【正确答案】 C

【答案解析】[听力原文]31-34
　　There are many kinds of nerve cells, and this chapter deals mainly with three kinds. Tire sensory nerve cells carry messages of heat, light, sound and pressure from the skin, muscles and organs inside the body. Motor nerve cells carry messages to the muscles, and this causes the muscles to move. Connecting nerve cells go between the sensory nerve cells and motor nerve cells. After the messages go from the spinal cord to the brain, the brain sends messages through the motor nerve cells to the muscles. All these different nerve cells help us to see, hear, taste, smell and feel.
Now if you have no further questions about chapter seven, we'll go on to talk about the chemical processes involving the transfer of messages.
31. How many kinds of nerve cells are mentioned in this passage?
[试题分析]本题考查考生对数字细节的掌握。
[关键词句]and this chapter deals with three kinds
[详细解答]第一句即告诉我们“本章讲解三种神经细胞”，故选C。

【正确答案】 B

【答案解析】[听力原文]
What is one function of sensory nerve cells?
[试题分析]本题考查考生对细节的掌握。
[关键词句]carry messages
[详细解答]感觉神经细胞的功能是传送信息，故选B。

【正确答案】 A

【答案解析】[听力原文]
What is the source of the speaker's information?
[试题分析]本题考查考生的判断推理能力。
[关键词句]chapter，questions
[详细解答]讲话者在该篇开头、结尾都提到了"chapter"一词，并询问大家是否有问题，因而可以判断出，他是位教师，故本题答案为A。

【正确答案】 B

【答案解析】[听力原文]
What is the main idea of this passage?
[试题分析]本题考查考生对全篇中心内容的把握。
[关键词句]nerve cells，3 kinds
[详细解答]听懂第一句往往是关键。本文介绍了三种神经细胞及其功能，故选B。