两性生物碱
参考答案：生物碱分子中如有酚羟基和羧基等酸性基团，称为两性生物碱。
The lawyer didn't think this case was________.[ ]
A. of greatly significant
B. great significant
C. of great significance
D. great significance
论述生态系统稳定性及保证生态系统稳定需要的条件。
