书城教材教辅科学读本(英文原版)(套装1-6册)
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第300章 第三册(125)

"Teacher says insects have neither lungs nor gills," said Will. "They have instead two long canals in the body, which end in breathing holes, in the loose side skin, joining the upper and lower segments. These canals send out branching tubes into all parts of the body.

"The air which is taken in at the breathing holes on the sides of the body is carried into every cornerby these tubes, and so the blood all over the body is cleansed. The insect"s blood is cold and colorless."SUMMARY

Most insects have two pairs of wings-some have no wings. All have three pairs of legs. The legs and feet are made to suit the life of each kind of insect. Some are made for leaping, some for digging in the ground. The bee"s thighs form baskets. Insects have neither lungs nor gills. They breathe through slits in the loose, side skin.

Lesson 44

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