A
Do plants listen to music? How can a plant possibly respond to music? Well，plants breathe through their many mouths，which are also known as stomata and it has been discovered that plant stomata respond to music!
A few years ago，scientists at the University of California，San Diego discovered what controls a plant's stomata.The two cells that form the stoma consist of specialized cells adjusted to the resonant(共鸣的)frequency of calcium(钙)．When exposed to this frequency the stomata close.However，if the frequency isn't exactly right the cells will open again within an hour.This happens even if the concentration of calcium is high enough that the stomata would normally close.
When specific music or bird songs cause the plant to vibrate(颤动)，but not at the exact frequency for calcium resonance，the stomata will open after a misjudgment of time，even though the plant would keep them closed under normal circumstances.
Testing has shown that a leaf fertilizer(肥料)applied to the plant will have more effect on the development and growth of the plant if its stomata are wide open.This is quite logical，because plants absorb the leaf fertilizer through their stomata.Combinations of frequency and leaf fertilizer are available for many different crops.However，if the stomata are forced to remain open，the plant won't be able to control the amount of water lost and so it risks dehydration(脱水)．As a result，exposing plants to music for over 3 hours a day could endanger their health.There could also be bad effects on plants if the volume or frequency is too high.
It isn't exactly clear how music influences the development and growth of plants，but more and more is being discovered about resonance physics and we're closer than ever to solid scientific proof and theories in this area.Maybe，in twenty years' time people will laugh if you say plants don't have ears!
【语篇解读】 本文是一篇科普文。主要介绍了音乐对植物的影响。
1．Why does the author ask the questions in Paragraph 1?
A．To express his doubts.
B．To present different ideas.
C．To describe the lifestyle of plants.
D．To introduce points for discussion.
D [推理判断题。根据文章第一段中的“it has been discovered that plant stomata respond to music”以及下文内容可以推断，作者在文章首段提出那两个问题是为了引出本文要讨论的主题。]
2．What does the underlined word “This” in Paragraph 2 refer to?
A．The reopening of the cells.
B．The change in frequency.
C．The frequency of calcium.
D．The closing of the stomata.
A [代词指代题。根据上下文内容可知，画线词是指代上文提到的“the cells will open again”这一情况。]
3．It call be inferred from the text that .
A．future plants are likely to have ears
B．how music affects plant growth is widely known
C．growers must be careful when exposing plants to music
D．the stomata don't affect the effect of leaf fertilizer on plants
C [推理判断题。根据文章第四段内容可知，如果让植物长时间地暴露在音乐环境中或者音乐的音量或频率过高，会对植物产生不良的影响，如植物会脱水等。由此可以推断，种植者在让植物暴露在音乐环境中时必须小心。]
4．Which can be the best title for the text?
A．Benefits of Music to Plants
B．Influence of Music on Plants
C．How to Improve Plant Growth?
D．How Do Plants Listen Without Ears?
B [标题归纳题。通读全文可知，本文主要讲音乐能够促进植物的生长，但是如果让植物长时间地暴露在音乐环境中或者音乐的音量或频率过高，反而会对植物产生不良的影响。由此可知，B项“音乐对植物的影响”最能概括本文的内容。]
