问题 读图填空题

下图为某遗传系谱图,系谱图中有患甲病(基因D、d)、乙病(基因B、b)和甲乙两病兼患者。Ⅱ2无乙病家族史。请回答以下问题(概率用分数表示)。

(1)乙病的遗传方式为________染色体________性遗传病。

(2)由于Ⅲ3个体表现两种遗传病,其兄弟Ⅲ2在结婚前找专家进行遗传咨询。专家的答复是:女性人群中甲、乙两种遗传病出现的概率分别为1/10000和1/100;如果婚后生下的是男孩则表现甲、乙两种遗传病的概率分别是_________、_________。

(3)若对Ⅰ1、Ⅰ2、Ⅱ1、Ⅱ2进行关于甲病的基因检测,将含有患病基因或正常基因的相关DNA片段(数宁代表长度)进行分离,结果如下图。(A、B、C、D代表上述个体)请回答:

①.基因检测的原理是_____________。

②.长度为________单位的DNA片段含有患病基因。

③.个体D是系谱图中的________号个体。

答案

(1)X  隐

(2)1/303   1/11

(3)①.DNA分子杂交  ②.7.0  ③.Ⅱ1

阅读理解

The Baima is a minority group of about 1,400 people. They have lived in Northern Sichuan and Southern Gansu Provinces for centuries. They have long depended on the forests as their main source of income. But since a ban on cutting down forests was introduced in the late 1990s to fight yearly flooding, the villagers have had to look for other means of earning a living.

Several are now in the process of developing a small tourism industry as their lands are rich in forests and natural scenery and are the home of the giant pandas. Xiangshujia, in particular, is becoming a popular bed and breakfast centre for tourists heading to Wanglang to see the giant pandas. Visitors are also starting to take notice of the Baima people themselves.

As our jeep stopped in the courtyard of a house, we were greeted by the village leader Li Qin and young Baima girls dressed in traditional costumes with white feathers in their hair. As we took our places on wooden benches near an open fire, the girls began to sing traditional songs as they served us.

“The number of tourists is growing,” said Li Qin. “We realize that to attract visitors we have to show our culture by offering more traditional singing and dancing and ensuring our houses are built in the traditional way.”

Relations between the Baima people and the reserve were once tense following the ban on cutting down forests. Villagers had to make a new living. They entered the Wanglang Nature Reserve to collect wild mushrooms and herbs (药草), often at the expense of disturbing the pandas’ habitat. But things greatly improved as villagers started receiving training in how to sell things to tourists.

“Our aim was to deter the villagers, because they often disturbed the pandas’ habitat, and to ensure they could have a long-lasting means of earning a living,” emphasized Chen Youping, director of the Wanglang Nature Reserve. “All the money from the reserve goes back into the community and conservation projects,” said Chen. “We take into consideration first the animals and then tourism.”

小题1:From Paragraph 1 we learn that ________.

A.the Baima has the longest history among all the minority groups in China

B.the Baima people live in most areas of Sichuan and Gansu Provinces

C.forests are the main source of firewood for the Baima people

D.in order to fight floods, the Baima people are forbidden to cut down forests小题2: We can infer that the Baima girls wore their traditional costumes to greet visitors mainly because _______.

A.they wanted to look more beautiful

B.their leader Li Qin asked them to do so

C.it was a way to show their culture to attract visitors

D.it was necessary before they sang traditional songs小题3:Which of the following was NOT an effect of the ban on cutting down forests?

A.The Baima people had a tense relationship with the reserve.

B.Villagers had to look for other means of making a living.

C.The pandas’ habitat was often disturbed by villagers.

D.Villagers stopped selling things to tourists.小题4:The underlined word “deter” in the last paragraph can be replaced by “________”.

A.punish

B.stop

C.encourage

D.threaten

单项选择题