问题 读图填空题

下表是“比较过氧化氢在不同条件下的分解”实验设计相关内容,下图为在最适温度下反应物浓度对酶促反应速率的影响。请据此分析回答:

(1)请填出4号试管的实验现象____________。

(2)比较1号和2号试管,你得出的结论是_______。比较3号和4号试管,你得出的结论是___________ 。

(3)下图为4号试管中反应物浓度与反应速率关系图,对于BC段而言,反应速率不发生变化的原因是______________。

答案

(1)大量气泡,带火星的卫生香猛烈复燃

(2)加热加热提高过氧化氢分解速率      过氧化氢酶的催化效率远高于Fe3+

(3)过氧化氢酶含量一定

选择题
阅读理解

The art of public speaking began in ancient Greece over 2,000 years ago. Now, twitter, e-mail, blogs and QQ chat offer approaches to communication— but none can replace the role of a great speech.

The spoken word can handle various important functions: persuading or inspiring, informing, paying tribute (致敬), entertaining, or simply introducing someone.

Persuading is used in dealing with or reconciling different points of view. When the leaders met in Copenhagen in December, 2009, persuasive words from activities encouraged them to take former action.

Inspirational speeches deal with emotions. They focus on topics and matters that are close to people’ s hearts. Last year, during the fighting in Iraq, generals used inspiring speeches to prepare the troops for battle.

Some speeches spread knowledge and deepen understanding. When the H1N1 flu was announced, the disease scared many people. Informtive speechs from World Health Organization (WTO) officials helped people to keep their panic under control so they could take necessary preventive measures.

Sad events are never easy to deal with but a speech that pays tribute to the loss of a loved one and gives praise for their contribution can be comforting. Madonna’s speech about Michael Jackson after his death showed the fact that he will continue to live on through his music.

It’s not only in world forums where public speaking plays an important role. It can also be helpful in the course of our own life. You may be asked to do a presentation at college or work to inform others about an area of great importance. On a more personal level, a friend may be upset and need comforting. Or you might be asked to introduce a speaker at a family gathering or to speak at a wedding, where your language will be needed to move people or make them laugh.

Great speaking ability is not something we’re born with. Even Barack Obama works hard to perfect every speech.

小题1:The underlined word “recociling” in paragraph 3 can best be replaced by “________”

A.considering

B.questioning

C.accepting

D.settling小题2:The passage mentions the H1N1 flu to show the function of _______

A.persuasive speeches

B.informative speeches

C.inspirational speeches

D.introductive speech小题3:The 7th paragraph mainly tells us that public speaking ______.

A.is important in world forums

B.can help us make more friends

C.matters more in one’s life

D.is helpful in our daily life小题4:What would the writer probably talk about following the last paragraph?

A.How the speech came into being

B.Why the public speaking is imporatant.

C.How you can perfect your speech

D.Why Obama often makes speeches小题5:What would be the best title for the passage?

A.Tips of great speeches

B.The history of the speech

C.Functions of the speech

D.The language of the speech