题目

Men can be beautiful too, right?     CHINA is going to host the 18th World University Student Beauty Contest in Guangzhou this December. This year for the first time the contest will include a male section. Students from over 130 countries will compete for Mr. and Miss Beauty. The contest is one of the most respected beauty contests in the world. It was copied by the United Nations University (an international university belonging to the United Nations) in 1986.      Stick to studying      LI Yining, an economics professor at Peking University, said that he would not encourag酶的活性中心是指：A.酶分子上含有必需基团的肽段B.酶分子与底物结合的部位C.酶分子与辅酶结合的部位D.酶分子发挥催化作用的关键性结构区