DNA的二级结构稳定因素主要是碱基之间的氢键和碱基对平面之间的堆积力维持。
A. 对
B. 错
tRNA三级结构是三叶草形结构
A. 对
B. 错
process
A. frequently or habitually
B. a series of actions/steps taken to achieve something
C. difficult to deal with, intimidating
strategy
A. a plan of action
B. a promise or assurance that something will happen
C. the act of trying hard
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