问题 选择题

用含某种激素的饲料喂蝌蚪,能缩短蝌蚪发育成蛙的时间,这种激素是(  )

A.性激素

B.生长激素

C.肾上腺皮质激素

D.甲状腺激素

答案

甲状腺激素是由甲状腺分泌的,它的主要作用是促进新陈代谢、促进生长发育、提高神经系统的兴奋性;用含某种激素的饲料喂蝌蚪,能缩短蝌蚪发育成蛙的时间,说明该激素能够促进蝌蚪的生长发育,因此这种激素应该是甲状腺激素;性激素的作用是促进性器官的发育和促使第二性征的出现、维持人体的第二性征;生长激素是由垂体分泌的,有调节人体生长发育的作用;肾上腺皮质激素的作用是调节动人体内的水盐代谢和糖代谢.

故选:D

阅读理解

After twenty years of shaving(剃须)himself every morning, a man in a small Southern town thought he had enough. He told his wife that he intended to let the local barber shave him each day. He put on his hat and coat and went to the barber shop.

The barber's wife, Grace, was working that day, so she performed the task. Grace shaved him, and said, "That will be $20." The man thought the price was a bit high, but he paid the bill and went to work.

The next morning the man looked in the mirror, and his face was as smooth as it had been when he left the barber shop the day before. “Not bad, he thought. At least I don't need to get a shave every day.”

The next morning, the man's face was still smooth. Two weeks later, the man was still unable to find any trace of whiskers on his face. It was more than he could take and he was frightened, so he returned to the barber shop.

"I thought $20 was high for a shave", he told the barber's wife, "but you must have done a great job. It's been two weeks and my whiskers still haven't started growing back." The expression on her face didn't even change, expecting his comment. She responded, "You were shaved by Grace and once shaved, always shaved!"

小题1:It’s implied in the first sentence of the passage that          .

A.the man lived a very poor life

B.the man liked shaving himself

C.the man finally got bored of shaving himself

D.the man decided not to shave again小题2:We learn that at first the man thought $20 for a shave was         .

A.too little

B.too much

C.proper

D.impossible小题3:What can we learn from the passage?

A.Everybody in the town knows Grace.

B.Nobody wants to be shaved by Grace in the town.

C.The man was scared by the result two weeks later.

D.The man’s whiskers grew back at last.

问答题