问题 单项选择题 A1型题

酶能加速化学反应的进行,其原理是()

A.降低反应的活化能

B.降低反应的自由能变化

C.降低底物的能量水平

D.向反应体系提供能量

E.提高产量物的能量水平

答案

参考答案:A

解析:酶是由生物体内细胞产生的对其特异底物起高效催化作用的蛋白质(少数为RNA)。酶的催化作用实质为降低化学反应活化能,从而起到催化化学反应的作用,加快化学反应的速度,提高化学反应的效率。故选A。

阅读理解

Jacqueline Bouvier Kennedy Onassis was one of the most private women in the world, yet when she went to work as an editor in the last two decades of her life, she revealed (展现) herself as she did nowhere else.

After the death of her second husband, Greek shipping magnate(巨头) Aristotie Onassis Jacqueline’s close friend and former White House secretary Letitia Baldrige made a suggestion that she consider a career in publishing. After consideration, Jacqueline accepted it. Perhaps she hoped to find there some ideas about how to live her own life .She became not less but more interested in reading. For the last 20 years of her life, Jacqueline worked as a publisher’s editor, first at Viking, then at Doubleday, pursuing(追求)a late-life career longer than her two marriages combined. During her time in publishing, she was responsible for managing and editing more than 100 successfully marketed books. Among the first books were In the Russian Style and Inventive Paris Clothes. She also succeeded in persuading TV hosts Bill Moyers and Joseph Campbell to transform their popular television conversations into a book ,The Power of Myth. The book went on to become an international best-seller. She dealt, too, with Michael Jackson as he prepared his autobiography(自传),Moonwalk.

Jaequeliner may have been hired for her name and for her social relations, but she soon proved her worth. Her choices, suggestions and widespread social relations were of benefit both to the publishing firms and to Jacqueline herself. In the books she selected for publication, she built on a lifetime of spending time by herself as a reader and left a record of the growth of her mind. Her books are the autobiography she never wrote. Her role as First lady, in the end, was overshadowed by her performance as an editor. However, few knew that she had achieved so much.

小题1:We can learn from the passage that Jacqueline ______.

A.became fond of reading after working as an editor

B.was in charge of publishing 100 books

C.promoted her books through social relations

D.gained a lot from her career as an editor小题2:The underlined sentence in the last paragraph probably means that ______.

A.Jacqueline ended up as an editor rather than as First Lady

B.Jacqueline’s life as First Lady was more colorful than as an editor

C.Jacqueline was more successful as an editor than as First Lady

D.Jacqueline’s role as First Lady was more brilliant than as an editor小题3:What can be inferred from the passage?

A.Jacqueline’s two marriages lasted more than 20 years

B.Jacqueline’s own publishing firm was set up eventually

C.Jacqueline’s views and beliefs were reflected in the books she edited

D.Jacqueline’s achievements were widely known小题4:The passage is mainly ______.

A.an introduction of Jacqueline’s life both as First Lady and as an editor.

B.a brief description of Jacqueline’s lifelong experiences.

C.a brief account of Jacqueline’s career as an editor in her last 20 years.

D.an analysis of Jacqueline’s social relations in publishing

多项选择题