书城教材教辅科学读本(英文原版)(套装1-6册)
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第303章 第三册(128)

"This is why there is never very much carbonic acid gas in the air. As quickly as it is formed by breathing and burning, it is taken in by plants as their food."SUMMARY

The breathing of animals and burning of all sorts are constantly loading the air with carbonic acid gas. Plants breathe in this carbonic acid through the breathing pores of their leaves. It is part of their food.

Lesson 45

Life History of an Insect

"Look at that beautiful butterfly, Norah," said Fred. "Its life has been a strange one. If you will shut your eyes, and listen again as you did to the frog, you shall hear its history.

""I was once an ugly caterpillar." This is what it would say if it could speak. "I remember the time when I first crawled out from an egg. I was a verysmall, ugly, crawling thing then. My mother had laid the eggs for me and my brothers and sisters in the leaf of a cabbage. She put them there because she knew that we youngsters would be very fond of cabbage. That"s about the only kind thing she ever did for us, for she died soon after.