晴朗的夏天，在一株树的相同位置早晨和傍晚各取大小相同的叶片甲和乙，将两叶片脱水后称重，其质量关系是（ ）
A．甲=乙
B．甲＜乙
C．甲＞乙
D．无法确定
绿色植物的光合作用只在白天进行，呼吸作用时时刻刻都在进行，白天光合作用强度大于呼吸作用．早晨摘取叶片甲经过一晚上的植物呼吸作用，分解的有机物最多，光合作用的时间最短，积累的有机物最少，其重量最轻；傍晚摘取叶片乙经过一天的植物光合作用，时间最长，积累的有机物最多，其重量最重．植物积累的有机物等于光合作用制造的有机物减去呼吸作用消耗的有机物．
故选：B
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| Charlie Chaplin was the first international star of the modern art of movies. He was especially beloved for his Little Tramp 1 . He was the first screen artist to write, 2 and perform in his own films; in fact, in some cases, Charlie Chaplin even wrote the music for his movies. He was also the first artist to use his work to pass a 3 of equality and justice ( 正义) for all - 4 for the"little guy". Charlie Chaplin's career and life made 5 the first global icon (偶像); his too-small hat, his too large shoes and his trademark moustache were instantly recognized by audiences from Chicago to China, from Iowa City to India. And they 6 are today. All of these make Charlie Chaplin the first citizen of our global village. Chaplin, a native of London, was born in 7 on April 16, 1889 to music hall performers. Chaplin only saw his 8 twice until the age of seven. The man 9 him and his mother about a year after Chaplin was 10 . During Chaplin's earliest years, his mother was a(n) 11 and performer. Then her voice gave out, her stage career 12 , and she began actively attending Church of England services. At the age of 13 , Chaplin's mother was considered as the insane and sent to Cane Hill lunatic asylum (疯人院), and the court sent Charlie and his brother to live with his father, 14 had by then stopped all payments of child support. Charlie Chaplin lived with his father only a short time 15 his mother was released from the lunatic asylum and then picked up Charlie and his brother, to live with her once again. | ||||
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