问题 单项选择题 A1/A2型题

能引起促胰液素释放的最强物质是()。

A.葡萄糖

B.盐酸

C.碳酸氢盐

D.脂肪分解产物

E.蛋白质分解产物

答案

参考答案:B

解析:产生促胰液素的细胞为S细胞。王志均等曾在具有移植胰的狗身上观察引起促胰液素释放的因素,结果表明,盐酸是最强的刺激因素,其次为蛋白质分解产物和脂酸钠,糖类几乎没有作用。小肠内促胰液素释放的pH为4.5。迷走神经的兴奋不引起促胰液素的释放;切除小肠的外来神经,盐酸在小肠内仍能引起胰液分泌,说明促胰液素的释放不依赖于肠管外来神经。

阅读理解

“Sesame Street” has been called “the longest street in the world”. That is because the television program by that name can now be seen in so many parts of the world. That program became one of American’s exports soon after it went on the air in New York in 1969.

In the United States more than six million children watch the program regularly. The viewers include more than half the nation’s pre-school children, from every kind of economic(经济的), racial(种族的), and geographical group.

Although some educators object to certain elements in the program, parents praise it highly. Many teachers also consider it a great help, though some teachers find that problems arise when first graders who have learned from “Sesame Street” are in the same class with children who have not watched the program.

Tests have shown that children from all racial, geographical, and economic backgrounds have benefited from watching it. Those who watch it five times a week learn more than occasional(偶然的) viewers. In the US the program is shown at different hours during the week in order to increase the number of children who can watch it regularly.

The programs all use songs, stories, jokes, and pictures to give children a basic understanding of numbers, letters and human relationships. But there are some differences. For example, the Spanish program, produced in Mexico City, devotes more time to teaching whole words than to teaching separate letters.

Why has “Sesame Street” been so much more successful than other children’s shows? Many reasons have been suggested. People mention the educational theories(理论) of its creators, the support by the government and private(私人的) businesses, and the skillful use of a variety of TV tricks. Perhaps an equally important reason is that mothers watch it along with their children. This is partly because famous adult stars often appear on it. But the best reason for the success of the program may be that it makes every child watching feel able to learn. The child finds himself learning, and he wants to learn more.

小题1:“Sesame Street” is actually _______.

A.a street in the US

B.a program for children

C.a program for teachers

D.a program for students小题2:Children who often watch the program _______.

A.can have problems in school

B.will find it a great help

C.will take no interest in their studies

D.will be well educated小题3: What is special about the program?

A.It offers great fun.

B.It makes children feel able to learn.

C.It is shown at different hours during the week.

D.Children learn and enjoy themselves while watching.小题4: Why is “Sesame Street” so popular in the world?

A.Because it is supported by the government and businesses.

B.Because it uses a variety of skillful tricks.

C.Because mothers watch it along with their children.

D.Because it makes every child watching it feel able to learn.小题5:The best title for this passage can be _______.

A.TV Programs

B.Educating Children

C.Sesame Street

D.A Great Success

多项选择题