下列关于酶辅基的叙述，正确是
A．是一种小肽，与酶蛋白结合紧密
B．只决定酶的专一性，与化学基团传递无关
C．一般不能用透析的方法与酶蛋白分开
D．是酶蛋白的某肽链C末端的几个氨基酸
参考答案：C
解析：酶的辅助因子按其与酶蛋白结合的紧密程度及作用特点不同分为辅酶及辅基。辅酶与酶蛋白结合疏松，可以用透析或超滤的方法除去。辅基与酶蛋白结合紧密，不能用透析或超滤的方法除去(C对)。在反应中辅基不能离开酶蛋白，一般对热稳定。金属离子多为酶的辅基，小分子有机化合物有的属于辅酶，有的属于辅基。
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| One day, an old friend of mine asked me, "What __1__ you do if you went to a __2__country and have serious culture shock?" I thought for a while. The following was my opinion. Every country has its unique culture. This is __3__ different countries have different races of people, are situated in different geographical locations and have different religions. This all contributes to the countries' own culture. Yet because the cultures are so different __4__ each other, there are times when foreigners are not accustomed to the culture and customs of the courty they're __5__, Some people might even find the culture totally unacceptable. If I was going overseas, I wouldmake sure to do some __6__ about the country I was visiting, and learn a bit about its __7__, just so I know what to expect of for any reason I was not prepared and got a huge __8__ after the arriving in the country, these are some of the things I could do. I could try __9__ the history and reason __10__ this strange culture, and try to respect and accept it. By doing this I am standing from the local people spoint of view, there fore it will be easier to accept their strange ways. | |||
| ( ) 1. A. would ( ) 2. A. beautiful ( ) 3. A. that ( ) 4. A. from ( ) 5. A. annoying ( ) 6. A. shopping ( ) 7. A. story ( ) 8. A. shock ( ) 9. A. to find ( ) 10. A. beliind | B. could B. large B. because B. with B. moving B. things B. duty B. c:hallenge B. finding B. in | C. should C. great C. though C. between C. visiting C. research C. influence C. realization C. to understand C. under | D. might D. strange D. when D. to D. looking for D. experience D. culture D. matter D. understanding D. over |