将等量且足量的苹果肉分别放在O2浓度不同的密闭容器中，1小时后，测定O2的吸收量和CO2的释放量如下表。下列有关叙述正确的是
A．苹果果肉细胞在O2浓度为0-3%和5%-25%时，分别进行无氧呼吸和有氧呼吸
B．苹果果肉细胞进行无氧呼吸时，产生乳酸和二氧化碳
C．O2浓度越高，苹果果肉细胞有氧呼吸越旺盛，产生ATP越多
D．贮藏苹果时，应选择O2浓度为5%的适宜环境条件
答案：D
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| "This Friday we'll have the yearly Egg Drop Challenge," said our science teacher, Mr. baker. "You can work alone or with a partner." My friend, Cassie, and I smiled at each other. We always worked on projets 1 . The 2 of the challenge was simple-to build a protective container to keep an egg from breaking when 3 the stadium wall. I made my sandwich that afternoon while waiting for Cassie. 4 the butter-cream gave me an idea. "I have a brilliant design for our 5 container!"I said when Cassie arrived."We can 6 the egg with some butter-cream." "Why not pit the egg in a basket with a parachute (降落伞) 7 ?" Cassie rolled her eyes. "The parachute is better than that stupid idea." I couldn't believe it, Of course we'd had our little 8 in the past, but she'd never called any of my ideas" 9 " before. "Then I'll build mine and you build yours!" 10 words had been out, our friendship was challenged. When Friday finally arrived, I had to 11 Cassie's Egg Force One looked pretty good. 12 , my Egg-cellent Egg Cream didn't look quite scientific. We kids carried our containers up three stadium steps and dropped them over the side wall. Those whose eggs broke were out; those whose eggs survived 13 three more steps and dropped them again. This would go on till the last egg broke. After four rounds, only Cassie and I were 14 . I let go of my box. I heard someone say"ew" after seconds. Had my egg broken? I raced down the 15 . The side walk was dotted with egg shells (蛋壳) from those 16 drops. Finally I found my little Egg-cellent Egg Cream. "That looks like egg drop soup, Laura,"Cassie said. She was holding her Egg Force One. My 17 raced. Had she won? I looked at her basket. 18 . "My egg bounced 19 ,"she explained, pointing to a broken shell. "A tie (平局),"Mr. Baker said. Cassie looked at me, and her glare 20 . I laughed. She smiled… | ||||
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