6.有一种软骨发育不全的遗传病，两个有这种病的人结婚，生了一个患软骨发育不全的孩子，而他们的第二个孩子却是正常的，他们再生一个孩子患此病的几率是

A.100%　　　　　　　　　　　　　　　 B.75%　　　　　　　　　　　　　　　　 C.25%　　　　　　　　　　　　　　　　 D.50%

5.要判断某一个体是不是纯合体，最好的方法是

A.让其与杂合体交配　　　　　　　 　　　　　　　　　　　　　　　　　　 B.让其与纯合体交配

C.让其与隐性类型交配　　　　　　　　　　　　　　　　　　　　　　　 D.让其与显性类型交配

4.桃果实表面光滑对有毛为显性。现对毛桃的雌蕊授以纯合光桃的花粉，该雌蕊发育成的果实应为

A.光桃　　　　　　　 B.毛桃　　　 C.光桃的概率为　　　　　　　　　 D.毛桃的概率为

3.一株纯种黄粒玉米与一株纯种白粒玉米相互授粉，比较这两个植株结出的种子中胚和胚乳的基因型，其结果是

A.胚的基因型不同，胚乳的基因型相同　　 B.胚的基因型相同，胚乳的基因型不同

C.胚和胚乳的基因型都相同　　　　　　　 D.胚和胚乳的基因型都不同

2.我国婚姻法规定禁止近亲婚配的医学依据是

A.近亲婚配其后代必患遗传病　　　　 B.近亲婚配其后代患隐性遗传病的机会增多

C.人类的疾病都是由隐性基因控制的　 D.近亲婚配其后代必然有伴性遗传病

1.关于杂合体的叙述不正确的是

A.至少有一对等位基因　　　　　　　　 B.自交后代有性状分离

C.自交后代仍是杂合体　　　　　　　　 D.能产生多种类型的配子

B

It’s ten to six in the afternoon. Li Kai comes back from school. His mother is not at home and the door is locked (锁着). His brother, Li Qiang, is playing football in the school. He likes sports very much and always plays after school. His sister, Li Jun, likes music. She has to join a music lesson at six every day. Li Kai can’t get into the house, so he brings out a marble(弹珠) and plays near the house.

After about fifteen minutes, Li Kai’s mother comes back with a bag. Li Kai sees her and runs to her. He helps his mother put the bag into the kitchen. Li Kai finds three cakes in the bag. They are his favourite food and he wants to eat.

“The other two are for Li Qiang and Li Jun,” says his mother. “You each have one.”

“But can I have two, Mum?” says the boy.

“Yes, you can. Go and cut yours in half!”

51. Li Kai gets home at _____.

A. 5:10　 　　　　 　　　　　　　 B. 6:10 　　　 　　　　　　　 C. 5:00　 　　 　　　　　　　 D. 5:50

52. Li Kai can not get into his house______________.

　 A. because he comes home early

　 B. because his mother is at home

　 C. because his mother goes out to do some shopping and the door is locked

　 D. because his sister, Li Jun, is playing football

53. How many children does Mr Li have?

　 A. One.　 　　　　　　　　　　 B. Two.　　 　　　　　　　 C. Three.　　 　　　　　　　 D. Four.

2009/2010学年度第二学期七年级英语期末试卷答题卷

(满分100分)

A

The Turners are Americans．They are now in Beijing．

　 This is their first visit to China．They are going to stay in China for three months．They want to visit some big cities and villages．They hope to learn some Chinese，too．Mr Turner is a driver．He likes to drive in Beijing．Mrs Turner is a school teacher．She is visiting a city school and a village school．Their daughter is a middle school student．She meets some Chinese students．They take a lot of pictures in China．When they are back in America，they are going to show the pictures to their friends．They want the American people to know more about China．

46．The Turners are from _____ .

　　 A．America　　 　　　　　 B．England　　 　　　　　 C．China　　　　　　　 D. Africa

47．The Turners are staying in _____ now．

　　 A．Shanghai　　 　　　　 B．Beijing　　 　　　　　　 C．London　　　　　　 D. their hometown

48．Mrs Turner’s _____ is a middle school student．

　　 A．son　　 　　　　　　　　 B．sister　　 　　　　　　　 C．daughter　　　　　 D. friend

49．There are _____ people in Mr Turner’s family．

　　 A．two　　 　　　　　　　　 B．three　　 　　　　　　　 C．four　　　　　　　　 D. five

50．They take a lot of pictures in China because _____ .

A. they like to take pictures 　　　　　　　　　　　

B. they love China

　 　C. they want to have a picture show in Beijing

　　 D. they want the American people to know more about China