问题 选择题

乙酰胆碱的主要功能是从神经细胞携带信号到肌肉。一旦信号通过,立即发生乙酰胆碱胆乙酸+胆碱。分解后的胆碱在Na+协同下运入细胞重新合成乙酰胆碱,关于该反应的叙述不正确的是[ ]

A.防止递质长时间起作用   

B.该酶是生物体内催化效率较低的酶之一   

C.胆碱被运入细胞可再次利用   

D.神经毒气与该酶结合可扰乱心肌信息传递

答案

答案:B

阅读理解

Mr. Brown was going away for a week. Before he left, he said to his son, "if anyone asks for me, you can tell him that your father has been out for doing something, and will be back in a week, then be sure to ask him to sit down for a cup of tea."

"OK, Dad," said his son. But he was afraid his son couldn’t remember this, he wrote these words down on a piece of paper and gave it to him. His son put it into his small pocket, took it out and looked at it every now and then.

Four days passed, but no one came to see his father. The boy thought that there was no man to come and that the piece of paper was of no more use for him, so he burnt it that evening.

The next afternoon, someone knocked at the door. The boy opened it. A man was standing at the door and said, "Where is your father?" The boy put his hand into his pocket at once and looked for the piece of paper. He could not find it. He suddenly remembered he had burnt it, so he shouted, "No more."

The man was very surprised. He asked, "No more? I met your father last week. When did it happen?" "Burnt yesterday evening."

小题1:Mr. Brown told his son that _____.

A.he would be away from home for four days

B.he would be back in seven days

C.he would be back in a month

D.he liked a cup of tea小题2: Mr. Brown wrote the words down on ________.

A.the wall

B.the door

C.a piece of paper

D.his son’s pocket小题3:A man came to visit the boy’s father on ________.

A.the second day

B.the third day

C.the fourth day

D.the fifth day小题4:The man was very surprised because _________.

A.he thought the child’s father was dead

B.the child didn’t ask him to sit down

C.the child gave him a cup of tea

D.he couldn’t find that piece of paper小题5:What was burnt? ___________.

A.The piece of paper.

B.Mr. Smith.

C.The visitor.

D.The boy.

单项选择题