填空题为保护酶的活性，对以巯基为活性基团的酶应添加______；对以Asp为活性基团的酶应添加______。

填空题The volcano in the cornfield grew until it was bigger than the cornfield! (41)______ People called the volcano the Little Monster because it grew so fast. Scientists came from all over the world to study it and watch it grow. It is not often that people get a chance to watch a volcano from the very beginning. Most of the volcanoes have been here for a very long time. Some have been here so long that now they are cold. They are called dead volcanoes. They have stopped throwing out fire and melted rock and smoke. It is safe to walk on them. Farms are plowed on the quiet slopes, and people have built houses there. Some volcanoes have stopped throwing out hot rock, but they still smoke a little now and then. They are "sleeping" volcanoes. Sometime they may "wake up". (42)______. Today volcanoes are not so dangerous for people as they were a long time ago. Now we know more about why volcanoes do what they do, and we can usually tell when they are going to do it. (43)______. People used to think dragons under the earth caused volcanoes. They said the smoke that puffed above the ground was the dragon's breath. They said the earthquakes were caused by the dragon's moving around down in the earth. Now we know that this is not true. Another thing we know about volcanoes is that they don't happen just anywhere. (44)______. Scientists know where these places are, and maps have been made to let everybody know. There are different kinds of volcanoes. Some explode so violently that the rock goes high into the air and falls miles away. A volcano may shoot out ashes so high that they float all the way around the world. They have made the sunsets green and the snow purple. (45)______. One very tall volcano stays fiery red at the top all the time. It is lucky that the volcano is near the ocean. Sailors can use it for a lighthouse. [A] Other volcanoes are more gentle. The hot lava rises in their cones and overflows, rolling slowly down the mountainside, where it becomes cool and hard. [B] Black smoke puffed out. Hot ashes fell like black snowflakes. Hot rock and fire and lava shot out. [C] Smoke puffed up, and rock started popping up out of a crack that opened in the ground. [D] A volcano named Vesuvius slept for a thousand years. But it woke up and threw out so much hot melted rock that it buried the buildings of two cities. [E] Before a sleeping volcano wakes up, it usually makes a noise like faraway thunder, and the ground shakes in small earthquakes. People are warned and have time to get away safely. [F] A volcano starts from a hole in the ground from which hot rock and smoke and steam come out. Far, far under the ground it is so hot that rock melts. This hot melted rock, or lava, is some-times pushed out of the earth through a hole or a crack in the ground. The steam inside the earth pushes the rock out. [G] There are certain places under the earth where the rock is broken in a way that lets the steam and hot rock escape to the outside more easily.

填空题第一个被解析出晶体结构的蛋白是______。

填空题一个完整的病毒颗粒是由______和______组成。

填空题从真核生物mRNA前体中切除内含子，将外显子连接的过程被称为______。

填空题YAC的功能性元件，包括______、______和______。

填空题写出两种合成后不被切割或拼接的RNA：______和______。

填空题λ噬菌体由于包装的限制，插入外源DNA片段后，总长度应在噬菌体基因组的______范围内。

填空题在下列描述词后面填上合适的化学键： (1)连接核糖和磷酸的____键。 (2)在两条DNA链间搭桥的_____键。 (3)连接碱基和糖的_____ 键。 (4)在RNA中连接核苷酸的_____键。

填空题两个基因在______上的距离的数量单位称为图距。1%重组值去掉其百分率的数值定义为一个图距单位，后人为纪念现代遗传学的奠基人______，将图距单位称为______。

填空题常用的酶活力测定方法有______、______和______°

填空题经过转录后加工的所有tRNA的3"端都含有______序列。

填空题如果刚制备的质粒DNA样品的A260/A280＞1.6，那么该样品可能受到______污染。

填空题当倒位杂合体自交后，其后代将产生①______，②______，③______三种类型，其比例为______。

填空题真核生物的mRNA 5'端常有______结构，第一个核苷酸总是______。

填空题在蛋白质结构测序中，对肽链进行部分水解具有相应的要求，除了要求反应产率高以外，还必须强和______少。

填空题1%重组值(交换值)=______个图距单位=______cM(厘摩)

填空题重组子的筛选有两层含义，一是______；二是______。

填空题组成蛋白质的20种氨基酸中，侧链pK值接近中性的氨基酸是______，无游离/自由氨基的氨基酸是______。

填空题大肠杆菌DNA聚合酶Ⅰ的三种酶活性分别是______、______和______。