问题 单项选择题 A1/A2型题

口腔细菌种类复杂的主要原因是()

A.口腔内温度保持在36~37℃

B.口腔内pH比较稳定,平均为6.7~7.2

C.口腔内营养充足

D.口腔内不同部位有不同的氧化还原电势

E.细菌对牙面有黏附、相互协同及拮抗作用

答案

参考答案:D

解析:口腔内细菌种类复杂的主要原因,是由于不同部位有不同的氧化还原电势,适宜多种需氧、兼性厌氧和专性厌氧细菌的生长,而温度、pH及营养等因素是口腔内适合绝大多数微生物生长的原因,因此答案应选D。

阅读理解

Once there was a king who never ate a meal unless there was a dish of fish with it, but one day there was a big storm and the fishermen were not able to go out to catch fish, so the king had no breakfast and no lunch. Then he ordered his servants to tell everybody in his capital that if anyone brought him a fish, he would give him anything that he asked for.

At last, a fisherman caught a big fish late in the afternoon and hurried to the king's palace with it. But the king's Prime Minister would not let him in until he promised to give him half of whatever the king gave him for the fish.

The king was very happy when he saw the fish. He asked the fisherman what he wanted for his fish. To his surprise, the fisherman said, "I want you to beat me two dozen(一打) times with a stick." When the king began to beat him a dozen times, the fisherman jumped away and said, "That is enough for me. I promised the other dozen to your Prime Minister." Then he told the king what had happened between the Prime Minister and himself. The king was very angry. He not only gave the Prime Minister the dozen hits, but also said, "Because you have been dishonest, you will not be my Prime Minister any more. The fisherman will take your place."

小题1:The king didn't have breakfast and lunch because ____.

A.there was a big storm

B.the Prime Minister did not bring him any food

C.there was no fish

D.his servants didn't know how to cook well小题2:. The fisherman took his fish to the king's palace because ____.

A.the king had promised to give him whatever he wanted

B.the king was dying from hunger

C.he wanted to teach the Prime Minister a lesson

D.he wanted to be the Prime Minister小题3:. When the fisherman told the king what he wanted, the king ____.

A.was very happy

B.was very surprised

C.was very angry

D.gave him what he wanted at once小题4:. The king got rid of his Prime Minister because ____.

A.the fisherman was cleverer than his Prime Minister

B.the Prime Minister did not know how to catch fish

C.the Prime Minister was not an honest man

D.the Prime Minister took half of what the king gave the fisherman

多项选择题