蛋白质属_____________，在碱性溶液中带______，在酸性溶液中带______。
参考答案：两性电解质、 负电 、正电
— What did Kincaid say just now?
— He said he ________ a dog if he hadn't been away from home too much. [ ]
A. had had
B. had
C. would have
D. would have had
蛋白质三级结构关键的化学键是（）
A.氢键
B.肽键
C.二硫键
D.范德华力
E.次级键
