您所在的当前位置：初中生物试题 >

人的性别遗传

> 已知有耳垂（Ｄ）对无耳垂（ｄ）是显性。某同学无耳垂，但他的父母都有耳垂，则该同学父母的基因型分别是（） A.Dd，Dd B.DD,DD C.DD,Dd D. Dd,DD

问题：

发布时间：2024-09-07

已知有耳垂（Ｄ）对无耳垂（ｄ）是显性。某同学无耳垂，但他的父母都有耳垂，则该同学父母的基因型分别是（）
A.Dd，Dd B.DD,DD C.DD,Dd D. Dd,DD

参考答案：

提问用户：rI***JBg

可能感兴趣的题目：

1 下列词语中加点的字，读音全都正确的一项是（） A．翘qiáo首裨bì益擘bò划锐不可当dāng B．蚊蚋nà侪chái辈道行háng呼天抢qiāng地 C．肄yì业霰xiàn雪干gàn犯教学相长zhǎng D．胡诌zhōu皈guī依神衹zhǐ盛筵yàn难再
2 【题文】肾脏结构和功能的基本单位是，神经系统结构和功能单位是神经调节的基本方式是，其结构基础是。
3 如图所示的两个虚线框内分别填入电源或开关的符号，并满足闭合任何一个开关都能使小灯泡L发光．
4 如图所示为 _________ 眼的成因光路图，请在虚框内画出矫正视力的透镜．
5 Finland is a great country to visit, especially for relaxing. You can easily find peace and quiet there because much of the country is covered with forests. It also has lots of hills and thousands of lakes and islands. Depending on the season, visitors can enjoy themselves in bird-watching, hiking, fishing and other outdoor activities. There is even a part of Finland where people can see the beautiful Northern lights. If you are a nature lover, you will discover plenty to enjoy in Finland. You will also find that the people of Finland are easy-going. This might be because they spend a lot of time having a sauna（桑拿）to relax themselves together. Finland even has a competition that is about spending time in one sauna. In the Sauna World Championships, people try to stay as long as they can in a sauna. This is really a hot competition! Finland is always considered as one of the best places in the world to live in, from its capital, Helsinki, to its great number of lakes and forests. Finland is truly one of the world’s greatest treasures. 小题1: Forests much of Finland. 小题2: Depending on the season, visitors can in bird-watching, hiking, fishing and other outdoor activities. 小题3: The people of Finland are relaxing and . 小题4: is a popular way for people to relax themselves in Finland. 小题5: Because of the capital of Finland and its lakes and forests, Finland is considered as one of in the world to live in .
6 ---Can you ____them _____France? ---No, I can’t. I only speak Chinese and English A．speak; in B．say; in C．speak; with D．tell ;in
7 新疆地区正式隶属中央政府管辖开始于 [ ] A、汉高祖时 B、汉武帝时 C、汉宣帝时 D、汉光武帝时
8 已知数列{a n}的各项均为正数，其前n项和是S n，若[log 2a n]是公差为-1的等差数列，且 S6= 3 8 ，那么a 1的值是（　　） A． 4 21 B． 6 31 C． 8 21 D． 12 31
9 （1）请观察两个保温瓶的温度计读数，其中甲瓶装的是萌发的种子，乙瓶装的是煮熟的种子：甲瓶的读数______（较高/较低）．乙瓶的读数______（较高/较低）．说明：萌发的种子释放出______，这是种子中的______被分解释放出来的．澄清的石灰水变浑浊说明种子萌发时分解有机物产生了______气体．（2）把正萌发的小麦种子放入干燥的塑料袋中扎进，放到光下一段时间后，塑料袋内壁会出现______，说明种子萌发时分解有机物产生了______．结论：有机物被彻底分解时产生了______和______．（3）甲瓶装萌发的绿豆种子，乙瓶装有等量煮熟的绿豆种子，把点燃的蜡烛放入瓶中，甲瓶蜡烛______（燃烧、熄灭）；乙瓶蜡烛______（燃烧、熄灭）；说明：甲瓶里缺少______气，它是被萌发的种子______了．结论：萌发种子分解有机物时需要吸收______．（4）小结：通过这四个演示实验，你认为种子在萌发的时候有什么现象发生？ 1，______，2，______，3，______．
10 文字的演变经历了一个漫长和复杂的过程,它的最初形态是（） A 象形字符 B 图形契刻符号 C 表意字符 D 表音字符

已知有耳垂（Ｄ）对无耳垂（ｄ）是显性。某同学无耳垂，但他的父母都有耳垂，则该同学父母的基因型分别是（ ） A.Dd，Dd B.DD,DD C.DD,Dd D. Dd,DD

可能感兴趣的题目：

已知有耳垂（Ｄ）对无耳垂（ｄ）是显性。某同学无耳垂，但他的父母都有耳垂，则该同学父母的基因型分别是（）
A.Dd，Dd B.DD,DD C.DD,Dd D. Dd,DD