教甄◆英文科題庫下載題庫

Can plants hear? Michael Marshall claims in New Scientist that plants might hear sounds. He mentions that Monica Gagliano led a team to conduct some experiments about how chilli peppers sensed neighboring plants even if those neighbors were sealed in a box. They placed some seeds of chilli peppers into eight Petri dishes (11) a potted sweet fennel plant, one kind of plant which releases chemicals into the air and soil that slow other plants’ growth. This team also prepared some experimental setups  (12) the fennel was enclosed in a box and thus its chemicals would be blocked from reaching the seeds. Other experiments had the box, but no fennel plant inside. In each case, the entire setup was sealed in a soundproof box to prevent outside signals from (13) . 

As expected, chilli seeds exposed to the fennel sprouted more slowly than when there was no fennel. Surprisingly, when the fennel was present but sealed up, those seeds sprouted fastest of all. Gagliano repeated the experiment with 2400 chilli seeds in 15 boxes and consistently got the same result, suggesting the seeds (14) responding to a signal of some sort. She believes that this signal makes the chilli seeds sense the (15) of chemicals that will slow their growth. Therefore, they undergo a growth spurt. Because the box surrounding the fennel would have blocked chemical signals, Gagliano suggests that sound may be involved.