下列关于基因表达的概念叙述哪项正确?() ["其产物不包括RNA","其产物总是蛋白质","其产物可以是RNA或蛋白质","其产物总是RNA","其产物不包括蛋白质"]
Tc是()。 ["抑制性T细胞","辅助性T细胞","细胞毒性T细胞","免疫调节T细胞","抗原递呈T细胞"]
对于极微量的靶序列的扩增可以采用下列哪种PCR技术?() ["AP-PCR方法(arbitrarily primed PCR)","通用引物-PCR方法(general primer-mediated PCR,GP-PCR)","套式PCR(nested primers-polymerase chainreaction,NP-PCR)","多重PCR(multiplex PCR)","原位PCR技术(in situ PCR,ISPCR)"]
下列哪项可使原核生物转录过程终止?() ["全酶","ρ因子","σ因子","核心酶","α亚基"]
()的特征是鼻根低,鼻梁线条流畅但短,鼻孔可见度大。 ["A、蒜形鼻","B、鹰钩鼻","C、尖形鼻","D、翘鼻"]
()称为空串;()称为空白串。