问题
选择题
可以保护和支持蝗虫内部柔软器官,防止体内水分蒸发,使蝗虫更好地适应陆地生活的结构是( )
A.表膜
B.骨骼
C.肌肉层
D.外骨骼
答案
蝗虫的体表具有坚硬的外骨骼,其主要作用是保护和支持内部的柔软器官、防止体内水分的蒸发散失.这是适应陆地生活的特点之一.外骨骼不能随着蝗虫身体的生长而长大,所以在蝗虫的生长发育过程中,有脱掉原来的外骨骼的现象,这就是蜕皮.
故选:D
可以保护和支持蝗虫内部柔软器官,防止体内水分蒸发,使蝗虫更好地适应陆地生活的结构是( )
A.表膜
B.骨骼
C.肌肉层
D.外骨骼
蝗虫的体表具有坚硬的外骨骼,其主要作用是保护和支持内部的柔软器官、防止体内水分的蒸发散失.这是适应陆地生活的特点之一.外骨骼不能随着蝗虫身体的生长而长大,所以在蝗虫的生长发育过程中,有脱掉原来的外骨骼的现象,这就是蜕皮.
故选:D
One Sunday, a picture in the newspaper touched me. A young woman stood in front of a totally destroyed home. A little boy stood beside her with his head . Holding her skirt tightly was a tiny girl, eyes wide with and fear. With growing I noticed that their sizes of each family member closely ours. This would be a good opportunity to my children, so I explained their difficult to my seven-year-old twins and three-year-old Meghan. “We have so much, but these poor people now have nothing,” I said, “we’ll what we have with them.” I brought three large boxes and placed them on the living room floor. Meghan watched seriously the boys and I filled one box with canned food. While I our clothes, I encouraged the boys to go through their toys and some of their less favorite things. Meghan watched as the boys piled up useless toys in the box. “I’ll help you find something for the little girl,” I said to her. The boys placed the toys they had to donate into one of the boxes while I filled the third box with clothes. Meghan walked up with Lucy, her worn, faded, much-loved doll tightly to her chest. She in front of the box, pressed her little face into Lucy’s face, gave her a kiss, then, laid her gently on top of the other toys. “Oh, honey,” I said. “You to give away Lucy. You love her so much.” Meghan nodded, eyes shining with tears. “Lucy makes me happy, Mommy. she’ll make that little girl happy, too.” I stared at Meghan for a long moment, how I could teach the boys the lesson she had just taught me. It’s easy to give what we don’t want any more, but to let go of things we cherish, isn’ t it? , the true spirit of giving is to give with your heart.
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