问题 单项选择题

关于血浆中[H]、[HCO]与[Ca]之间的关系叙述正确的是()

A.[H]增高,[Ca]下降

B.[H]增高,[Ca]增高

C.[HCO]增高,[Ca]增高

D.[HCO]下降,[Ca]下降

E.[H]下降,[Ca]增高

答案

参考答案:B

解析:

血浆中存在下列反应:

①Ca+CO→CaCO

②CO+H→HCO

③HCO+H→HCO

并且以上三个均为可逆反应。

当[H]增高的时候,反应②主要向右进行,导致[CO]降低,从而使反应①得以向左边进行,[Ca]增高。

阅读理解

阅读理解。

     Have you ever seen the Statue of Liberty? It is a tall figure of a robed (披长袍的) woman holding a

torch (火把). She stands proudly on Liberty Island in New York Harbor. The statue is a symbol of freedom

for the United States. It was given as a gift to the United States by France in 1884. The statue is one of the

largest ever built, It stands 151 feet high from its base to the top of the torch. When the statue was shipped

to America, it could not be sent in one piece. Instead it was taken apart and packed in 214 separate (分离的)

crates (板条箱).

1. What is the Statue of Liberty? 

                                                                                                         

2. Who gave the statue to the United States? 

                                                                                                         

3. How tall is the statue?

                                                                                                         

4. How was it sent to America? 

                                                                                                         

5. Was it sent in one piece?

                                                                                                         

单项选择题