问题
选择题
1997年,英国的“克隆羊”备受世界关注。“克隆羊”的关键之一是找到特殊的酶,这些酶能激活普通体细胞使之像生殖细胞一样发育成个体。有关酶的说法中错误的是 [ ]
A.高温或重金属能降低酶的活性
B.由题可知酶具有选择性和专一性
C.酶是具有催化作用的蛋白质
D.酶只有在强酸、强碱条件下才能发挥作用
答案
答案:D
1997年,英国的“克隆羊”备受世界关注。“克隆羊”的关键之一是找到特殊的酶,这些酶能激活普通体细胞使之像生殖细胞一样发育成个体。有关酶的说法中错误的是 [ ]
A.高温或重金属能降低酶的活性
B.由题可知酶具有选择性和专一性
C.酶是具有催化作用的蛋白质
D.酶只有在强酸、强碱条件下才能发挥作用
答案:D
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When I was in middle school, I was one of the smaller players on the basketball team. In our first game of the season, we were 1 to face a good team, all of whom were tall guys. Naturally, at my 2 , it would have been easy to be 3 by our competitors. On game day, my basketball coach called me over to him. He was a strong and tough coach, and in his 4 rough manner said, "Joel, you're not that 5 , but let me tell you that size doesn't matter. Don't be afraid. What 6 is right down in here." He pointed his finger at his 7 as he continued, "Joel, you've got a big heart, and you're to 8 it this year." When I heard the coach's 9 , I stood taller than usual! I thought to myself: The coach believes in me! My confidence 10 and I played better that year than I'd ever done before. It's 11 what we can achieve when we know somebody really believes in us. That coach took a little time to make a big 12 . He took time to make me confident in myself. If we're going to 13 the best in people, we need to sow seeds of 14 . As the saying goes, "Love looks for a way of being constructive." 15 , love looks for ways to help improve somebody else's life. When people are 16 us, they should leave better off than they were before. People should feel 17 and inspired after spending any time with you and me 18 feeling discouraged or defeated. Remember, there's 19 greater investment (投资) in life than in being a people builder. Relationships 20 much more to us than our achievements. | ||||
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