unknown. [E] Malnutrition, a common problem in many third world countries where impoverished peoples rely on a single crop such as rice for the main staple of their diet, could also possibly be cured with genetic engineering. [F] But perhaps, the area that stands to benefit the most from genetic engineering is medicine. [G] Genetic engineering is like performing heart surgery with a shovel. Scientists do not yet understand living systems completely enough to perform DNA surgery without creating mutations which could be harmful to the environment and our health.

填空题遗传的基本原理是由______揭示的，其遗传理论的精髓是______学说。主要内容为：______。

填空题玉米相互易位杂合体______式分离产生的配子全部可育。

填空题比较______构型的细胞的表型从而判断______的测验，称顺反位置效应测验，这种互补作用是______之间的互补作用，所以也称______互补。

填空题绘制遗传学图时，基因定位所采用的主要方法有两种，即______和______。

填空题一般来讲，近亲婚配可以提高常染色体______遗传病的发病率。

填空题人类的性别决定属于______型，鸡的性别决定属于______型，蝗虫的性别决定属于______型。

填空题红色面包霉生长缓慢型，酵母小菌落，放毒型草履虫，都属于细胞质遗传，细胞质基因的载体分别是______、______、______。

填空题在Briggs和King对豹蛙去核的未受精卵进行核移植的实验中发现，用个体发育的______以前时期的核移入去核卵细胞，其发育成正常蛙的个体比率可高达100%，用______以后时期的核，成功率为77%。

填空题环境变化突然使一种隐性等位基因完全致死。要使它的频率从10 -2 减少到10 -3 ，这将经过______代。

填空题父母之一方是AB血型，另一方是O血型，其子女既可能是______血型，也可能是______血型。

填空题具有四对等位基因(AaBbCcDd)的一杂合植株，进行自花授粉后出现aabbccdd后代的频率是______，aabbCcDd和AaBbCcDd的频率分别是______和______。

填空题当F + 或Hfr细菌染色体进入F - 后，在一个短时期内，F - 细胞中对若干基因座来说总有一段______体的DNA，这样的细菌称为______。

填空题链孢霉的缓慢生产突变型是因为在______上发生基因突变造成的。

填空题分离定律的实质在于形成配子时______彼此分离，自由组合定律的实质在于形成配子时______彼此自由组合。受精时雌雄配子______结合。

填空题线虫的______个细胞进入程序性死亡至少有______个基因在起作用，被定名为______基因。其中______和______为正调控基因，______是细胞死亡的负调控基因。