如图表示人的双眼皮的遗传图解，请据图回答下列问题：（1）_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题解答题

如图表示人的双眼皮的遗传图解，请据图回答下列问题：

（1）人的双眼皮性状由______基因控制，单眼皮性状由______基因控制．

（2）控制双眼皮性状的一对基因位于______上，在形成生殖细胞时，这一对基因要随______的分开而分开，分别进入两个生殖细胞中．

（3）人的双眼皮和单眼皮这一对性状，我们将它们称为______．

（4）父母体细胞中的基因为Aa，则他们各产生两种生殖细胞，即______和______，比例为______．

答案

由于基因控制生物的性状，由于基因有显性基因和隐性基因，所以性状有显性性状和隐性性状．
（1）显性基因用大写字母表示，显性性状的基因组成为：AA或Aa；隐性基因用小写字母表示．隐性性状的基因组成为：aa．所以由图解可以看出，人的双眼皮是显性性状，是由显性基因控制的；单眼皮是隐性性状，是由隐性基因控制的．
（2）生物的性状是由基因控制的，基因位于染色体上，染色体在生物体细胞内是成对存在的，因此，基因也是成对存在的．在生殖过程中，亲代产生生殖细胞，染色体要减半，基因随之减半．染色体亲代的基因随着染色体传递给后代，并控制着后代的性状．
（3）相对性状指的是同种生物同一性状的不同表现类型，所以说人的单双眼皮属于相对性状．
（4）基因在生物的生殖过程中，体细胞内的基因到了生殖细胞中是要减半的，是分别进入精子和卵细胞内，比例：A：a═1：1．
故答案为：（1）A； a （2）一对染色体；染色体（3）相对性状（4）A a 1：1

完形填空

完形填空阅读短文，从每题所给选项中选出可以填入空白处的最佳选项（共15分；每空1分，满分15分）
When I was young，my father told me that little acts of kindness may give one great happiness. Since then I have always tried to help people in      .
One hot summer afternoon, I was               down the highway to New York when another car suddenly      into my lane(车道). My car was in the far right lane，so it ran onto the roadside. As a(n)      driver，I moved my car quickly and skillfully back onto the highway without causing any accident. I was      with that driver，but I thought that he just did not pay attention to（注意） the lane change, and he     did not do that on purpose(故意).The car ran away     after cutting me off. Very soon it disappeared from sight. After a while，I came around a curve(弯道) and found the    car. The driver was walking along the roadside. He was an elderly man and looked     . As there was no telephone nearby and the nearest services were twenty miles away, I decided to        and see what the problem was.
The man’s car had a flat tire(瘪胎). Although he had another tire，he had nothing to work with. I decided to     him. I changed the tire for him and allowed him to sit in my air-conditioned car while I did it. Fifteen minutes later，I      the work. I was hot and tired，but I really felt     after an act of kindness to the man who had earlier    my car run off the road.
You can really enjoy great   from kindness acts, so always lend your hands to others in trouble.

B．experienced

单项选择题

下列关于广东农村信用社股金转股票的基本规定，说法正确的一项是（）

A.农信社改制为农商行，可通过股金转股票交易将股金自动转为股票。

B.如未预先设定转换比例，则系统在转换日则按已设定的转换比例执行股金批量转股票。

C.如已预先设定转股比例，则系统在转换日则按资格股与投资股之和等额转换为股票。

D.未经客户确认转股的股金，不允许执行销户或退股等处理。